Have I wired my tone pot up wrong?

Started by mrahc_jftd, October 26, 2020, 03:36:49 AM

Previous topic - Next topic

mrahc_jftd

Hey hey! Back again.

So I'm continuing on my building quest. At the moment I'm back trying to put together the overdrive from Brian Wampler's 'How To Design A Basic Overdrive'.

So far it's pretty much sounding like I imagine it probably should. Issue I think I'm having is that the tone control is behaving interestingly.

When the pot is turned up completely, I get a pretty crazy squeal from the circuit. I only need to roll it off a little to get rid of it tho so it's no huge biggie.

Main hiccup is that when I roll it back, from maybe halfway to nil it basically sounds like the signal is in another room. Basically it loses a tonne of volume and gets reeeeeally dark sounding. Essentially there's just a really small window in which it sounds right.

The way I have it wired is (looking at it top down)
Right lug - Coming out of capacitor C3
Centre Lug - entering capacitor C29 then to ground
Leg Lug - out into the volume pot

I wonder if I've done that wrong? Or maybe it's something earlier on? I've also included a top down pic of the breadboard incase anyone happens to spot some dumb shit I might have pulled haha!

P.s(the green wires to the left are the tone pot)

Thanks guys ❤️❤️







antonis

#1
Nothing wrong with pot wiring..  :icon_wink:

When it's all the way up (wiper shorted to C3 positive plate), C29 is op-amp's output load..
(op-amps DO NOT like to drive capacitive loads - they frequently oscillate ..)

Try to place a series resistor, 1k say, on TL082 output..
(resistor presice value could be calculated according to 0.159/R*C29 for the higher cut-off frequency - Tone control is a simple LPF formed by C29 and pot left part resistance..)
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

mrahc_jftd

Thank you again!

This worked a charm 💪