Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Default More about that Chinese amp

Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric
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On 31/12/2019 4:45 am, wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?

--
Trevor Wilson
www.rageaudio.com.au
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Default More about that Chinese amp

On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am, wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?

Because I like it. It sounds good. People spontaneously comment on
how good it sounds. Not how it sounds almost as good as a solid state
amp. And I like tubes.
Are you grumpy today?
Eric
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On Mon, 30 Dec 2019 12:11:47 -0600, Fox's Mercantile
wrote:

On 12/30/19 11:45 AM, wrote:
So, anybody have suggestions on tubes?


https://www.tubesandmore.com/products/el34b-valve-art

Thanks Jeff. I may order them today. Trevor at Rage Audio just raged
at me and told me to throw away my tube amp. I wonder if the heat Down
Under is getting to him?
Eric


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Default More about that Chinese amp

On 31/12/2019 5:50 am, wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?

Because I like it. It sounds good.


**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.


**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.


**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?


**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.


--
Trevor Wilson
www.rageaudio.com.au
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Default More about that Chinese amp

On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am, wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?

Because I like it. It sounds good.


**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.


**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.


**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?


**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.

On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric
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Default More about that Chinese amp

On 31/12/2019 9:34 am, wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.


**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.


**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.


**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?


**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.

On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.

--
Trevor Wilson
www.rageaudio.com.au
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On Monday, December 30, 2019 at 12:45:33 PM UTC-5, wrote:

So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric



The Russians make pretty good EL34s these days, but I prefer the old 6CA7s. I still have a small stash of those left.


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On 31/12/2019 10:02 am, John-Del wrote:
On Monday, December 30, 2019 at 12:45:33 PM UTC-5, wrote:

So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric



The Russians make pretty good EL34s these days, but I prefer the old 6CA7s. I still have a small stash of those left.


**Me too. I have a bunch of those steel, MIL-Spec ones.

--
Trevor Wilson
www.rageaudio.com.au
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On Monday, December 30, 2019 at 6:06:20 PM UTC-5, Trevor Wilson wrote:
On 31/12/2019 10:02 am, John-Del wrote:
On Monday, December 30, 2019 at 12:45:33 PM UTC-5, wrote:

So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric



The Russians make pretty good EL34s these days, but I prefer the old 6CA7s. I still have a small stash of those left.


**Me too. I have a bunch of those steel, MIL-Spec ones.

--
Trevor Wilson
www.rageaudio.com.au



Wow, never saw a 6CA7 metal tube. Learn something new every day. I also have a sleeve of NOS 8417s that I used in a Fisher for a customer many years ago.
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On Tuesday, December 31, 2019 at 8:06:59 AM UTC-5, John-Del wrote:

Wow, never saw a 6CA7 metal tube. Learn something new every day. I also have a sleeve of NOS 8417s that I used in a Fisher for a customer many years ago.


Metal tubes were common in military and aircraft radios, because they could withstand a lot more vibrations. One thing to watch is that some metal version can't dissipate the same power levels as the later glass versions. I used to run into so called repairs where someone had one metal 6L6 and one 6L6GC glass in a push-pull output. A very bad idea!
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On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am, wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.

On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.

Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?
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On 1/01/2020 4:20 am, wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.

Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.


--
Trevor Wilson
www.rageaudio.com.au


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Do you sell boutique cables and interconnects?

Peter Wieck
Melrose Park, PA
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On 2/01/2020 7:41 am, wrote:
Do you sell boutique cables and interconnects?

Peter Wieck
Melrose Park, PA


**Oops. Make that AUS$20.00/Metre pair:

https://www.wagneronline.com.au/ster...ctors/9435/fl/

Excellent quality cables. I choose them because they are robust, well
made and rarely cause problems. Foil and braid shielding.

I have no time for bull****, like cheap, ****ty, Chinese tube amps.

As for speaker cables, this is what I sell and recommend:

https://au.rs-online.com/web/p/coaxial-cable/2228654/

Low resistance and low inductance. And, low cost. PITA to terminate
though. FAR superior to most commercial speaker cables. Costs range down
as low as AUS$3.00/Metre.

Is that what you mean by "boutique"? Or are you thinking of something else?

--
Trevor Wilson
www.rageaudio.com.au
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On Wednesday, January 1, 2020 at 4:01:53 PM UTC-5, Trevor Wilson wrote:

**No. The most expensive cable I sell costs AUS$50.00/Metre pair. I
justify it, based on the fact that it uses good quality, PE insulated
copper, hand soldered, quality connectors.

