Has anyone fiddled with the 51pf cap across the clipping diodes in the op-amp loop? I'm wondering if a smaller value cap here would give a more present sound, I like a lot of the qualities of a tube screamer but think they tend to make the guitar sound disappear a little so I'm looking for ways to add brightness, although experimentation might show that's not the answer at all. I replaced the 1uf caps with film, changed one clipping diode to get a mismatch, changed the 51k and 4.7k resistors for more drive range, changed the cap before the op-amp to a 0.1uf, along with the op-amp and output resistors usually changed in a '808' mod. But it's still not doing it for me. Anyone tried changing the .2uf tantalum to ground after the clipping stage to a smaller cap?
Any other ideas?

There's a load of stuff about TS mods at Guitarkit.com diystompboxes and AMZ etc etc that might be of assistance if you haven't already seen them, I stuck 3 Ge diodes on one side and it seemes to make the sound clearer although it isn't as crunchy sounding to my ears but I didn't want a lot of drive anyway I just wanted rid of the mid hump, add a bit of bottom to the sound and remove some of the harshness, Tonepad have an essay on the TS as well.

Brian

Apologies, I forgot to mention The Technology of the Tube Screamer a@ Geofex in case you haven't seen it.

Brian

you can even remove the cap !
What that one does is smooth the highs a bit and could possibly make a bad opamp sound a little less harsh. Some hear this as being smooth. The jury is still out on this one as far as I am concerned.

What you are hearing is the diodes sucking the life out of your true guitar signal. Replace them with 3 mm red leds .

replace the drive pot (500k) with a 1 meg pot for even more dist.& drive

I know many like the idea of hifi type film caps in their screamer but all I want to know is why are you trying to clean up a distortion pedal ?

Imho , I think you would want a pedal to be as seemless as possible. Like an extention of the guitar / amp continueum. Not something riding on top of or below the guitar signal.

[This message was edited by GBlekas on October 18, 2003 at 08:38 PM.]

Thanks for the advice, I just picked up some 3 mm red leds at Radio Shack. I admit it's kind of ass backwards to get a clearer sound from a distortion or overdrive, but you have to admit we're not looking for mush with these things, I want a fatter sound with some edge and compression, a little grind to it, the big old 10 uf at the end of the Tube Screamer circuit is just passing what was created earlier, mushing up the tone and response with electrolytics can't help.

Try this, change your clipping diodes to 1N4001s. 2 on one side one on the other. The 1N4001s have a better openess to them than the 1n4148/914s do.
The red LEDs are going to give you a harder darker tone than the diodes. If you want to try something all together digfferent put thre clipping diodes on a mini toggle switch,on-off-on. replace one diode with 2 wires. run one wire to one end of a diode then connect the diode to the end of the switch. do the same for the other end except put 2 diodes on that end. Now you will have different clipping to choose from and the middle position of the switch is the tone of one diode which will give a big volume boost and a clearer tone. Or you could remove one of the clipping diodes and replace it with a wire jumper to get this effect.If you are looking to clear up the distrotion then try that.

There are so many things you can do. I can even get you a lot more distortion if you want but that doesn't sound like it's what your after.

Best of luck~!!

You could put a twelve position rotary switch in there with various diode/led configurations. However, this would obviously necessitate you remounting the board in a larger enclosure. I suggest a nylong coated aluminum Eagle enclosure. It has RF rejecting properties in the alloy. If you want, I'll post a schematic of how to wire the switch for a lot of great configurations. I've done this myself.

hello there, you could also try diode bounding, in other words use a resistor to separate the pair from connecting back on one side of the loop. i would try something between 680 ohms and 2.2k. this makes a big difference in the tone/vol. sucking effect of the clipping diodes. a popular diode combo is 1 1n914(1n4148) on one side and a 1n4001 + 1n34a germanium as a series pair on the other side---i think maybe fulltone uses this. anyway just some ideas. good luck rh