Troubleshooting question

[Mike Christie]

I hope these are appropriate newsgroups for this kind of question; if
not, I'd be glad to know of a better place to post this.

Here's my problem. When I run a cable from my soundcard to my amp, I
can only get one channel. The cable is a 1/8" plug at the soundcard
end, splitting to two RCA phono plugs at the other; then it runs through
the wall about 70' and goes into two phono sockets in the amp. The
weird thing is that if I plug in the left phono only, I get the left
channel; if I plug in the right one only, I get the right channel; but
if I plug them both in, I only get the left channel!

I am positive that I am getting stereo signal through the 1/8-to-RCA
splitter, because I tried a track that has different vocals on each
channel, and each one came through. So there's no connectivity problem,
and no problem with the cables. I also tried plugging in my computer
speakers, and they work fine in stereo--I checked both channels.
However, something else weird then happens: I got a Y-splitter, male
1/8" to two female 1/8", to split the signal between the amp and
computer speakers so I could listen in both places. If I plug the
Y-splitter in the back of the soundcard, and the computer speakers in
one of the Y-splitter females, and leave the other Y-splitter female
unused, then the computer speakers work fine (i.e. I hear two stereo
channels, as they should be). This works with the computer speakers
connected to either of the two Y-splitter females. *But*, if I plug the
1/8"-to-RCA splitter that connects to the amp into the unused female,
then the computer speakers only produce one channel!

I am completely mystified. The only thing I can think of is that I am
short of power to drive a signal all the way down a 70' cable. But why
would that shut down one stereo channel completely and not the other?

Thanks in advance for any help.

Mike

[Kalman Rubinson]

Are the two channels wired out of polarity so that one is shorting the
other? How is the 1/8" plug wired?

Kal


On Sun, 03 Aug 2003 18:51:09 -0500, Mike Christie
> wrote:

>I hope these are appropriate newsgroups for this kind of question; if
>not, I'd be glad to know of a better place to post this.
>
>Here's my problem. When I run a cable from my soundcard to my amp, I
>can only get one channel. The cable is a 1/8" plug at the soundcard
>end, splitting to two RCA phono plugs at the other; then it runs through
>the wall about 70' and goes into two phono sockets in the amp. The
>weird thing is that if I plug in the left phono only, I get the left
>channel; if I plug in the right one only, I get the right channel; but
>if I plug them both in, I only get the left channel!
>
>I am positive that I am getting stereo signal through the 1/8-to-RCA
>splitter, because I tried a track that has different vocals on each
>channel, and each one came through. So there's no connectivity problem,
>and no problem with the cables. I also tried plugging in my computer
>speakers, and they work fine in stereo--I checked both channels.
>However, something else weird then happens: I got a Y-splitter, male
>1/8" to two female 1/8", to split the signal between the amp and
>computer speakers so I could listen in both places. If I plug the
>Y-splitter in the back of the soundcard, and the computer speakers in
>one of the Y-splitter females, and leave the other Y-splitter female
>unused, then the computer speakers work fine (i.e. I hear two stereo
>channels, as they should be). This works with the computer speakers
>connected to either of the two Y-splitter females. *But*, if I plug the
>1/8"-to-RCA splitter that connects to the amp into the unused female,
>then the computer speakers only produce one channel!
>
>I am completely mystified. The only thing I can think of is that I am
>short of power to drive a signal all the way down a 70' cable. But why
>would that shut down one stereo channel completely and not the other?
>
>Thanks in advance for any help.
>
>Mike

[Mike Christie]

I'm not particularly technical, so I'm not sure I understand what you
mean. The 1/8" to dual RCA is a cable I bought from Radio Shack; is it
likely there is something wrong with it? The 1/8" Y splitter is also
from Radio Shack, but I assume it's OK since I get the problem even when
it's not involved. Is there a way I can test the cable to see the
polarity? E.g by shorting the RCA end and seeing which way the current
runs at the miniplug end?

I'm not sure I understand why this would cause the problem. If they
were out of polarity (I think that means that the signal runs the
opposite direction from axial to circumference?) then wouldn't that just
give me out-of-phase sound at the speakers?

Thanks!

Mike

Kalman Rubinson wrote:
> Are the two channels wired out of polarity so that one is shorting the
> other? How is the 1/8" plug wired?
>
> Kal
>
>
> On Sun, 03 Aug 2003 18:51:09 -0500, Mike Christie
> > wrote:
>
>
>>I hope these are appropriate newsgroups for this kind of question; if
>>not, I'd be glad to know of a better place to post this.
>>
>>Here's my problem. When I run a cable from my soundcard to my amp, I
>>can only get one channel. The cable is a 1/8" plug at the soundcard
>>end, splitting to two RCA phono plugs at the other; then it runs through
>>the wall about 70' and goes into two phono sockets in the amp. The
>>weird thing is that if I plug in the left phono only, I get the left
>>channel; if I plug in the right one only, I get the right channel; but
>>if I plug them both in, I only get the left channel!
>>
>>I am positive that I am getting stereo signal through the 1/8-to-RCA
>>splitter, because I tried a track that has different vocals on each
>>channel, and each one came through. So there's no connectivity problem,
>>and no problem with the cables. I also tried plugging in my computer
>>speakers, and they work fine in stereo--I checked both channels.
>>However, something else weird then happens: I got a Y-splitter, male
>>1/8" to two female 1/8", to split the signal between the amp and
>>computer speakers so I could listen in both places. If I plug the
>>Y-splitter in the back of the soundcard, and the computer speakers in
>>one of the Y-splitter females, and leave the other Y-splitter female
>>unused, then the computer speakers work fine (i.e. I hear two stereo
>>channels, as they should be). This works with the computer speakers
>>connected to either of the two Y-splitter females. *But*, if I plug the
>>1/8"-to-RCA splitter that connects to the amp into the unused female,
>>then the computer speakers only produce one channel!
>>
>>I am completely mystified. The only thing I can think of is that I am
>>short of power to drive a signal all the way down a 70' cable. But why
>>would that shut down one stereo channel completely and not the other?
>>
>>Thanks in advance for any help.
>>
>>Mike
>
>

[Mike Christie]

Kal

> Are the two channels wired out of polarity so that one is shorting the
> other? How is the 1/8" plug wired?

A friend helped me figure out what you meant and why this was the
problem. Thanks very much -- that fixed it. Much appreciated.

Mike