What's your point? Are you seriously trying to defend the use of a
cheap, ****ty, Chinese tube amp in any good quality system?

You're fighting a losing battle. I've worked on more of these ****-box
amps than I care to think about. They, in many cases, look quite nice
(if you like that kind of style), but they introduce unacceptable levels
of (linear and non-linear) distortion.

FWIW: I have listened to a number of well built, very high performance
tube amps over the years (blind and sighted tests). In some cases, when
the speaker load was suitably benign, the tube amps performed as well as
a significantly less expensive SS amp. In most cases, the tube amps
performed worse.



http://www.rageaudio.com.au/index.php?p=1_4 From your website, so, presumably something that you are selling. Making you both a hypocrite and a liar.

My *point* is that this is a hobby. That there are multiple ways to enjoy it using multiple means and methods. If Eric chooses to use and enjoy a (truly) wretched bit of Chinese equipment - not my first choice, either - then it is his privilege to do so. And not have some lying asshole get up on his high horse about it.

Seldom do I resort to such language, but in this case, you well-and-truly deserve it.

At this point, I have no less than nine (9) amps in active service, being two brute-force amps, solid-state. Four moderate amps, solid-state, and three tube amps, ranging from 75 to 15 wpc/rms. I happen to enjoy all of them, largely for different reasons and under different conditions, and into different speakers.

Peter Wieck
Melrose Park, PA
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On 2/01/2020 8:24 am, wrote:
On Wednesday, January 1, 2020 at 4:01:53 PM UTC-5, Trevor Wilson wrote:

**No. The most expensive cable I sell costs AUS$50.00/Metre pair. I
justify it, based on the fact that it uses good quality, PE insulated
copper, hand soldered, quality connectors.

What's your point? Are you seriously trying to defend the use of a
cheap, ****ty, Chinese tube amp in any good quality system?

You're fighting a losing battle. I've worked on more of these ****-box
amps than I care to think about. They, in many cases, look quite nice
(if you like that kind of style), but they introduce unacceptable levels
of (linear and non-linear) distortion.

FWIW: I have listened to a number of well built, very high performance
tube amps over the years (blind and sighted tests). In some cases, when
the speaker load was suitably benign, the tube amps performed as well as
a significantly less expensive SS amp. In most cases, the tube amps
performed worse.



http://www.rageaudio.com.au/index.php?p=1_4 From your website, so, presumably something that you are selling. Making you both a hypocrite and a liar.

**I figured you would refer me to that. Those cables were provided to me
by a client who wanted me to sell them on consignment (no profit
margin). I duly advertised them as requested. I explained to him, at the
time, that I was unlikely to place them. After a few months, he
collected them. I have not had the opportunity to remove the ad from my
site. I'll get around to it. I am not overly concerned, as the ONLY
response I've had are from people like you, pointing out that ad. Not
one person has ever expressed any interest in purchasing the cables.



My *point* is that this is a hobby. That there are multiple ways to enjoy it using multiple means and methods. If Eric chooses to use and enjoy a (truly) wretched bit of Chinese equipment - not my first choice, either - then it is his privilege to do so. And not have some lying asshole get up on his high horse about it.


**A "lying asshole"? I cited the facts. Nothing more.



Seldom do I resort to such language, but in this case, you well-and-truly deserve it.


**Do I? How so?


At this point, I have no less than nine (9) amps in active service, being two brute-force amps, solid-state. Four moderate amps, solid-state, and three tube amps, ranging from 75 to 15 wpc/rms. I happen to enjoy all of them, largely for different reasons and under different conditions, and into different speakers.


**Good for you. Call a spade a spade and stop encouraging people to
persevere with cheap, ****ty, Chinese tube amps. In fact, there is no
sane reason to use ANY tube amp in a quality hi fi system.


--
Trevor Wilson
www.rageaudio.com.au


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On 1/1/20 3:33 PM, Trevor Wilson wrote:
**Good for you. Call a spade a spade and stop encouraging people to
persevere with cheap, ****ty, Chinese tube amps. In fact, there is no
sane reason to use ANY tube amp in a quality hi fi system.


Ya know, not everyone gives a rat's ass about having a "quality hi fi
system."

There are those of us that might be able to tell the difference, but
choose our "cheap piece of ****" system to listen to instead. Solid
State or tube.

