Build Your Own Clone Message Board

I just finished a new Crown Jewel build with the Dry Blend board. I have built Crown Jewels before, but this is the first time with a Dry Blend.

I am comparing it to my old Crown Jewel build (no Dry Blend) and there is a VERY big difference in loudness.


With all other settings the same, the old build (no dry blend) needs the Level knob at 2pm to be in the same ballpark loudness as the new build (with dry blend) with its Level knob at 9am. I can't imagine this is due tolerance differences of the components.

Is this supposed to be the case? Does the "Dry Blend" board make the Crown Jewel greatly louder overall (because of how it uses the charge pump or something)?

I compared the two Crown Jewels again today and the loudness differences were still there, but not as drastic.
The older Crown Jewel (no dry blend) with Level at noon has about the same loudness as new Crown Jewel (with dry blend) with Level at 9:30am.
(This is with the dry blend at max, and all other switches and knob positions at about the same.)

Weirdly, there is now a loud, steady whistling noise when I turn on the boost (LPB-1) of the older Crown Jewel (no dry blend)! I built this pedal years ago and it has never done this before. I'm also noticing it has a bit more background hiss when the drive side is activated. FWIW the whistle noise changes to a lower pitch when I switch to 9V.

For troubleshooting, I tried these things:

• I switched LPB-1 modules and the older Crown Jewel was still making the whistling noise with the boost turned on.
• I switched charge pump IC's and thought this fixed it, but then the whistling started happening again (still constant & similar pitch, but not as loud).
• I switched from an isolated power supply (whistle happened on different ports & cables) to a 1-spot and now there's a buzzing instead of a whistle when activating the boost.

None of these things effect the loudness difference, FWIW.

Does anyone have an idea what this whistling problem is when activating the boost? (Some grounding issue?)
Is whatever is causing the whistle maybe related to the loudness differences between the pedals? Or are these unrelated issues?

in my experience, that high whistle is a charge pump issue. I know you replaced it, but what model did you use? I've gotten rid of the whistle in the past by using the chip that ends with an SCMP, if memory serves.

_________________