a very very weird problem

[Albrerta]

a very very weird problem (please move this to Class D, thanks)

The problem is one channel output lower than another, I know it's something with the preamp, because I just added a LDR attenuator on it.

I tested with another preamp, everything was fine, switching speaker cable from output of power amp, then the weak channel also switched, so safe to say it's not power amp

Now no matter how I switch interconnect cables, the input on power amp, the output on preamp, and the input on preamp, the weak channel always on the same side. It just doesn't make sense, for any issue with the preamp, I would expect the strong/weak channel swapping when I switch the interconnect cable, but why it didn't?

 

[analog_sa]

A test tone and a voltmeter will discard all weirdness bar the one in your ears

 

[Jay]

I tested with another preamp, everything was fine,

Full stop? Meaning: no weak channel with another preamp?

switching speaker cable from output of power amp, then the weak channel also switched, so safe to say it's not power amp

You mean: it is not the speaker? (Which part is the speaker test?)

Strange indeed. Have you got enough sleep lately?

 

[JonSnell Electronic]

I think you have answered your own question; "I know it's something with the preamp, because I just added a LDR attenuator on it".
I would remove it or at least balance the light sources.
Swapping the speakers over and the problem stays the same side? If so, the speaker is at fault.

 

[epicyclic]

Deleted previous message....my bad.