Because to us, at the end of the day, it's just something to listen
to, not have some religious experience.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
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On 2/01/2020 8:45 am, Fox's Mercantile wrote:
On 1/1/20 3:33 PM, Trevor Wilson wrote:
**Good for you. Call a spade a spade and stop encouraging people to
persevere with cheap, ****ty, Chinese tube amps. In fact, there is no
sane reason to use ANY tube amp in a quality hi fi system.


Ya know, not everyone gives a rat's ass about having a "quality hi fi
system."


**Have you been reading the thread? The original poster is trying to
repair a cheap, ****ty, Chinese tube amp. There is no case that can be
presented to suggest that such an amplifier makes any kind of sense in a
system. ANY system. A cheap SS amp will cost less and provide superior
performance and reliability. Such an amp may not provide the same pride
of ownership though.



There are those of us that might be able to tell the difference, but
choose our "cheap piece of ****" system to listen to instead. Solid
State or tube.


**Sure. I use such a system for my TV listening. However, just a single,
decent quality, output transformer for a tube amp can easily cost more
than an entire, decent quality SS amp.


Because to us, at the end of the day, it's just something to listen
to, not have some religious experience.


**Again: Read the thread.


--
Trevor Wilson
www.rageaudio.com.au
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On 1/1/2020 4:23 PM, Trevor Wilson wrote:
....
I have no time for bull****, like cheap, ****ty, Chinese tube amps.
...


You seem to be spending time here ranting about them. What's it to you
if Eric chooses the amp he has. He's not asking for amp selection
advice. Quite the contrary. Let it go.
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On 2/01/2020 10:21 am, Bob Engelhardt wrote:
On 1/1/2020 4:23 PM, Trevor Wilson wrote:
...
I have no time for bull****, like cheap, ****ty, Chinese tube amps.
...


You seem to be spending time here ranting about them.Â* What's it to you
if Eric chooses the amp he has. He's not asking for amp selection
advice.Â* Quite the contrary.Â* Let it go.


**I care for several reasons:

* When people support dodgy manufacturers, it encourages those
manufacturers to foist yet more ****ty products to market.
* When people refuse to accept that they made a mistake by buying a
cheap, ****ty amplifier, they may encourage others to purchase similar
products. This sets a poor precedent, as there are many quite decent SS
amplifiers available, for quite decent prices.
* I have considerable experience with cheap, ****ty amplifiers (not just
tube ones). I fix 'em for a living. Owners can waste stupid amounts of
money trying to deal with poor manufacturing techniques and/or outright
stupid design. I am attempting to save the original poster considerable
angst.

[Anecdote] One of my mates learned to drive on a 1934 Ford V8. He has
many fond memories of the car. He is a wealthy guy and recently spent a
small fortune (AUS$100k) buying and fully restoring a nice example of
that car. After one, 100km trip in the car, he sold it. At a substantial
loss. It caused him a great deal of trouble and driving it was not what
he remembered.

We can all remember our first (few) amps. Mine were all tube ones (all
built by me). I loved them a lot. I can also remember the considerable
cost involved in replacing the tubes in a couple of them. KT88 tubes
were expensive back then. Now, original GE MOV KT88 tubes insanely
expensive. Chinese substitutes are ****.

Time to move on. Tubes are so 1950s. Great back then. Not so much now.

--
Trevor Wilson
www.rageaudio.com.au
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On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.

Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.


Someone's never had a good tube amp.


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They are on your website. You and no one but you is 100% responsible for the contents of your website.

Repeat:

Hypocrite.
Liar.
Pompous jackass.
Complete asshole.

Peter Wieck
Melrose Park, PA
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On 2/01/2020 12:07 pm, wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am,
wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.


Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, ****ty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a ****ty tube amp:

https://www.stereophile.com/content/...r-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another ****ty tube amp, with audible flaws):

https://www.stereophile.com/content/...r-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/...r-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/...r-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.



--
Trevor Wilson
www.rageaudio.com.au
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On Wed, 1 Jan 2020 17:07:43 -0800 (PST), wrote:

On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am,
wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.


Someone's never had a good tube amp.

One tube amp that I'm fond of is the McIntosh 275s. Rebuilt a pair of
them in the mid 80s and listened to them extensively before selling
them. They were the best sounding tube amps I've ever heard.
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Default More about that Chinese amp

Oh, good LORD, you are even more stupid than I thought.

