Solved Audio issue

jefflongo

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So unfortunately, one of my audio wires broke off and took some components with it. I searched for another relocation point and found one online. It works but that audio line is significantly quieter than the other one. Is there anything I can do about this?

Original relocation point
23.png

New relocation point
30.png

My board:
20170501_152213.jpg
 

jefflongo

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So I'm trying to trace out the audio lines in hopes of finding a solution. I think it goes something like this
audio.png


Audio goes from the AV IC to the amplifier IC. From the output of the IC, I believe it goes to the other side of the board to the filtering capacitors and then back to the bottom side of the board where it goes through those (parallel I think) resistors to the capacitor where it would go to the connector which was trimmed off. I was before pulling audio from the relocation point Ashen posted between C130 and R11 but since those broke off, I used the input leg of the AMP IC.

If this is the input signal, it would make sense that it is quiet because it's not amplified yet. But why is it suggested to use the input source of the audio instead of the output of the amp? Should I try pulling audio from the the filtering caps on the top of the board? Do I need to put a resistor and capacitor in series with the audio line to make up for the components that broke off? If I am mistaken of what I'm tapping audio from, what's the worst case scenario? For example, if I accidentally pull something that is not audio and input it to a tv, is it going to damage it?
 

The Next Guy

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Well if I recal correctly, the audio from the amp can sound pretty choppy when not given the 12V it wants. I'm pretty sure SS mentioned that a while ago on an old forum. It is recommended just to amplify the audio yourself. Am I right @ShockSlayer?
 

JacksonS

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Prettt much any of the points you found are good to use. Obviously if you take the audio at the output of the filtering caps, it may be filtered better, but that could be negligible. The same goes for all the other small capacitors and resistors; you can bypass them if you want becuase including them will most likely have a negligible effect.

If you were to accidentally feed a voltage supply directly into the TV, the worst case scenario is the TV breaks. But most likely the TV has filtering capacitors, like the GameCube, which will block any DC voltage and not let the direct voltage damage anything.
 

jefflongo

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Well if I recal correctly, the audio from the amp can sound pretty choppy when not given the 12V it wants. I'm pretty sure SS mentioned that a while ago on an old forum. It is recommended just to amplify the audio yourself. Am I right @ShockSlayer?
You're referring to the preamp which can run off as little as 5v but has worse audio quality when you go lower than 12v. That part is fine and is receiving voltage. I'm referring to the actual audio signal going to the amplifier.

Prettt much any of the points you found are good to use. Obviously if you take the audio at the output of the filtering caps, it may be filtered better, but that could be negligible. The same goes for all the other small capacitors and resistors; you can bypass them if you want becuase including them will most likely have a negligible effect.

If you were to accidentally feed a voltage supply directly into the TV, the worst case scenario is the TV breaks. But most likely the TV has filtering capacitors, like the GameCube, which will block any DC voltage and not let the direct voltage damage anything.
I'll try pulling audio from the filtering capacitor and see what happens.

EDIT: it worked :)
 
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