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j r powell July 21st 10 02:55 PM

Paralleled Amplifier Wiring
 
Hi,
I have a small stereo amplifier which came with two tiny 4ohm 3watt speakers.
I'd like to combine the two channels of the amp in order to drive one, slightly
larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would be
required - combining the two outputs together. I have read that small resistors
are required in parallel configuration, to enable proper current sharing between
the amplifiers, as without them the two amps would fight each other and
overheat. Can anyone tell me the correct values for these resistors, and where
they should be placed?

thanks,
jamie.
--

PS. If your name is Dave Plowman, do not reply.



Arfa Daily July 22nd 10 12:48 AM

Paralleled Amplifier Wiring
 


"j r powell" wrote in message
...
Hi,
I have a small stereo amplifier which came with two tiny 4ohm 3watt
speakers.
I'd like to combine the two channels of the amp in order to drive one,
slightly larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would
be required - combining the two outputs together. I have read that small
resistors are required in parallel configuration, to enable proper current
sharing between the amplifiers, as without them the two amps would fight
each other and overheat. Can anyone tell me the correct values for these
resistors, and where they should be placed?

thanks,
jamie.
--

PS. If your name is Dave Plowman, do not reply.



How very rude ... d :-\

Arfa


Arfa Daily July 22nd 10 12:48 AM

Paralleled Amplifier Wiring
 


"j r powell" wrote in message
...
Hi,
I have a small stereo amplifier which came with two tiny 4ohm 3watt
speakers.
I'd like to combine the two channels of the amp in order to drive one,
slightly larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would
be required - combining the two outputs together. I have read that small
resistors are required in parallel configuration, to enable proper current
sharing between the amplifiers, as without them the two amps would fight
each other and overheat. Can anyone tell me the correct values for these
resistors, and where they should be placed?

thanks,
jamie.
--

PS. If your name is Dave Plowman, do not reply.



How very rude ... d :-\

Arfa


j r powell July 22nd 10 12:55 AM

Paralleled Amplifier Wiring
 

"Arfa Daily" wrote in message
news:KHL1o.42481$AS4.24133@hurricane...


"j r powell" wrote in message
...
Hi,
I have a small stereo amplifier which came with two tiny 4ohm 3watt speakers.
I'd like to combine the two channels of the amp in order to drive one,
slightly larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would be
required - combining the two outputs together. I have read that small
resistors are required in parallel configuration, to enable proper current
sharing between the amplifiers, as without them the two amps would fight each
other and overheat. Can anyone tell me the correct values for these
resistors, and where they should be placed?

thanks,
jamie.
--

PS. If your name is Dave Plowman, do not reply.



How very rude ... d :-\


Well... he follows me around usenet and trolls me.



David Nebenzahl July 22nd 10 01:24 AM

Paralleled Amplifier Wiring
 
On 7/21/2010 6:55 AM j r powell spake thus:

I have a small stereo amplifier which came with two tiny 4ohm 3watt speakers.
I'd like to combine the two channels of the amp in order to drive one, slightly
larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would be
required - combining the two outputs together. I have read that small resistors
are required in parallel configuration, to enable proper current sharing between
the amplifiers, as without them the two amps would fight each other and
overheat. Can anyone tell me the correct values for these resistors, and where
they should be placed?


Have you tried simply using a pair of 8-ohm speakers with the amp?
Chances are they'd work (less power, but shouldn't harm the amp).


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

j r powell July 22nd 10 01:29 AM

Paralleled Amplifier Wiring
 

"David Nebenzahl" wrote in message
.com...

Have you tried simply using a pair of 8-ohm speakers with the amp? Chances are
they'd work (less power, but shouldn't harm the amp).


I have, but then the audio output is too quiet for my requirements.



William Sommerwerck July 22nd 10 01:33 AM

Paralleled Amplifier Wiring
 
Have you tried simply using a pair of 8-ohm speakers
with the amp? Chances are they'd work (less power,
but shouldn't harm the amp).


I have, but then the audio output is too quiet for my requirements.