I am not "defending" Chinese Junque at any level or in any way, shape or form. I am defending Eric's right to choose such equipment without criticism from you or anyone else. You share the same character flaw as your fellow ****** Phil Allison: When caught in a lie (or error of any sort), all you can do is lash out.

Peter Wieck
Melrose Park, PA


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Posts: 178
Default More about that Chinese amp

On 3/01/2020 1:21 am, wrote:
Oh, good LORD, you are even more stupid than I thought.

I am not "defending" Chinese Junque at any level or in any way, shape or form. I am defending Eric's right to choose such equipment without criticism from you or anyone else. You share the same character flaw as your fellow ****** Phil Allison: When caught in a lie (or error of any sort), all you can do is lash out.


**Here are YOUR words:

"Making you both a hypocrite and a liar."

"Hypocrite."
"Liar."
"Pompous jackass."
"Complete asshole."

Let us discuss my alleged "lashing out".

YOU are the one resorting to name calling. Not me. I have consistently
stated facts. Nothing more.

Eric certainly has every right to choose any junk he wants to own and
use. Just as I have every right (nay, duty) to explain what a
monumentally daft idea it is to use cheap, ****ty tube equipment in any
system. I do so on a regular basis, when presented with such junk for
service. The same goes for cheap (and sometimes not cheap), ****ty SS
equipment. I call a spade a spade. ****ty equipment should be jettisoned
and the owner can get on with life, rather than attempting to enjoy
something that will merely cause frustration.

You should also note that I very carefully showed why tubes, in general
and cheap, ****ty tube amps, specifically, are a stupid idea for a high
fidelity audio reproduction system in 2019. I did so, using published
graphs and an assumption that the readers of this group have the
technical abilities to understand those graphs and their implications
for real-world loudspeakers.

That is hardly "lashing out". Any suggestion that I have a resemblance
to one of my country-men is insulting. And wrong.

I note that you focus on ONE ad for cables on my site. Those cables were
placed there as a consignment sale for a client of some 30 years
standing. He ended up in the clutches of another dealer, who extolled
the virtues of the cables. I advised him, in no uncertain terms, that
the money would be better spent on room treatments, new speakers, or
some jewellery for his wife. He ignored me. After he realised the error
of his ways, he asked me to sell the cables for him. I agreed to do so
(reluctantly), due to our long relationship. He gave up waiting for me
to sell the cables and took them back. We have not spoken since. That
was more than a year ago. And yes, I should have removed the ad. I'll
get around to it.


--
Trevor Wilson
www.rageaudio.com.au
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Posts: 633
Default More about that Chinese amp

Give it a ****ing rest sport.
You'd do well to just shut the **** up now instead repeatedly
going on about how somebody's piece of kit is a piece of ****.

It's as simple as that.

The problem with Eric's "Chinese piece of ****" was a defective
EL34 tube.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
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Posts: 1
Default More about that Chine

01-03-20 06:46 Trevor Wilson wrote to about More about that
Chine
Howdy Trevor,

TW @MSGID:
TW @REPLY:
TW On 3/01/2020 1:21 am,
wrote:
-Snip-
TW You should also note that I very carefully showed why tubes, in general
TW and cheap, .... tube amps, specifically, are a stupid idea for a high
TW fidelity audio reproduction system in 2019. I did so, using published
TW graphs and an assumption that the readers of this group have the
TW technical abilities to understand those graphs and their implications
TW for real-world loudspeakers.

The BBS I use added this Conference last Year (2019).
I have looked at a few messages, but thought to post my first message here
about the Tube Amplifier topic.

When I was in High School (1956-1959) I told a friend that I wondered
if a Intercom systems Audio Output on one end could be ran through a Diode
positioned on one lead --|--

and the Audio Output at the other end have a Diode positioned --|-- to
have a Two Way conversation without either end having to flip the
Listen - Talk Switch, and no Audio Feedback could occur because of the
difference of Polarity.

My friend connected a Diode between an Audio Amplifier and a Speaker and
I remember the sound I heard was terrible, distorted iirc.

I built a Heathkit AA-32 Tubed Stereo Amplifier in the 1970's.
I can't remember if Heath offered Transitorized Stereo Amplifiers back then.

I've heard beautiful Audio from Both Transistorized and Tubed Hi-Fi System.
BUT
I always remember hearing the racket coming out of my friends speaker when
he used that Diode to demostrate what it would sound like.
AND
When I (even) see a advertisement for a Semiconductor Audio Amp I always
think why did a Square Wave sound so bad back then but doesn't in the gear
sold now.

