Proton Amp L/C Marginal Bass, Heres a good one for ya!

Hi all

My Proton AM455 decided to lose a lot of bass from the left channel only.:blink: I did the usual things, switch the speakers from left to right, check all other inputs & listened for noise whilst adjusting the pots only to find it was common to the left channel only.
I was getting ready to swicth the output transistors from the left to right channel thinking that one of them was breaking down under load, this should if correct move the loss of bass to the right channel.
Before turning off the Amp I just happened to give the bass knob a good old flick & what do you know "HELLO BASS".
A good flush of all pots using a good circuit board cleaner that wont leave any residue as shown below & :applaud: all sweet, sounds better overall now. I guess it pays to check the basics first, just might save you a lot of time.
Cheers Wayne. :cheers:

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