I'm not being sarcastic -- but how do you know that paralleling the outputs
will produce a significant increase in power? Ignoring the very pertinent
question of how to do this /correctly/, the most you could get is a 3dB
increase, which is plainly audible, but hardly a large increase.



j r powell July 22nd 10 01:56 AM

Paralleled Amplifier Wiring
 

"William Sommerwerck" wrote in message
...
Have you tried simply using a pair of 8-ohm speakers
with the amp? Chances are they'd work (less power,
but shouldn't harm the amp).


I have, but then the audio output is too quiet for my requirements.


I'm not being sarcastic -- but how do you know that paralleling the outputs
will produce a significant increase in power? Ignoring the very pertinent
question of how to do this /correctly/, the most you could get is a 3dB
increase, which is plainly audible, but hardly a large increase.


A small increase is better than nothing.



William Sommerwerck July 22nd 10 02:07 AM

Paralleled Amplifier Wiring
 
Have you tried simply using a pair of 8-ohm speakers
with the amp? Chances are they'd work (less power,
but shouldn't harm the amp).


I have, but then the audio output is too quiet for my requirements.


I'm not being sarcastic -- but how do you know that paralleling the
outputs will produce a significant increase in power? Ignoring the
very pertinent question of how to do this /correctly/, the most you
could get is a 3dB increase, which is plainly audible, but hardly
a large increase.


A small increase is better than nothing.


No, it isn't. Not when it requires a lot of work, and will be only slightly
audible.

"Forget about the whole thing." -- The Lady from Philadelphia



j r powell July 22nd 10 02:10 AM

Paralleled Amplifier Wiring
 

"William Sommerwerck" wrote in message
...
Have you tried simply using a pair of 8-ohm speakers
with the amp? Chances are they'd work (less power,
but shouldn't harm the amp).


I have, but then the audio output is too quiet for my requirements.


I'm not being sarcastic -- but how do you know that paralleling the
outputs will produce a significant increase in power? Ignoring the
very pertinent question of how to do this /correctly/, the most you
could get is a 3dB increase, which is plainly audible, but hardly
a large increase.


A small increase is better than nothing.


No, it isn't. Not when it requires a lot of work, and will be only slightly
audible.


Fitting resistors is hardly a lot of work. I just need someone who knows their
stuff, to answer my original question.




David Nebenzahl July 22nd 10 02:38 AM

Paralleled Amplifier Wiring
 
On 7/21/2010 6:10 PM j r powell spake thus:

"William Sommerwerck" wrote in message
...

I'm not being sarcastic -- but how do you know that paralleling the
outputs will produce a significant increase in power? Ignoring the
very pertinent question of how to do this /correctly/, the most you
could get is a 3dB increase, which is plainly audible, but hardly
a large increase.


A small increase is better than nothing.


No, it isn't. Not when it requires a lot of work, and will be only slightly
audible.


Fitting resistors is hardly a lot of work. I just need someone who knows their
stuff, to answer my original question.


So, William, what is the correct answer here (value of resistors)? I'm
curious now, too.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

William Sommerwerck July 22nd 10 02:53 AM

Paralleled Amplifier Wiring
 
I'm not being sarcastic -- but how do you know that paralleling the
outputs will produce a significant increase in power? Ignoring the
very pertinent question of how to do this /correctly/, the most you
could get is a 3dB increase, which is plainly audible, but hardly
a large increase.


A small increase is better than nothing.


No, it isn't. Not when it requires a lot of work, and will be only

slightly
audible.


Fitting resistors is hardly a lot of work. I just need someone who knows

their
stuff, to answer my original question.


So, William, what is the correct answer here (value of resistors)? I'm
curious now, too.


I don't see where I'm obliged to provide an answer, but here's what I
believe, to the best of my understanding...

Assuming that both channels have the same output impedance, and the output
levels are closely matched, then (if the outputs are directly paralleled)
there will be /no/ current flow from one channel into the other, and the
total amount of current that /could/ be delivered will be doubled. But if
the load impedance remains the same, there will be no increase in current
flow and no increase in volume level. You would need a speaker of half the
impedance to gain more power.

I think that's correct. Anybody want to agree or disagree?



tm July 22nd 10 03:09 AM

Paralleled Amplifier Wiring
 

"William Sommerwerck" wrote in message
...
I'm not being sarcastic -- but how do you know that paralleling the
outputs will produce a significant increase in power? Ignoring the
very pertinent question of how to do this /correctly/, the most you
could get is a 3dB increase, which is plainly audible, but hardly
a large increase.


