Sea Urchin Mix problems

[claytushaywood]

I have built the Sea Urchin
It's working completely fine except for one thing.
No Mods

My Mix pot is performing strangely (at least I think it is).  When turned all the way down, the repeats are still pretty darn loud... like not close to being subtle.  the mix knob does work... it's just the opposite of sensitive.  at maximum it does give me a first repeat above unity gain, which is nice... but maybe not correct for this circuit?

I've tried taking the pot out of the circuit and testing it. and it seems perfectly fine.  I've checked the resistors around the mix pot but they seem to be right on, in circuit at least.  I've tested all my connections and they seem to be just fine.  Maybe I messed up a resistor somewhere.

Anyways, would the 20k R17 be something to lower or raise to try to get these repeats quieter?  Or maybe the 2k R16?

Can anyone tell me what component(s) are responsible for the mix volume? (besides the pot) I guess I could have screwed up on my check of that as well. 

Any insight is always greatly appreciated!

[claytushaywood]

Is there any reason that I'm not getting any replies?  I checked out the rules... I seem to be following them, maybe i'm not??
Things I did to try to fix it--- a lot... checked what I thought to be relative component values, undid a few mods I had installed (Repeat darkness switch, overall output knob, momentary infinite repeats)  I undid all those, replaced a few suspect capacitors, desoldered the mix pot to check it... It does actually go up to 60k- forgot to mention that... could that be the problem?

[jkokura]

Part of the issue may be that the Sea Urchin is an extra project, and since it's not a sold project not a lot of us have much experience with it.

Based on the schem, it's pretty much like all other PT2399 type delays for the mix knob. At minimum, you should be getting no repeats at all. That indicates that something is wrong with your circuit, but it'll be hard to determine what. The pedal is functioning correctly otherwise right?

The Mix pot in this instance is merely a variable resistor. At full resistance, no delay signal would be getting through to the output buffer. At minimum resistance, you would be getting delay signal louder than your dry signal. I'd suspect either a solder bridge, incorrect wiring, or a bad pot.

Have you got another pot?

Jacob

[gtr2]

The forums usually slow on the weekends.  I've built a few sea urchins.  You shouldn't have to adjust the R17 20k resistor.  Although it would help the mix issue, the stock value is fine.  I've built both the etched version and a personal fabbed version.  I remember troubleshooting my etched version.  I ended up having a very small solder bridge.  I'm not saying that's the problem but it is very easy to have bridges on this build.  Mine happened to be at one of the potentiometers because I couldn't see that the solder wicked behind the the pcb mounted lugs on to another pad.

Josh