Boss CE-2 Chorus upgrade / fix

[Nuts]

Hi !
I have a Boss CE-2 Chorus pedal and it sometimes give lite overdriven notes, so can anyone tell me how to fix that ?
I also heard that it's good to replace the caps, so to which caps I need to change?
Thanks.

[Mark Hammer]

I have a Boss CE-2 Chorus pedal and it sometimes give lite overdriven notes, so can anyone tell me how to fix that ?

Yes.  Play lighter or turn the volume down.  Seriously.  The CE-2 provides no protection for excessive input signal and the delay chip can only handle what it can handle.  A little bit of compression ahead of the chorus can help to tame the peaks that produce the clipping.
Alternatively, the trimpot that sets the bias voltage which is combined with the signal must be set just right.  Too high and the delay signal distorts.  Too low and it distirts as well.  Just right and it gets clean.  It is possible that this is the source of your clipping.  One of the most common problems with pedals based around BBD chips is that the bias is off far enough that there is NO delay signal at all.

I also heard that it's good to replace the caps, so to which caps I need to change?  Thanks.

There are some caps that can be changed to different values to produce changes in the sweep speed or character of the chorus tone, but this is separate from any sort of magical upgrade of cap quality that might be reputed to improve sonic quality.  Personally, I would not expend the effort.  Delay chip-based effects are inherently noisy, limited in fidelity and bandwidth, and no cap magic will fix that.  Changes to certain values, yes.  Changes to cap type with no change in value, no.

[gez]

Hi !
I have a Boss CE-2 Chorus pedal and it sometimes give lite overdriven notes, so can anyone tell me how to fix that ?
I also heard that it's good to replace the caps, so to which caps I need to change?
Thanks.

I recently modded a delay for somebody that had the same problem.  I divided down the input signal then boosted it in the mixer stage (comes after the BBD chip, so no problems with introducing clipping).  It's probably pretty easy to do here, but a lot depends on the circuit (and PCB - sometimes you have to be a little creative how you plumb things in).  If mixing is passive, then no joy.

Post a schematic and I might be able to suggest a fix (depends how the circuit is done), but try Mark's suggestions (might only need a tweak of a trimpot) first.