# [SOLVED] Caesar Chorus High pitch Noise problem!



## d.d.sound (Mar 19, 2022)

Hi! I'm new to this forum! I have a problem with the Caesar Chorus I built. When I turn up the Lag potentiometer, a high pitched noise appears. Synchronized with the Rate pot. 
What could be the problem? Can someone help me? I used the "mn" integrated instead of the Cool Audio "v". I don't know if this could affect it. Thanks in advance!
D.

View attachment 24190View attachment 24191


----------



## music6000 (Mar 19, 2022)

d.d.sound said:


> Hi! I'm new to this forum! I have a problem with the Caesar Chorus I built. When I turn up the Lag potentiometer, a high pitched noise appears. Synchronized with the Rate pot.
> What could be the problem? Can someone help me? I used the "mn" integrated instead of the Cool Audio "v". I don't know if this could affect it. Thanks in advance!
> D.
> 
> View attachment 24190View attachment 24191


Did you use a Plastic Dust Cover on your Blend pot???


----------



## d.d.sound (Mar 19, 2022)

no, I used the normal potentiometers without a plastic cover. Where could I find them online? 
Thanks!


----------



## music6000 (Mar 19, 2022)

Is it in the Enclosure???


----------



## mybud (Mar 19, 2022)

First see if you can insulate the pot from the board with a piece of non-conductive material. (Tayda supplies pot dust covers for future reference). See if that eliminates the clock noise (surmising here). Have you tried tweaking the trimpot a bit? There may be an optimal setting where you get the chorus effect but minimal noise. Perhaps try the tweak with the lag pot producing the noise and see adjusting if the trimmer affects this. This board is next on my never ending list of PPCB orders. Will be keen to know how you get on.


----------



## d.d.sound (Mar 19, 2022)

yes, the pedal is closed in its box. I found a plastic cover from an old pot and put it on. No results, still noise. Even acting on the trimmer, nothing changes.


----------



## mybud (Mar 19, 2022)

Have a look at the generic troubleshooting guide maybe. Next step would be to provide pics of both sides of the board. There may be an incorrect component value somewhere. Then measure voltages with a DMM and provide these if possible.


----------



## fig (Mar 19, 2022)

C2, C20 are 1uF and C11 47pF ?


----------



## d.d.sound (Mar 19, 2022)

I have checked the component values several times and they all seem right to me. In any case, here are some photos ...


----------



## fig (Mar 19, 2022)

Well it certainly looks nice. There are folks with way more experience than me, so I'll not get in the way. Hope you get it sorted quickly!


----------



## mybud (Mar 19, 2022)

fig said:


> Well it certainly looks nice. There are folks with way more experience than me, so I'll not get in the way. Hope you get it sorted quickly!


Yes indeed, @fig. My suggestions are based on what I’ve been reading up on regarding BBDs and the so-called ‘clock whine’ issues associated with them. I’m waiting for my five pairs of 3102/3207s to reach here and will order the Caesar boards once I’ve checked them (the chips) to see if they are ok. So I’ll gladly defer to folks who have actually built the board successfully


----------



## szukalski (Mar 19, 2022)

Is the pedal grounded to the enclosure. I had a similar grounding issue.


----------



## music6000 (Mar 19, 2022)

d.d.sound said:


> I have checked the component values several times and they all seem right to me. In any case, here are some photos ...





d.d.sound said:


> I have checked the component values several times and they all seem right to me. In any case, here are some photos ...


Can you confirm your Trimmer is a 50K???
I hope your BBD chips are legit???


----------



## d.d.sound (Mar 22, 2022)

Good news!!! Checking the components for the third or fourth time I realized that I have put c11 of the wrong value!
470pF instead of 47 pF! 
Thanks to everyone for the advice! Good advice is always needed!


----------



## mybud (Mar 22, 2022)

That is very good news. Glad it has worked out and itching to know how it sounds to you


----------



## andare (Mar 22, 2022)

d.d.sound said:


> Good news!!! Checking the components for the third or fourth time I realized that I have put c11 of the wrong value!
> 470pF instead of 47 pF!
> Thanks to everyone for the advice! Good advice is always needed!


Good news! That's why I quintuple check every value before soldering.


----------



## d.d.sound (Mar 24, 2022)

The pedal sounds really good! A modern chorus that lends itself well to various styles!


----------



## szukalski (Mar 24, 2022)

It's a keeper, so flexible!


----------



## mybud (Mar 24, 2022)

Thanks for the info and again glad it worked out for you. On my next order for sure ... 


d.d.sound said:


> The pedal sounds really good! A modern chorus that lends itself well to various styles!


----------



## mybud (Mar 25, 2022)

So, this is great timing for a 15% off PPCB opportunity too good to miss. I ordered one each Caesar and Cepheid PCBs. Just waiting for the BBD chips to arrive, which could take awhile but hell, Patience is my middle name after all. Thanks for all the feedback on the Caesar (pun intended).


----------

