Marshall Superlead Very Bass Heavy / Woofy

[matt1969]

Hey all,

I posted in another thread about my Superleads's channel 2 (normal channel) being too bassy. Well, Its not channel 2. It behaves this way even when plugged into just channel 1with the bass control all the way off.
My input section @ V1 & V2 up to the 2nd stage all test good & for the life of me, can not find anything wrong.

I'm now investigating the 2nd stage.

Any suggestions? I'm going to look at the 0.022uF cap that is connected to the bass & treble pot to start, maybe piggyback another cap across it or something?

[Roe]

check the 470-560pf cap connected to the treble pot

[pdf64]

Is the range of control of all the tone controls normal, eg does the bass control go from too bassy at CCW to even more bassy at CW?

[Reeltarded]

lift the mid ground point and compare how much bass with tone stack disabled

[Reeltarded]

go from too bassy at CCW to even more bassy at CW?

lol I love this

[matt1969]

Is the range of control of all the tone controls normal, eg does the bass control go from too bassy at CCW to even more bassy at CW?

Yes. with the bass all the way off, it sounds real bassy then whe I turn the bass up, It gets more bassy.

[matt1969]

All of my tone controls are working normally.

[WhopperPlate]

Is this a clone or an original?

Check things that age…my first guess is always tubes …power tubes are the usual suspects…

Check bias
Check amp voltages
Check wall voltages

unless there is some intermittent connection somewhere down the line like you theorize , it’s probably simply aging parts somewhere within the system, especially if it’s an older amplifier . That’s my guess.

Good luck .

[matt1969]

Is this a clone or an original?

Check things that age…my first guess is always tubes …power tubes are the usual suspects…

Check bias
Check amp voltages
Check wall voltages

unless there is some intermittent connection somewhere down the line like you theorize , it’s probably simply aging parts somewhere within the system, especially if it’s an older amplifier . That’s my guess.

Good luck .

Thanks. yes this an original 74 Superlead. I have replaced some old components over the years such as failed plate resistors, leaking caps, rectifier diodes etc.... There are no caps leaking DC & voltages all checked within spec. I need to try some fresh tubes next.

[Stevem]

Wouldn't be the first time a old board has become conductive and blead off the high end.

[WhopperPlate]

Wouldn't be the first time a old board has become conductive and blead off the high end.

Good point

[matt1969]

So I lifted my amp's PCB and re-flowed every solder joint and now my amp sounds normal again!!! What a nightamre
Thanks for all of the input as it helped me troubleshoot.