Quick Sanity Check - Moving Trimmer Off-Board

[frankie5fingers]

I thought I'd take the bias control to the enclosure, off the board.  It's a 500K trimmer.  I don't happen to have a standard 500K linear pot but do have a 500K reverse taper (C).  Two questions:
Since it's just a bias trimmer I can't see any reason not to use it, right?
Assuming it's not a problem, should I switch the #1 and #3 lugs?
Thanks

[jkokura]

First off, which pedal are you doing this with? Many bias controls shouldn't be adjusted, so which project are you doing this to?

Second, a trimmer is usually a linear (B) taper. Yes, you can use a C, it will give you finer control in the back end, and will come up quicker.

Can't say about using which lugs, because I don't know the project you're working on.

Jacob

[frankie5fingers]

It's the Pastyface, Soulbender version.
Thanks, Frank

[jkokura]

In that case, a Bias trimmer on the outside might be nice to have.

I couldn't quickly find the thread in which I posted this, but it may be helpful to do some experimenting with the range of the Bias control first. It's not an infinitely good sounding control, and there may be a very, very small window in which the Bias control even sounds good. That's why sometimes it's not a good idea to move the bias trimmer off board.

Try this. Put the pot or trimmer in place, then find the range at which the bias works. For example, maybe the fuzz sounds perfect at 250K bias, and anything between 200K and 300K is useable. In that case, you don't need a 500K pot, because only %20 of it's range is actually useable. Instead, you should use a 100K pot, and use a 200K resistor in series with the pot. Then, your knob's range will be between 200K and 300K resistance, and the knob at '12 o'clock' will sound perfect.

Otherwise, your knob would sound perfect at 12 o'clock, but only be useable between 11 and 1, rather than 7 to 5.

Make sense?

Jacob

[frankie5fingers]

Yup, sure does.  Thanks for that Jacob.  I'll try a couple before I box it up.
Thanks, Frank