Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for years.
I usually remember to turn one receiver off before turning the other one on.
But occasionally, I have forgotten to do this -- also no problem. Until last
night, that is. I powered up my second receiver while the first one was
still on and played some music through it and burned up something in the
first receiver. It started making a hum in the speakers and clearly smelled
of burning electronics. So I turned it off. When I got back to receiver one,
it too was non-responsive on both sets of speakers. It was still powered on
but nothing will come out of the speakers now. Not even through the
headphones. I took the top off and tested the three fuses that I could see
with a volt meter. All worked fine.
So ... is there anything obvious I should check, or should I just buy a new
one?
I hope I provided enough info.

P.S. - The receiver I care about is a Pioneer VSX 401 .

"Fred Mann" wrote in message
...
Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for
years.
I usually remember to turn one receiver off before turning the other one
on.
But occasionally, I have forgotten to do this -- also no problem. Until
last
night, that is. I powered up my second receiver while the first one was
still on and played some music through it and burned up something in the
first receiver. It started making a hum in the speakers and clearly
smelled
of burning electronics. So I turned it off. When I got back to receiver
one,
it too was non-responsive on both sets of speakers. It was still powered
on
but nothing will come out of the speakers now. Not even through the
headphones. I took the top off and tested the three fuses that I could see
with a volt meter. All worked fine.
So ... is there anything obvious I should check, or should I just buy a
new
one?
I hope I provided enough info.



If the fuses are ok then you blew the outputs. Fixable if they're decent
recievers, but probably not worth it if they're worth $100 or so.

Next time install some sort of switch on the output so that only one
reciever can be connected to the speakers at a time. I'm really surprised
you didn't blow up one or both amps sooner, even if one was turned off.

"James Sweet" wrote in message
news:U646i.77$2v5.40@trndny06...

"Fred Mann" wrote in message
...
Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for
years.
I usually remember to turn one receiver off before turning the other one
on.
But occasionally, I have forgotten to do this -- also no problem. Until
last
night, that is. I powered up my second receiver while the first one was
still on and played some music through it and burned up something in the
first receiver. It started making a hum in the speakers and clearly
smelled
of burning electronics. So I turned it off. When I got back to receiver
one,
it too was non-responsive on both sets of speakers. It was still powered
on
but nothing will come out of the speakers now. Not even through the
headphones. I took the top off and tested the three fuses that I could
see
with a volt meter. All worked fine.
So ... is there anything obvious I should check, or should I just buy a
new
one?
I hope I provided enough info.



If the fuses are ok then you blew the outputs. Fixable if they're decent
recievers, but probably not worth it if they're worth $100 or so.

Next time install some sort of switch on the output so that only one
reciever can be connected to the speakers at a time. I'm really surprised
you didn't blow up one or both amps sooner, even if one was turned off.


Thanks James!
Just curious ... what would actually have been destroyed in this scenario? I
believe every single speaker output was rendered non-functional - even
outputs that weren't hooked up. Also, there was no burning smell on the
"good" receiver.

"Fred Mann" wrote in message
...

"James Sweet" wrote in message
news:U646i.77$2v5.40@trndny06...

"Fred Mann" wrote in message
...
Hello,
I have speakers all over my house, wired to two seperate receivers .
One
speaker is wired to both receivers. This has not caused a problem for
years.
I usually remember to turn one receiver off before turning the other
one
on.
But occasionally, I have forgotten to do this -- also no problem. Until
last
night, that is. I powered up my second receiver while the first one was
still on and played some music through it and burned up something in
the
first receiver. It started making a hum in the speakers and clearly
smelled
of burning electronics. So I turned it off. When I got back to receiver
one,
it too was non-responsive on both sets of speakers. It was still
powered
on
but nothing will come out of the speakers now. Not even through the
headphones. I took the top off and tested the three fuses that I could
see
with a volt meter. All worked fine.
So ... is there anything obvious I should check, or should I just buy a
new
one?
I hope I provided enough info.



If the fuses are ok then you blew the outputs. Fixable if they're decent
recievers, but probably not worth it if they're worth $100 or so.

Next time install some sort of switch on the output so that only one
reciever can be connected to the speakers at a time. I'm really surprised
you didn't blow up one or both amps sooner, even if one was turned off.


