Silicon Tonebender / James Tonestack Troubleshoot

[Hexjibber]

Hey all,

Just wanted to ask for some assistance troubleshooting a new build/layout I've done in Eagle. It's a silicon Tonebender / DH Hot Silicon (etc etc) that I swapped the standard tone stack out for a James one to have a bit more flexibility in controlling the tone. The good news is it fires up and works but the tone controls are way off, namely;

1) The Treble pot works in reverse and the range of the pot is all at one end as well as it being far too tinny and harsh for 75% of the travel. From looking at my schematic I think I've got the pot the wrong way round so that at least solves one problem but as for the second, everything I've read says to use Log pots in the James tone stack but my problem would seem to insinuate that I should have used Linear, would anyone agree?

2) The Bass pot works as intended just about, it's effect isn't all that noticeable to be honest as to me it only sounds good when fully clockwise, going back the other way just yields hollow emptiness! I've noticed that there is a significant increase in level/gain when the pot is turned fully clockwise, is this normal for a James tone stack or I have I done something wrong?

3) I changed the fat switch that swaps between input caps on the original for a pot with the same values as the Blackout Musket 'Focus' pot that does the same job but the effect isn't anywhere near as noticeable, what could be the reason for this?

Hoping you guys might be able to help, this is the first time I've tried to monkey around with a circuit and the result has left me a bit deflated!  I'm going to remove all the relevant parts and stick sockets in and see what does what but was wondering if someone would be able to shed a bit of light on where I've gone wrong!

Here's a link to the schematic;

https://dl.dropboxusercontent.com/u/42206482/Talisman%20v1.0.pdf

Cheers!
Graham

[Cortexturizer]

The colorsound overdriver uses a similar thing and it's Bass control works pretty much the same way you've described.

[pryde]

Experiment with the Duncan tone stack calculator so you can correctly interpret the frequency response.

http://www.duncanamps.com/tsc/

[Hexjibber]

Experiment with the Duncan tone stack calculator so you can correctly interpret the frequency response.

http://www.duncanamps.com/tsc/

Thanks, I've actually been fiddling around with that this afternoon, seems to make sense but I have to admit to being more of a 'by ear' kind of guy! I'm going to socket all the key components and just have a play around. That tone stack calculator has given me a much clearer idea of how it's all working though.

[pryde]

I agree  the ear is best but using the calculator might allow  you to see where your frequency  curve is at for a starting point.

[Hexjibber]

I agree  the ear is best but using the calculator might allow  you to see where your frequency  curve is at for a starting point.

Yeah I agree, I think my main problem with the calculator is I'm not really sure what I'm aiming for in the visual sense? I understand the curves and what they mean in relation to EQ but as for what sort of curves would represent the sound in my head I'm not quite sure! It's easy to describe however, i.e. plenty of bass, nice bit of cut from the mids and treble but not too harsh!

After the initial disappointment I'm actually quite excited about having a play around with the various values to see how it all fits together