A small increase is better than nothing.


No, it isn't. Not when it requires a lot of work, and will be only

slightly
audible.


Fitting resistors is hardly a lot of work. I just need someone who knows

their
stuff, to answer my original question.


So, William, what is the correct answer here (value of resistors)? I'm
curious now, too.


I don't see where I'm obliged to provide an answer, but here's what I
believe, to the best of my understanding...

Assuming that both channels have the same output impedance, and the output
levels are closely matched, then (if the outputs are directly paralleled)
there will be /no/ current flow from one channel into the other, and the
total amount of current that /could/ be delivered will be doubled. But if
the load impedance remains the same, there will be no increase in current
flow and no increase in volume level. You would need a speaker of half the
impedance to gain more power.

I think that's correct. Anybody want to agree or disagree?



Well, you sure don't want to use resistors to match it. Any gain would just
be
converted to heat.

ASSuming the impedance's were the same and you paralleled the outputs, you
would need a 1.5 to 8 ohm transformer to match the speaker.

But I agree with the first premise, it's hardly worth the 3 dB you might
gain.

T





--- news://freenews.netfront.net/ - complaints: ---

[email protected] July 22nd 10 03:18 AM

Paralleled Amplifier Wiring
 
On Jul 21, 5:56*pm, "j r powell" wrote:
"William Sommerwerck" wrote in message

...

Have you tried simply using a pair of 8-ohm speakers
with the amp? Chances are *they'd work (less power,
but shouldn't harm the amp).


I have, but then the audio output is too quiet for my requirements.


I'm not being sarcastic -- but how do you know that paralleling the outputs
will produce a significant increase in power? Ignoring the very pertinent
question of how to do this /correctly/, the most you could get is a 3dB
increase, which is plainly audible, but hardly a large increase.


A small increase is better than nothing.


The increase will be 0. Changing from 4 ohms to 8 will cut the power
in half because the voltage stayed the same and the current cut in
half because of the impedance change. Paralleling the amps raises
current capacity - which you don't need - and does nothing to increase
the voltage. In fact, your resistors will reduce it slightly. You need
a bigger amp.



Phil Allison[_2_] July 22nd 10 03:20 AM

Paralleled Amplifier Wiring
 

"j r powell"

I have a small stereo amplifier which came with two tiny 4ohm 3watt
speakers.
I'd like to combine the two channels of the amp in order to drive one,
slightly larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would
be required - combining the two outputs together.


** The only way to go here is to use "bridge mode".

Parallel wiring of the outputs is not only 100% useless it will almost
certainly destroy both amplifier channels.


I have read that small resistors are required in parallel configuration,
to enable proper current sharing between the amplifiers,


** Complete crap.

There is such of lot of it on the net you know.


..... Phil





William Sommerwerck July 22nd 10 03:28 AM

Paralleled Amplifier Wiring
 
I made a mistake -- for some reason I assumed this was a tube amp. (I don't
know why.)

Regardless, if the output levels are closely matched, one amp /will not/
pump current into the other. But to gain any increase in power, you'd have
to use a lower-impedance speaker.

There is also the possibility that, even with the levels matched, the amps
might not "like" looking at each other.

"Buy a decent amplifier that delivers the power you need." -- The Lady from
Philadelphia



[email protected] July 22nd 10 03:38 AM

Paralleled Amplifier Wiring
 
On Jul 21, 7:28*pm, "William Sommerwerck"
wrote:
I made a mistake -- for some reason I assumed this was a tube amp.

(I don't
know why.)

Regardless, if the output levels are closely matched, one amp /will

not/
pump current into the other. But to gain any increase in power,

you'd have
to use a lower-impedance speaker.


You are VERY WRONG on this.

There is also the possibility that, even with the levels matched,

the amps
might not "like" looking at each other.


Virtually a certainty.

"Buy a decent amplifier that delivers the power you need." -- The

Lady from
Philadelphia


This is good advice.



William Sommerwerck July 22nd 10 01:00 PM

Paralleled Amplifier Wiring
 
Regardless, if the output levels are closely matched, one amp /will
not/ pump current into the other. But to gain any increase in power,
you'd have to use a lower-impedance speaker.


You are VERY WRONG on this.


