Clipping LEDs for Tube Screamer - ??

[beatstrat]

I was just wondering what general opinion here is about using LEDs (as in std red 3mm) as part of the clipping diode section of a TS circuit.  I always read about the various configs of 1N4148s, 1N34, 1N400X - but have not read of anyone using an LED.  Any thoughts on this would be appreciated to satiate my interest.  Thanks. 

Right now I'm using two-in-series 1N4148s on one side and two-in-series 1N34s on the other.  I'm thinking of ditching the Ge's and installing a single Si in its place - time's been short lately and I just haven't had the chance to set down with it.  I'd like to smooth-out the drive a little; a single Ge was too smooth/too little output for my taste.  I'm thinking that the 3mm LED would be too 'rough'/too little drive, but am still curious as to why I've not heard of anyone using these in this dirt box.

Also - would increasing the tone cap value broaden/darken the range of the tone knob?  The whole thing is a little bright to my ears (w/strats, teles > 6L6 amp).  I've got IC pin #2's R @ 3K3 and the associated cap at 0.1uF for a little more grind and upped the value of the clipping diode's parallel cap to 100pF with warming that section up in mind (not sure I heard a change or not - maybe too little value change).

I play clubs, etc (~15 nights a month) - as an idea of what my 'user status' is.

Thanks again.

[MartyMart]

Here's my personal "Fave" for the TS-9 type circuit :
1 X 1N4148 one way and 1 X 1N4001 the other, so a bit "asymetrical" and
a nice volume lift, clear lower gain and a nice "gritty" drive above 12 o'clock
on the gain pot.
The rest of your changes seem good, I have my tone pot at about 10/11 oclock
and that works for me .... gtr/amp etc etc

MM.

[beatstrat]

Thanks, MartyMart.  I found an interesting link today - you all may know/have seen this already, but thought I'd share anyway: http://www.geocities.com/SunsetStrip/Studio/2987/fatts.html - seems to be a pretty hip mod that adds/allows low freqs at low gain levels; but at higher gain settings, the bass is rolled off like the std TS circuit.  Looks like all it involves is adding a 560K Ohm resistor across the clipping diodes.

[343 Salty Beans]

I dig how one simple, two-cent component can add a whole new level to a pedal.

It's why this hobby rocks.

[wampcat1]

Thanks, MartyMart.  I found an interesting link today - you all may know/have seen this already, but thought I'd share anyway: http://www.geocities.com/SunsetStrip/Studio/2987/fatts.html - seems to be a pretty hip mod that adds/allows low freqs at low gain levels; but at higher gain settings, the bass is rolled off like the std TS circuit.  Looks like all it involves is adding a 560K Ohm resistor across the clipping diodes.

Well... a little more than just the resistor. What you are doing is removing the gain pot and subbing the resistor instead. then, add a 47k pot in series with the RC network there ( .047uf/4.7k on stock pedal). This is the same area that many change to give it the sound of 'adding' more bass or distortion.

In regards to that mod, that's the same basic idea the tube reamer is doing (see www.runoffgroove.com ), though many other pedals do something similar (distortion plus, od250, microamp, etc). The bad thing is that with the 'gain' knob down low, it is going to be muddy as all get out, IMO, unless you change that same RC network. Some like it though, especially if they usually just crank the gain up. If you are trying to get more gain, though...change the gain pot to a 1m, change the rc network there from a .047uf/4.7k to a 4.7uf/470 ohm.

bw

[burnt fingers]

I modded my tube reamer so that I am running a 1n4148 and a 1k resistor on one side and a 1n914 on the other side.   

Scott

[WGTP]

To me, it seems like a good idea to replace the resistor in parallel with the diodes (560K) with a 500K pot.  Then you can balance the bass response with the gain. 

I tend to use higher threshold clippers for more dynamic response, asymmetry and less noise. 1 LED and 1 SI or GE. 

[beatstrat]

Thanks, All.  I'm pretty sure I may be seen as heretical or at least crazy, but I have found that I dig the sound of the original chip that came in my TS-9 RI - the 75558P.  I installed a socket when I first got the pedal and have installed a few diff ICs - notably the 4558 and 4559.  From all that I'd read, I thought the 4559 would be 'just' what I was looking for, but that wasn't the case.  For some reason, my pedal sounds best with the 75558P chip.  Everything else seems to be too bright/fizzy (and almost glitchy) sounding.

[smank]

Why heretical? I think when we mod our pedals we need to hear the difference by ourself and everyone can choose the real component that really give us a good taste.
In my TS clone I normally use the TI RC4558, because this is my taste. But they sounds good also with the LM833 opamp.

[wampcat1]

Why heretical? I think when we mod our pedals we need to hear the difference by ourself and everyone can choose the real component that really give us a good taste.
In my TS clone I normally use the TI RC4558, because this is my taste. But they sounds good also with the LM833 opamp.

Absolutely. *SOME* people like the 4558 or it's variety, some don't. I like the TL072's in place of 4558 but that's just my preference. Some swear by the Burr Brown chip. As long as *you* like it, that's all that counts!

bw