4066 switcher design issues

[Athin]

I've made a small bypass for testing based on a cd4011 and a cd4027 (schematic by Christopher Robins). I've hooked it up with the ROG English Chanell and I still get the weird noise but only when I turn the gain up - seems as though there is some feedback through the 4066.... not good. I don't think the 4066 is bad, any way to deal with this? [maybe using 2 different 4066 chips?]

[Athin]

noise problem solved (partially!) - probably grounding issue. What I did:
1) added a 22uF cap 2 ground 100R resistor in series and another cap to ground to separate the power supply of the overdrive and bypass (the one on 4011 and 4027)
2) added a 100R resistor to separate the grounds of overdrive and bypass circuit
3) connected ground of output or input jack to ground on the bypass side before the 100R resistor
4) changed hcf4066 to cd4016

I dunno about point 1, but without the changes in points 2 AND 3 AND 4 the bypass squeals/makes an alien noise. Why??
What is the difference between hcf and cd series that huh... makes the difference in this case?

[gez]

What is the difference between hcf and cd series that huh... makes the difference in this case?

Maybe the buffering of the 4066 was causing oscillation due to the extra stages within each switch (phase shifts)?

[Athin]

Don't think so gez - both had buffers [CD4016BCN and HCF4066BC]. Maybe it's the [so obvious] difference between the 4066 and 4016 rather than between cd and HCF. I'll try and get cd4066 and hcf4016 and check.
The hcf4066 might have been damaged - because some of them don't work! At all! Maybe the salesman was charged to like 100kV :shock: . But 1 out of 3 [bought 6] was OK... I think...Next time I'll use relays.
pS -> Anyone ever built a 4066-based bypass - any opinions/suggestions?