Why? You haven't changed the output voltage. If the amps are solid state,
their source impedance is much lower than that of the load, so there
wouldn't be any significant increase in current flow (that I know).



Allodoxaphobia[_2_] July 22nd 10 02:04 PM

Paralleled Amplifier Wiring
 
On Wed, 21 Jul 2010 18:53:58 -0700, William Sommerwerck wrote:

- snippage-

Assuming that both channels have the same output impedance, and the output
levels are closely matched,


.. and, assuming both outputs are _exactly_ in phase,

then (if the outputs are directly paralleled)
there will be /no/ current flow from one channel into the other, ....


Jonesy

whit3rd July 22nd 10 03:36 PM

Paralleled Amplifier Wiring
 
On Jul 21, 6:55 am, "j r powell" wrote:

I have a small stereo amplifier which came with two tiny 4ohm 3watt speakers.
I'd like to combine the two channels of the amp in order to drive one, slightly
larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type,


The power limit might not be the amplifier output stages,
but the common power supply. So, you'd just connect
to the left channel and ignore the other.

Alternately, you could transformer-couple and put the
left and right channel outputs in series (not parallel), to
get good drive into an 8 ohm speaker. Transformers,
though, aren't cheap. Doing this only gains you 3 dB,
it's scarcely worth the effort.

More efficient speakers (two of 'em, not one) is the
preferred solution if you don't like what you've got.

[email protected] July 23rd 10 07:15 AM

Paralleled Amplifier Wiring
 
On Jul 22, 5:00*am, "William Sommerwerck"
wrote:
Regardless, if the output levels are closely matched, one amp /

will
not/ pump current into the other. But to gain any increase in

power,
you'd have to use a lower-impedance speaker.

You are VERY WRONG on this.


Why? You haven't changed the output voltage. If the amps are solid

state,
their source impedance is much lower than that of the load, so

there
wouldn't be any significant increase in current flow (that I know).


If the output voltage is _slightly_ not matched, each amp will attempt
to correct it and push large currents into each other. HEAT. BANG.



GregS[_3_] July 23rd 10 02:22 PM

Paralleled Amplifier Wiring
 
In article , "j r powell" wrote:
Hi,
I have a small stereo amplifier which came with two tiny 4ohm 3watt speakers.
I'd like to combine the two channels of the amp in order to drive one, slightly

larger, 8ohm 4watt speaker.
The amp is of the non-bridgeable type, so I assume parallel wiring would be
required - combining the two outputs together. I have read that small resistors

are required in parallel configuration, to enable proper current sharing
between
the amplifiers, as without them the two amps would fight each other and
overheat. Can anyone tell me the correct values for these resistors, and where
they should be placed?

thanks,
jamie.


You forgot to give the power.

From quick reading of posts, to get more sound you can put 2- 8 ohm
speakers in parallel which will give 6 db increase over one
8 ohm.

You can bridge, say put 1-2 ohm resistors in series
with the speaker and use a bridge transformer on the input.
If you gave the minimum ohm spec of the amp, I could be more specific.
You also did not specify the output
type if the amplifier. Are the channels allready bridged ?

greg

Phil Allison[_2_] July 24th 10 05:30 AM

Paralleled Amplifier Wiring
 

"Greg ****head"

You forgot to give the power.



** It in the very first line of the original post.

You pathetic imbecile.



.... Phil





GregS[_3_] July 26th 10 02:27 PM

Paralleled Amplifier Wiring
 
In article , "Phil Allison" wrote:

"Greg ****head"

You forgot to give the power.



** It in the very first line of the original post.

You pathetic imbecile.



.... Phil




Reading.........

I have a small stereo amplifier which came with two tiny 4ohm 3watt speakers

Still reading.........................................

How tiny?

What color ??

greg

Phil Allison[_2_] July 26th 10 02:35 PM

Paralleled Amplifier Wiring
 
"Greg the trolling ****head"

You forgot to give the power.



** It in the very first line of the original post.

You pathetic imbecile.



I have a small stereo amplifier which came with two tiny 4ohm 3watt
speakers



** Wot a pathetic moron....




.... Phil





Michael A. Terrell July 27th 10 02:09 AM

Paralleled Amplifier Wiring
 

Phil Allison wrote:

** Wot a pathetic moron....



...and you'll never change.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.


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