73 de Ed W9ODR . .


.... Have you checked your smoke detector batteries & Fire Ext, LATELY?!
  #34   Report Post  
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Default More about that Chine

On Friday, January 3, 2020 at 7:15:21 PM UTC-5, Ed Vance wrote:
01-03-20 06:46 Trevor Wilson wrote to about More about that
Chine
Howdy Trevor,

TW @MSGID:
TW @REPLY:
TW On 3/01/2020 1:21 am,
wrote:
-Snip-
TW You should also note that I very carefully showed why tubes, in general
TW and cheap, .... tube amps, specifically, are a stupid idea for a high
TW fidelity audio reproduction system in 2019. I did so, using published
TW graphs and an assumption that the readers of this group have the
TW technical abilities to understand those graphs and their implications
TW for real-world loudspeakers.

The BBS I use added this Conference last Year (2019).
I have looked at a few messages, but thought to post my first message here
about the Tube Amplifier topic.

When I was in High School (1956-1959) I told a friend that I wondered
if a Intercom systems Audio Output on one end could be ran through a Diode
positioned on one lead --|--

and the Audio Output at the other end have a Diode positioned --|-- to
have a Two Way conversation without either end having to flip the
Listen - Talk Switch, and no Audio Feedback could occur because of the
difference of Polarity.

My friend connected a Diode between an Audio Amplifier and a Speaker and
I remember the sound I heard was terrible, distorted iirc.

I built a Heathkit AA-32 Tubed Stereo Amplifier in the 1970's.
I can't remember if Heath offered Transitorized Stereo Amplifiers back then.

I've heard beautiful Audio from Both Transistorized and Tubed Hi-Fi System.
BUT
I always remember hearing the racket coming out of my friends speaker when
he used that Diode to demostrate what it would sound like.
AND
When I (even) see a advertisement for a Semiconductor Audio Amp I always
think why did a Square Wave sound so bad back then but doesn't in the gear
sold now.

73 de Ed W9ODR . .


... Have you checked your smoke detector batteries & Fire Ext, LATELY?!



Not sure of your point but if you used a diode of any construction including a vaccuum tube diode, you would have heard the same distortion.
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You'd do well to just shut the **** up now instead repeatedly
going on about how somebody's piece of kit is a piece of ****.


Pretty early in the year for me to agree with you but I do. This is sci.electronics.repair, not how.to.go.to.bestbuy.and.give.MORE.money.to.the.ch inese.


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Posts: 12,364
Default More about that Chinese amp

On Thursday, 2 January 2020 01:33:30 UTC, Trevor Wilson wrote:
On 2/01/2020 12:07 pm, tabbypurr wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am, wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump..
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.


Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, ****ty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a ****ty tube amp:

https://www.stereophile.com/content/...r-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another ****ty tube amp, with audible flaws):

https://www.stereophile.com/content/...r-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/...r-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/...r-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.


I've also built a few tube amps and listened to a fair number of valve & tranny amps, though not 100s. Sure their foibles are different, with neither being perfect. My experience fwiw is I've never found any tranny amp that has the sound quality of a Quad II or a Sansui 500A. I used to be more involved in audio, not much now.


NT
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Posts: 178
Default More about that Chinese amp

On 5/01/2020 2:13 pm, wrote:
On Thursday, 2 January 2020 01:33:30 UTC, Trevor Wilson wrote:
On 2/01/2020 12:07 pm, tabbypurr wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am,
wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, ****ty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a ****ty tube amp:

https://www.stereophile.com/content/...r-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another ****ty tube amp, with audible flaws):

https://www.stereophile.com/content/...r-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/...r-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/...r-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.


I've also built a few tube amps and listened to a fair number of valve & tranny amps, though not 100s. Sure their foibles are different, with neither being perfect. My experience fwiw is I've never found any tranny amp that has the sound quality of a Quad II or a Sansui 500A. I used to be more involved in audio, not much now.


**I Would sincerely hope that no reputable amplifier manufacturer (tube
or SS) would try to build an amp that sounds as bad as either. Both have
serious measurable and audible flaws.


