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previous: Lou Are LED's like regular diodes?... -- 9/2/1999 6:58 AM

Re: LED'S

9/2/1999 12:55 PM
Dai Hirokawa	Re: LED'S Not sure if this will answer your question, but I tried LEDs in place of the small signal silicon diodes in a Rat once, and the sound became more uncompressed--also got more high end when playing harder. Something to do with capacitance. You are supposed to get more highs as more signal is pumped through them(and indeed, this did happen). This phenomenon was cool, but, I didn't like the loss in compression(seemed kind of backwards, since it seems the goodness of this sort-of-tube-emulating-type of pedal comes from an increase in compression and saturated-ness--LEDs have a higher threshold of where a signal is allowed to pass through). Probably good to use LEDs for clipping when you need more "cut", and it's also probably better to design them into a circuit that pumps a lot of signal through them. The Marshall Jubilee series is probably a real good example of LEDs being well-utilized. Oh yeah, I do remember that I also tried some way smaller-than-usual LEDs that were more compressed sounding which I liked better but there still wasn't enough compression with these, so didn't stick w/them, ultimately. Also, yellow and green ones seemed less compressed than red(don't know exactly why). God, I'm rambling, rambling, rambling. Hope it helped (at least a bit, maybe?). Dai Hirokawa

9/2/1999 12:55 PM

Dai Hirokawa

Re: LED'S

Not sure if this will answer your question, but I tried LEDs in place of the small signal silicon diodes in a Rat once, and the sound became more uncompressed--also got more high end when playing harder. Something to do with capacitance. You are supposed to get more highs as more signal is pumped through them(and indeed, this did happen). This phenomenon was cool, but, I didn't like the loss in compression(seemed kind of backwards, since it seems the goodness of this sort-of-tube-emulating-type of pedal comes from an increase in compression and saturated-ness--LEDs have a higher threshold of where a signal is allowed to pass through). Probably good to use LEDs for clipping when you need more "cut", and it's also probably better to design them into a circuit that pumps a lot of signal through them. The Marshall Jubilee series is probably a real good example of LEDs being well-utilized. Oh yeah, I do remember that I also tried some way smaller-than-usual LEDs that were more compressed sounding which I liked better but there still wasn't enough compression with these, so didn't stick w/them, ultimately. Also, yellow and green ones seemed less compressed than red(don't know exactly why). God, I'm rambling, rambling, rambling. Hope it helped (at least a bit, maybe?).

Dai Hirokawa

Replies:

Doc The Turbo Rat uses red LEDs for cli... -- 9/2/1999 1:56 PM