Begginner over here..

[MrSir]

I have been wanting to build a pedal for a long long time and I thought I'd start out whit this DOD 250 clone.
I thought I'd do it on a perfboard and then mount it in an enclousure.

http://www.tonepad.com/getFile.asp?id=115

I notice that the Dioeds are not in the parts list. It says "try different type of diodes for clipping"
So it doesn't matter witch diodes I use?

Also.. Is there like a universal circuit for expression pedals. Like M-audio's EX-P


Great Forum!  

Edit: I hate being such a beginner!
Where is the LED light?
Is it one of the diodes?

[caspercody]

You can use 1n914 diodes. Or use a switch and switch between diodes, leds, or mosfets. There are many ways to do the clipping.

[jdub]

Welcome! Great circuit to start with.  For simplicity you can use either silicon diodes (1N914, 1N4148, 1N400x, etc.), Ge diodes (1N34A, 1N270, etc.), or LEDs. to start. As caspercody said, MOSFETs trannies can also be used as clippers. All have different sound characteristics- in my Distortion + (very similar circuit) I have a switch to choose between 1N914s and 1N270s, and both sound great; you'll find that Ge diodes will not be as loud as Si, but have a "smoother" & (to my ears) mor "tube-like" sound.

As for the LED light, i assume you're referring to the LED staus indicator; this is part of the offboard wiring & isn't one of the clipping diodes.  At Tonepad, in the FX projects, click on "Offboard Wiring"- Fernando has several wiring digrams for jacks, switches, LEDs etc.

There's a ton of info on the circuit, and diode clipping in general, in the forum that a simple search will turn up.  Have fun.

[MrSir]

Thanks a lot for the help!

[Renegadrian]

I am currently building my second 250, this one too with the diode switch
1n914-4148 have that great "compressed" sound, lots of gain
LEDs give you more "headroom", "air", volume and clarity but less distortion.

[petemoore]

  Comes with a capacitor and a couple diodes, but see AMZ Labs Notebook for a host of options.
  The + portion of a signal wave is like a wave passing under a wall, or the wavetip getting knocked off as the wall gets lower, more wave slams into the wall. All wave energy that touches the wall is stopped, the clipped off portion is shunted to ground.
  Lowering the threshold reduces output.
  See FAQ and AMZ Labs notebook for options like assymetry and adjustment.
  A 100kb gain knob spreads out the distortion settings over the pot rotation at the expense of not reaching lower gain settings .