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Micky[_3_] Micky[_3_] is offline
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Default What's wrong with computer speaker?

On Tue, 07 Jun 2016 20:10:00 -0400, Micky
wrote:


Combo answer to you and Ralph

On Tue, 7 Jun 2016 15:23:32 -0700 (PDT), Jeroni Paul
wrote:

Correct, the sound goes through the capacitor. It seems the amplifier sends a DC voltage to light up the led together with the audio signal. So if the led shines the wire is fine and the sound may be lost.in the capacitor.


Great. I'll replace it. Easy enough.

16volts 1000uF, I suppose the bag of caps in the basement for the last
30 years are too old to use???? If so I'll buy a new one.


I had two never-used caps of the right size in the basement and I was
too impatient to try to test them, so I just used one to replace the
original.

It didn't work.

Finally someone suggested what I already knew and forgot, to test the
speaker with a battery. It clicked the first time the battery was
touched to the plug but not again. Then clicked again when the plug
tip and ring were shorted to each other. So the speaker was good and
probably always good. I should have done this first.

And that means the left channel of the amplifier probably has a
problem.

Make sure you are sending an audio signal into the silent channel.


The sound card has both channels because I changed speakers and sound
comes out of both now.

That still leaves the possibility that something about the first-pair
speaker that works broke and it didn't pass the sound on to the other
one. They use different channels of the same amplifier.


That appears to be the case.


But it was hard** to open the speaker, so I'll do the cap first.


The grill along with its grill cloth was glued in place in the first
speaker, and I had to break two of the four plastic prongs to take it
off, which was needed to find the screws and take off the back. I
suspect the other one is glued too and don't want to break it open,
especially since it's going to a friend who only, for some reason,
wants one speaker. At least for now. So what good would it do to
fix it. I'll keep the second speaker, which has an RCA plug on it.

Thanks for the help.


**A friend wanted just one speaker, to put in his kitchen, with a wire
through the wall from the next room -- Yes, I suggested wireless
speakers but he wasn't interested -- I don't know if the stereo issue
has occurred to him, but he insisted one speaker***. So I'm giving
him the one that works, and if I fix the other one, I'll offer it to
him too. Back to opening the speaker: took out the two screws in
the back, scraped off the label in back but couldn't find another.
Tried to take off the speaker grill but it wouldn't come. A couple
days later, tried harder and broke two of the 4 plastic pegs that held
it in. Then I see that those two were glued in. Maybe it was falling
off, or maybe they're glued in at the factory. So I really don't
want to mess with the speaker that's still working, esp. since he
wants only one.

***So whether he knows he needs it or not, I've been looking for
software that will play a webstream and convert stereo to monaural. I
found one or two, so to test, I dl'd an MP3 of a train going from left
to right and back again. Sadly, on my system even in stereo it
doesn't sound like stereo. I have to work on that!

Thanks, both of you.