hi,
have modified some parts of a distortion circuit and have a few questions, about weather a part of the circuit is now obsolete.....
and also where some dynamics/headroom may have been lost with the modifications and if they can be re-gained some how. (still have no O.scope sorry)
the sound is very satisfactory except for sounding more compression. the three main alterations are,
(A) D3 & D4 from 1n4148 to 1n4001
(B) R1 from 470r to 1K (reduce gain)
(C) remove C28 10nf (no jumper/ open circuit )
some coupling values have also been changed and C6 27n is now a 5way selector switch ranging from 15n to 100n.
please see the circled high lighted schematic for the main changes.
wondering R25 & Q5 may be obsolete now?
maybe D3 D4 is responsible for too much compression?
any advice on how to re gain some dynamics would be appreciated.
cheers
have modified some parts of a distortion circuit and have a few questions, about weather a part of the circuit is now obsolete.....
and also where some dynamics/headroom may have been lost with the modifications and if they can be re-gained some how. (still have no O.scope sorry)
the sound is very satisfactory except for sounding more compression. the three main alterations are,
(A) D3 & D4 from 1n4148 to 1n4001
(B) R1 from 470r to 1K (reduce gain)
(C) remove C28 10nf (no jumper/ open circuit )
some coupling values have also been changed and C6 27n is now a 5way selector switch ranging from 15n to 100n.
please see the circled high lighted schematic for the main changes.
wondering R25 & Q5 may be obsolete now?
maybe D3 D4 is responsible for too much compression?
any advice on how to re gain some dynamics would be appreciated.
cheers
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am thinking if it would have been better to keep R1 value at 470r and increase R7 value to keep dynamics.
By definition distortion circuits reduce dynamics, that´s their job.
If you want more dynamics switch distortion OFF.
If you want less gain, simply lower RV1 (distortion) setting 1 notch or 2, that´s its job.
It´s part of a gyrator circuit which equalizes the pedal sound, by removing C28 you now lobotomized it.
IF you meant C6 , it would change gyrator boost frequency, but since you lobotomized it ......
Q5 function has effectively been destroyed by removing C28.
I think you are barking at the wrong tree here, just enjoy your distortion pedal as is, it has been designed by very qualified Engineers, and if you want to Mod it for good, study a lot until you reach their level.
Now if the goal is to Mod it for bad, just keep pulling parts at random.
It reminds me of the Hal scene at 2001 Space Oddissey when HAL brain parts were being pulled one by one.
YouTube
I bet if your pedal could talk it would tell you: "please stop Paul, I´m afraid".
If you want more dynamics switch distortion OFF.
No change expected.
Not needed.
If you want less gain, simply lower RV1 (distortion) setting 1 notch or 2, that´s its job.
Why would you do that
It´s part of a gyrator circuit which equalizes the pedal sound, by removing C28 you now lobotomized it.
C26 is shown as 220n ¿¿¿???
IF you meant C6 , it would change gyrator boost frequency, but since you lobotomized it ......
R25 is U1b bias reference, pulling it would be similar to smashing your hand with a hammer and then trying to play.
Q5 function has effectively been destroyed by removing C28.
I hope so, that´s their job.
I think you are barking at the wrong tree here, just enjoy your distortion pedal as is, it has been designed by very qualified Engineers, and if you want to Mod it for good, study a lot until you reach their level.
Now if the goal is to Mod it for bad, just keep pulling parts at random.
It reminds me of the Hal scene at 2001 Space Oddissey when HAL brain parts were being pulled one by one.
YouTube
I bet if your pedal could talk it would tell you: "please stop Paul, I´m afraid".
well it probably wouldnt since i built it from scratch i think its just happy to be alive,
yes i know the gyrator is disengaged that was the purpose.
why say altering it for bad without even hearing it common
By switching in the 1A doses in place of 150mA ones, you may have lost little headroom. If you'd accomplish the same with 7 of the original diodes in parallel to get the same 1A rating, for a given low current, the voltage drop would be less.
You could use pairs of diodes in series to increase the voltage before clipping starts. Or put a resistor in series with them to soften the clipping.
You could use pairs of diodes in series to increase the voltage before clipping starts. Or put a resistor in series with them to soften the clipping.
Or try OA47 germanium diodes. Or one Ge diode and another Si diode opposing.
Or even jFET (with G-S shorted).
I never got past Ge diodes, because I prefer the soft clipping with less IMD, compared with the hard clipping of Si diodes/overdriven OP amp sound.
Or even jFET (with G-S shorted).
I never got past Ge diodes, because I prefer the soft clipping with less IMD, compared with the hard clipping of Si diodes/overdriven OP amp sound.
cheers for the advice, I tried the leds before the 4001's. the pairs of 4001s in series worked really well. added a grounding switch in between the two pairs for harder distortion.