Millenium Bypass Noise

[SprinkleSpraycan]

This is a weird one for me. I'm sure someone can explain it though.

I built a Catalinbread Heliotrope Bitcrusher.

Used this layout and the attached schematic.
https://dirtboxlayouts.blogspot.com/search?q=heliotrope

Predictably there was a lot of bleed thru noise in bypass from all the bits being crushed. I tried out the Millenium bypass and it worked great for blocking noise in bypass EXCEPT for the extremely loud pop when hitting the footswitch. When the effect is on the pedals after the bit crusher pop very loudly when they are turned on or off.
http://www.geofex.com/article_folders/millenium/millen.htm


How to i remedy the pop?
Why does it cause others effects to pop?

[Rob Strand]

How to i remedy the pop?

I think the root problem is C2 needs an anti-pop resistor to ground.   Add say a 2.2M from the input side of C2 to ground.

What happens is: in bypass C2 will float and discharge then when you switch in the effect C2 needs to charge up and it causes a big pop.

[Rob Strand]

FWIW, I don't get your switches.   3 pole?
The idea behind the Millenium is to use a 2-pole switch.
No need to switch power - the Millenium switches the LED.

[SprinkleSpraycan]

I think the root problem is C2 needs an anti-pop resistor to ground

good point. the layout shows the 1M to ground and is how i built it. pity that whomever drew the schematic didnt include it.

No need to switch power - the Millenium switches the LED.

true that. but if i dont disconnect power to R5 then i still get bleed thru noise. but my bad. the millinum bypass is fed constantly from 9v. R5 is the only thing being disconnected from 9v.

[duck_arse]

I look at that circuit diagram and ask myself - why is that 1M R11 shown across the volume pot - what possible purpose? is that the input pull-down resistor drawn in the wrong place, or is it actually fitted on the board in the wrong place?

[ElectricDruid]

I look at that circuit diagram and ask myself - why is that 1M R11 shown across the volume pot - what possible purpose? is that the input pull-down resistor drawn in the wrong place, or is it actually fitted on the board in the wrong place?

+1 agree. Looks like a board tracing error to me. Should have been on the other end!