Thanks James!
Just curious ... what would actually have been destroyed in this scenario?
I
believe every single speaker output was rendered non-functional - even
outputs that weren't hooked up. Also, there was no burning smell on the
"good" receiver.



Many amps have a protection circuit, if they detect a fault on one output,
the rest will be disabled until the fault is corrected. There also may be a
fuse further up the line somewhere, such as in the power supply area, but I
wouldn't count on it.

Fred Mann wrote:
snip

If the fuses are ok then you blew the outputs. Fixable if they're decent
recievers, but probably not worth it if they're worth $100 or so.

Next time install some sort of switch on the output so that only one
reciever can be connected to the speakers at a time. I'm really surprised
you didn't blow up one or both amps sooner, even if one was turned off.


Thanks James!
Just curious ... what would actually have been destroyed in this scenario? I
believe every single speaker output was rendered non-functional - even
outputs that weren't hooked up. Also, there was no burning smell on the
"good" receiver.


If you look at the answer again you'll see the word 'outputs'. This
refers to the output devices in your receiver(s). Different ones use
different types. Some have discrete transistor devices. If one of
those, the output transistors and possibly other components associated
with them are now defective.

Troubleshooting one of these is more difficult--but not as expensive to
fix as the other type--that type being a unit with most of the amplifier
circuitry encapsulated in an epoxy module.

Those modules are easier to troubleshoot because for the most part, the
devices which will fail in such a scenario are all within that one
module. Replacing the one unit will likely fix the problem. OTOH, the
price for the part is higher than the various discrete parts in the
first type. Replacement is more difficult in some cases because of
soldering the number of closely-spaced pins involved. Many of the
modules are discontinued and difficult to find.

jak

On 27 May, 00:55, "Fred Mann" wrote:

Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for years.
I usually remember to turn one receiver off before turning the other one on.
But occasionally, I have forgotten to do this -- also no problem. Until last
night, that is. I powered up my second receiver while the first one was
still on and played some music through it and burned up something in the
first receiver. It started making a hum in the speakers and clearly smelled
of burning electronics. So I turned it off. When I got back to receiver one,
it too was non-responsive on both sets of speakers. It was still powered on
but nothing will come out of the speakers now. Not even through the
headphones. I took the top off and tested the three fuses that I could see
with a volt meter. All worked fine.
So ... is there anything obvious I should check, or should I just buy a new
one?
I hope I provided enough info.

How silly. Next time put a couple of 4 or 8 ohm Rs onto your speaker,
and connect one amp via one of them and the other via the other.


NT

On 27 mayo, 01:55, "Fred Mann" wrote:
Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for years.
I usually remember to turn one receiver off before turning the other one on.

I hate to sound wise after the event, but that was a disaster just
waiting to happen.

you will need to troubleshoot the output stages of the amp. Good luck
- many amps drive even experienced techs to tears!

try eserviceinfo.com for schematics etc. And if you fix it, then make
the next thing you do adding a switch box of some kind into this
harebrained speaker circuit !
-B-

b wrote:

On 27 mayo, 01:55, "Fred Mann" wrote:

Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for years.
I usually remember to turn one receiver off before turning the other one on.


I hate to sound wise after the event, but that was a disaster just
waiting to happen.

you will need to troubleshoot the output stages of the amp. Good luck
- many amps drive even experienced techs to tears!

try eserviceinfo.com for schematics etc. And if you fix it, then make
the next thing you do adding a switch box of some kind into this
harebrained speaker circuit !
-B-

A lot of units have a processor reset sequence you need to go through
when it shuts down like that due to some over load..
Like holding in a couple buttons when you power it up and so on..
AS far as the other receiver generating smoke/smell, I'm sure that
doesn't share the same kind of protection as I just detailed out.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

"b" wrote in message
ups.com...
On 27 mayo, 01:55, "Fred Mann" wrote:
Hello,
I have speakers all over my house, wired to two seperate receivers . One
speaker is wired to both receivers. This has not caused a problem for
years.
I usually remember to turn one receiver off before turning the other one
on.

I hate to sound wise after the event, but that was a disaster just
waiting to happen.

you will need to troubleshoot the output stages of the amp. Good luck
- many amps drive even experienced techs to tears!

try eserviceinfo.com for schematics etc. And if you fix it, then make
the next thing you do adding a switch box of some kind into this
harebrained speaker circuit !
-B-



Thanks for all the replies. I think I'm going to throw in the towel on this
receiver.
Fred