Metropoulos Forum

Hey dear amp freaks,

I own a plexi clone and want to try a
250 k midpot instead of the 25k.

Can i use a laying around guitar (volume) pot?

I want to try if i can go from slightly scoop to 'normal 25k dimed' to boosted... wirh this pot.

I read it works on fender amps not marshall but it should work too, aint it?
Idea is to get more of a tweed sound if wanted (my amp has no negative feedback also)

Will the guitar pot be ok or do i need a special pot..
Log, linear, or audio?

Thanks alot... if you can point me to some topic that handles what i want, Thats fine too.

250k is too much.

Anyway, you can try with a 250k one, and try with resistors in parallel to lower the value.

try 50k

Thanks for suggestions guys!

1)so if i take a 50k pot.. or 100k
Which..
Linear. Audio or log?

2) so i can also try 250 k guitar pot. And when i want to lower the resistance i should put 2 of the same rs between the outside and the middle lug?

Or just between one side and middle?

Lets say i want 100k from 250k..
250 i thought would fit because there exists a 'raw' control in some amps that is basically a 250 mid pot.. i read about it.. i dont have to turn it up all the way..

The idea is a sweep from stock to midboost to almost completely bypassing tonestack..

Cheers

Just had another idea.

50k pot

And then a switchable large resistor to ground for almost completely bypassing the stack..

Do i can dial in some tones at the pot.. and then soloboost per footswitch..

The switch is already there.. 1m resistor.
Think this will be best solution..

Right? Because i crank the mid knob anway right now..

So i just have to ger the right kind of pot.. not sizewise but type wise... log. Audio . Or linear..

Thanks for suggestions

My favorite value for the midpot is 100k log - from zero to about halfway up it operates like a normal mid control, and as you turn up past that point you get a massive boost but it is still very controllable. A 250k log pot would give you similar results but is more difficult to control IMHO.

Cheers Stephan

anything from ca 27k to 36k is historically correct. most newer 50k pots read ca 45k

darkbluemurder wrote:My favorite value for the midpot is 100k log - from zero to about halfway up it operates like a normal mid control, and as you turn up past that point you get a massive boost but it is still very controllable.

Cheers Stephan

Thanks Stephan, i used the trick you suggedted in some other thread about a small to medium sized cap across the midpot to only boost mids and not so much highs.. worked like a charm on my 25k pot..

Would you advise to keeping it for the larger pot as well, or should i remove it or adjust the cap value? Of course i could test it but i'd live to hear your humble opinion.

Cheers Georg

GeekG wrote:

darkbluemurder wrote:My favorite value for the midpot is 100k log - from zero to about halfway up it operates like a normal mid control, and as you turn up past that point you get a massive boost but it is still very controllable.

Cheers Stephan

Thanks Stephan, i used the trick you suggedted in some other thread about a small to medium sized cap across the midpot to only boost mids and not so much highs.. worked like a charm on my 25k pot..

Would you advise to keeping it for the larger pot as well, or should i remove it or adjust the cap value? Of course i could test it but i'd live to hear your humble opinion.

Cheers Georg

To get the same sonic effect I would adjust the cap value to 1/4 th of the value used for the 25k pot.

Cheers Stephan