can someone explain why my DRRI acts funny with these two pedals?

[ode2no1]

first off, everybody always complains about the bright cap on the vibrato channel and how it makes it so much less pedal friendly than the normal channel, but for some reason when i plug my soul bender clone into the normal channel of my amp it sounds TERRIBLE. it almost sounds like i have a buffered pedal in front of the fuzz, though not quite as bright. just awful sounding. i can imagine somebody buying a soul bender and thinking it was the shittiest boutique fuzz on earth...especially with all the praise it gets. anyway...it's amazing thru the vibrato channel, but i don't know what the deal is on the normal channel.

ok number two: i built a silicon fuzz face a while back and when the volume and fuzz knobs are maxed i get this very very high pitched oscillation. if i either turn the volume down to about 10 o'clock, or the fuzz down just a hair below max then everything is fine, but the crazy thing is that if i'm playing thru my deluxe reverb with the reverb on and the pedal happens to be oscillating it just completely cancels out the reverb on the amp. it's the strangest thing. i can hit a chord with the pedal on and no reverb at all...as soon as i turn the pedal off though the reverb comes crashing back in as if it had been there all along. how is the oscillation canceling out my reverb?

the two channels are out of phase with each other, i know that....is that the root of the problem? i've read about a pretty simple mod that puts them back in phase and let's you use reverb on the normal channel. would this help?

[ode2no1]

no ideas?

[newfish]

Hi - as far as your Silicon Fuzz Face goes, I'd suggest putting a small resistor (say 100 Ohms) between the 'Gain' pot and Ground.

That way, even at maxxed out, you're still within the threshold of oscillation-free living.

You're changing the taper of the pot slightly by doing this, but not by much...

[petemoore]

  To reduce gain, reduce the 1k resistance of gainpot, or introduce resistance through the AC bypass cap.

[ode2no1]

honestly i don't really feel the need to "fix" the fuzz face because turning the gain or volume down a hair fixes it right up so it isn't much of an issue, i just don't comprehend how the oscillation completely makes my amps reverb stop working. i also noticed that if i touch both transistors with my finger the oscillation problem is completely gone, but someone had mentioned to me trying to keep all the wires as short as possible, so that might be it.

[teemuk]

Ok, this is just a wild guess so take it with a grain of salt. 

The spring reverb is a transducer that vibrates (sort of like a speaker) and that vibration motivates the springs. The spring movement is then picked by another transducer that works in "reverse" converting the mechanical movement of the springs to current (think dynamic microphone).

I imagine that if you feed the first transducer with a high frequency signal the transducer will try to move between the extremes of its "travel" very fast. Problem is, I think the device simply isn't fast enough to follow the high frequency driving signal and therefore it sort of just halts. Imagine the transducer trying to move to one end of its excursion but before getting a chance to do so the drive signal already changes so that it now begins to drag the transducer to another end of the excursion. This continues on and on and as a result the transducer simply just stays still and doesn't motivate the springs at all. Because of this the guitar signal component (to which the oscillation signal component rides a top of) can't motivate the transducer either.

...I'll get my coat. 

[slacker]

That sounds good to me. I had a similar thought, that maybe the springs themselves vibrated so much at the frequency of the oscillation that the normal audio signal was swamped, your explanation sounds more likely though.

[ode2no1]

crazy. well whether or not that is correct, it's a whole lot more than i could have figured out. any ideas on why the soul bender sounds so bad thru the normal channel? it doesn't just sound "different"...it sounds nothing like it's supposed to. oh and thanks again for whipping up that layout slacker...i'm really loving that pedal.

[Boogdish]

try swapping your first two preamp tubes, if your normal channel starts sounding right with it and your reverb channel starts sounding bad then you've got a tube that's not jiving with your pedal.

[Paul Marossy]

Huh, that is a weird problem to have.