What are your favourite tube screamer mods?

[Brett]

You should be fine with the switching you have if you’re using off board bypass switches for each circuit. It may be a good idea to adjust your net labels so your CAD software shows the correct connections when you start your layout.

 

[neiltheseal]

Hello again.
I finally got around to putting this together and (as I had suspected) it doesn't work properly.

Would anyone be able to have a look at the schematic for me and give me some tips re why why it's not working? The most recent schematic is attached.

It passes signal so that's a win, however there is no gain. With an audio probe I have tracked the problem to IC1.1. The signal enters strong on pin 3 but comes out extremely weak from pin 1 and therafter.

I measured the voltages and they are as follows:

1. 7.8
2. 7.8
3. 0.2
4. 0
5. 7.6
6. 7.6
7. 7.6
8. 8.6

This seems to confirm the problem is here as I assume that pins 1,2,3,5,6 and 7 should be about 4.5v. I suspect this means that I need to bias the op amp but I have no idea how to do this.

Thanks!

 

[Blackboarcult]

Leg 2 of LoCut should go to VREF and not to ground. Although I suspect that this is only part of the issue, your Vref voltage is too high to be caused by this accidental ground connection. Double check that you have 1/2 V+ between R16 and R17, and track from there.

 

[nooneknows]

you are too much rude on the TS, it is a good pedal with a particular purpose, almost completely forgotten these days (driving a non master volume tube amp in a much more comfort zone) , I can't say any other use is wrong but just put it in the right context and it works pretty well.

Anyway, if you don't want to use it that way, the only mods I really like are:

1) getting rid of the input and output buffer (useless if you run with a mechanical true bypass switch)
2) a variable bass control or, at least, moving the bass cut corner lower, doubling the infamous 47nF cap to ground for example
3) adding a germanium diode or a schottky diode (same voltage more or less) on one side of the clipping stage to enhance harmonics

that's it.