--
Trevor Wilson
www.rageaudio.com.au
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Posts: 1
Default More about that Chine

01-04-20 02:35 John-Del wrote to Ed Vance about More about that Chine
Howdy! John-Del,
-snip-
When I was in High School (1956-1959) I told a friend that I wondered
if a Intercom systems Audio Output on one end could be ran through a Diode
positioned on one lead --|--

and the Audio Output at the other end have a Diode positioned --|-- to
have a Two Way conversation without either end having to flip the
Listen - Talk Switch, and no Audio Feedback could occur because of the
difference of Polarity.

My friend connected a Diode between an Audio Amplifier and a Speaker and
I remember the sound I heard was terrible, distorted iirc.

I built a Heathkit AA-32 Tubed Stereo Amplifier in the 1970's.
I can't remember if Heath offered Transitorized Stereo Amplifiers back then.

I've heard beautiful Audio from Both Transistorized and Tubed Hi-Fi System.
BUT
I always remember hearing the racket coming out of my friends speaker when
he used that Diode to demostrate what it would sound like.
AND
When I (even) see a advertisement for a Semiconductor Audio Amp I always
think why did a Square Wave sound so bad back then but doesn't in the gear
sold now.


Jo Not sure of your point but if you used a diode of any construction
Jo including a vaccuum tube diode, you would have heard the same
Jo distortion.

I have always thought a Audio Sinewave going through a Transistor would
come out as a Squarewave, not a Sinewave.

To my way of thinking a Sinewave is Pure Audio, a Squarewave would make
the signal sound distorted (a bit?).

Does it happen as I imagine, or am I way off base.

I never seen the pattern of the output on an oscilloscope so I don't really
know.

73 de Ed W9ODR

.... There is always one more thing for Me to learn...
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Posts: 70
Default More about that Chinese amp

On Sun, 5 Jan 2020 15:37:08 +1100, Trevor Wilson
wrote:

On 5/01/2020 2:13 pm, wrote:
On Thursday, 2 January 2020 01:33:30 UTC, Trevor Wilson wrote:
On 2/01/2020 12:07 pm, tabbypurr wrote:
On Wednesday, 1 January 2020 20:18:43 UTC, Trevor Wilson wrote:
On 1/01/2020 4:20 am,
wrote:
On Tue, 31 Dec 2019 09:43:42 +1100, Trevor Wilson
wrote:

On 31/12/2019 9:34 am,
wrote:
On Tue, 31 Dec 2019 09:27:29 +1100, Trevor Wilson
wrote:

On 31/12/2019 5:50 am,
wrote:
On Tue, 31 Dec 2019 05:21:03 +1100, Trevor Wilson
wrote:

On 31/12/2019 4:45 am,
wrote:
Well, I peeked inside the amp and took off the transformer covers.
There are indeed 3 transformers. From what folks have said I half
expected to find some sort of weights under the xmfr covers because
the amp is so heavy. Nope, just copper and iron.
Inside the amp are no solid state devices but for the Bluetooth
module, which connects to the input through a relay. So the amp
switches automatically between inputs depending on whether the
Bluetooth module is recieving a signal.
On to the tubes. I turned the amp on again last night and just
listened. After a while, maybe 45 minutes, I heard a crackle. Looking
carefully at the tubes I noticed that one of the EL34 tubes was
glowing brighter at the top than the other EL34 tube. There is a mica
disc in the top of the tube and a little of the filament protrudes
through a small hole in the mica. And this is what was glowing
brighter.
I tapped the tube and heard the noise coming out of just the left
speaker. Tapping the right side tube produced no noise.
I though that maybe one tube was getting more voltage than the
other so I waited for things to cool down and then swapped tubes. The
same tube got brighter but was now on the right side. So the tube must
be bad because the problem travels with the tube and the same tube
gets brighter no matter which side it is plugged into.
So, anybody have suggestions on tubes? I'm not an audiophile. My
hearing isn't good enough. I don't think matched pair tubes would make
any difference to me ears. But I can hear well enough so a fairly high
quality tube set would be desirable. And I do think I should get a
pair so that they will hopefully last tghe same amount of time.
Thanks,
Eric


**Sure. Dump it and buy a decent solid state amp. Almost anything will
be far more reliable and better sounding. Why bother with a cheap,
Chinese tube amp?
Because I like it. It sounds good.

**How do you know? Have you compared it to a decent, inexpensive solid
state amp? Are you certain that it is not simply acting as an expensive,
unreliable filter?

People spontaneously comment on
how good it sounds.

