SOLVED Cepheid Chorus problems

[squirrelboy]

Hi everyone,

I was a little hesitant to post this considering how much of everyone’s time I’ve taken on my other post about my XC Phase, but here I am again. I just finished a Cepheid Chorus build and it doesn’t seem to be working correctly. Even with the rate turned all the way down, the LFO led blinks extremely rapidly. Also, when the effect is on there is a massive volume drop, and the effect sounds more like vibrato than chorus.

I am using the V3207D and V3102D chips which I purchased from StompBoxParts.

Here are some pictures. I have a sound clip I recorded using the voice memo app, but I can’t figure out how to post it. I will follow up later with a sound clip.

My plan is to check the VRefs when I get home, but I would appreciate any ideas on what might be going on here.

Thanks!!

 

[Bio77]

Post the voltages for the TL022 and the 4558. Your LFO problem aside, sounds like the delay line is working and you don't have any clean signal. Try audio probing R34 to confirm.

 

[Locrian99]

Does your rate pot affect the rate of the led blinking.

Have you tried fine tuning your trim pot to see if that affects the volume level. I’m assuming it sounds more like a vibrato because it is moving quickly though I suppose you could have lost your dry signal and you’re only hearing the wet.

 

[synthesiserror]

R6 is a 10k but needs to be a 1M. Looks like you made the same substitution with R1 and R33, as well.

 

[squirrelboy]

R6 is a 10k but needs to be a 1M. Looks like you made the same substitution with R1 and R33, as well.

Oh my gosh you’re right!! I wonder if I made the same mistake on my XC phase!!

Thanks so much for pointing this out! I can’t wait to get home to try to fix it.

 

[synthesiserror]

Oh my gosh you’re right!! I wonder if I made the same mistake on my XC phase!!

Thanks so much for pointing this out! I can’t wait to get home to try to fix it.

I haven't taken a look at the other thread yet, but I'd check any resistors that are supposed to be 1M on that board and in your parts bin. Mix-ups happen, and sometimes orders get filled wrong.

 

[squirrelboy]

IT WORKS!!!! THANK YOU!!!!