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Vintage threads from the first ten years

previous: R.G. OK, had a chance to look at the sch... -- 10/4/1999 4:40 PM

Re: Name this pedal!?!?!?!

10/5/1999 1:49 PM
GFR	Re: Name this pedal!?!?!?! Nice explanation. Note the importance of the diodes at the bases of Q3 and Q4. If they were not there, the 0.01 caps from the phase splitter would charge with the first signal peaks and turn Q3 and Q4 off, and your peak detector would not work. Much like what happens with "blocking distortion" (grid clamping) in tube amps. There's a little trick on the Dynacomp to get more dynamic range out of the CA3080. The 15k/0.01u/1u network on the (+) input will send some highs to ground; as the signal ges to the (-) input the result is that the gain is lower for low frequencies (where you normally have more power in an audio signal). The attenuation at the input is frequency dependant. Then at the output you have a 150k/0.001 combo that will compensate this and try to make the response "flat" again. A "pre-emphasis/de-emphasis" thing.

10/5/1999 1:49 PM

GFR

Re: Name this pedal!?!?!?!

Nice explanation. Note the importance of the diodes at the bases of Q3 and Q4. If they were not there, the 0.01 caps from the phase splitter would charge with the first signal peaks and turn Q3 and Q4 off, and your peak detector would not work. Much like what happens with "blocking distortion" (grid clamping) in tube amps.

There's a little trick on the Dynacomp to get more dynamic range out of the CA3080.

The 15k/0.01u/1u network on the (+) input will send some highs to ground; as the signal ges to the (-) input the result is that the gain is lower for low frequencies (where you normally have more power in an audio signal). The attenuation at the input is frequency dependant. Then at the output you have a 150k/0.001 combo that will compensate this and try to make the response "flat" again. A "pre-emphasis/de-emphasis" thing.