**How would they know? By a very considerable margin, loudspeakers and
room acoustics, dominate the sound of a system. All amplifiers, unless
they are faulty (like cheap, ****ty tube amps) sound very similar.
Particularly to listeners who have little of no familiarity with the
system.


Not how it sounds almost as good as a solid state
amp. And I like tubes.

**Well, I guess we're different. I like my system to provide a close
illusion of the original musical event. No tone controls and no
(audible) distortion. If that result can be achieved with tubes (and it
can, but it costs a lot), then great. SS does it cheaper and more reliably.

Are you grumpy today?

**Well, yes, but that's another story. I'm very angry with my global
warming denying government. I'm stuck with the morons for a few more
years. Just as Americans are stuck with man with the intellect and
maturity of a 10 year old boy for POTUS. Still, there is hope. Not much
though.

I suggest you try a decent, inexpensive SS amp. Dump the tubes. Good
tube amps do sound pretty damned good. Trouble is, they are REALLY
expensive. For budget sound systems, SS does it better.
On the 1st Satuday in August I will be roasting my 25th pig. It's an
annual party. Why don't you fly up and camp out? We have 10 or 12
wooded acres. I have an extra tent. It's a good party and you can
listen to my ****ty tube amp and grouse about it while we grouse about
our ****ty "leaders". I'm sure the amp will sound better than Trump.
Eric


**Thank you, but no thanks. Pork is not a meat I like to eat.

Have you tried a decent, but inexpensive SS amp?

I'd rather listen to, well, ANYTHING, but Trump.
Yeah. I have a decent SS amp. Good speakers on it too. I still like my
tube amp. No accounting for taste, eh?


**Indeed. Your tube amp is acting as an expensive, unreliable tone
control. When you finally realise that, you may decide that another
approach is appropriate. Or not.

Think about it logically: EVERYTHING in front of your tube amp is solid
state. There are literally hundreds of semiconductor junctions in the
recording chain and any digital reproduction devices in your part of the
chain. The only thing your tube amp is doing, is to alter the original
sound, via linear and non-linear introduced distortion.

For me and my system, ALL forms of distortion interfere with the
original musical event and are not tolerated.

I get the attraction of tube amps to some people. They look different
and they have this retro appeal to hipsters and others. Sonically, they
are a waste of time, money and effort.

Someone's never had a good tube amp.


**Now you're just being silly. I've had the opportunity to listen to a
VERY wide range of amplifiers in my systems (numbering in the hundreds).
More than most, as my job is fixing them. I listen to all of them as
part of my test procedure. I've been servicing tube amps for more than
50 (gulp) years. I've built few too. In fact, I can tell you that a
REALLY good tube amp, when driving suitably benign impedance speakers,
will sound almost indistinguishable from a good SS amp. In fact, I was
fooled once. I thought I was listening to a Krell, when I was listening
to a rather good Audio Research. Here's the thing:

Really good tube amps sound just like really good (or even not so good)
SS amps. I can state that from personal experience.

Cheap, ****ty tube amps sound very different from really good tube amps
(and most SS amps). They sound different because they introduce various
forms of distortion.

Look at the frequency response curve, when operating into a typical
speaker load (black curve), of a ****ty tube amp:

https://www.stereophile.com/content/...r-measurements

I chose that amp, because it was easy to find on the Stereophile site.
There are many more examples.

Here is the response of another ****ty tube amp, with audible flaws):

https://www.stereophile.com/content/...r-measurements

Here is the response of an amp that I felt was acceptable in my system
(still far from perfect):

https://www.stereophile.com/content/...r-measurements


Here is the response of a cheap SS amp, which I felt sounded as good as
ANY tube amp (power output limitations excepted):

https://www.stereophile.com/content/...r-measurements

Far from perfect, but not too horrible.

You'll note the audibly significant frequency response variations
inherent to most tube amps. This form of linear distortion is VERY
audible. And not acceptable to me. This and other distortions do not
exist in most competently designed SS amps.


I've also built a few tube amps and listened to a fair number of valve & tranny amps, though not 100s. Sure their foibles are different, with neither being perfect. My experience fwiw is I've never found any tranny amp that has the sound quality of a Quad II or a Sansui 500A. I used to be more involved in audio, not much now.


**I Would sincerely hope that no reputable amplifier manufacturer (tube
or SS) would try to build an amp that sounds as bad as either. Both have
serious measurable and audible flaws.

The 500A also had heat related drifting cap values in the MPX circuit
which caused intermittent stereo reception .
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