4016, switching audio and VCO signals

[Tony Allgood]

Hi,

I would not want to pass the final mix out through one, or a 4066
directly. Why?
1. Distortion is too high
2. Limited output swing +7V5 to -7V5 is your max. This will also make
your control signal rather tricky. You could bias the audio up to half
of 15V before switching.
3. You have to use two. One series pass, the other shunt. NOT control
required.
4. They do thump a bit, you will hear it.
5. Some better parts exist. SSM used to do a click less audio one. I do
not know whether they still do. The DG2xx series are quite good, but
again should be used with an op-amp. DBX vca's are good too, but pricey.
6. Op amp and two fets are better. No click. Controlled on times. And
less bleedthrough. If used near the virtual earth they are switching
current not voltage (except for Rds on), output swing limited by the
op-amp.

If anyone needs the circuit for this, mail me and I will do a copy in a
few days. I don't feel up to ascii drawing at the moment. My baby
daughter's teeth are deciding to come down today.

However, for switching VCO outputs & inputs, etc the 4016/66 is fine.

Regards,

Tony Allgood, Cumbria, UK

e-mail: oakley at techrepairs.freeserve.co.uk

Rack mounted Moog VCF module. Details to be found at...

http://aupe.phys.andrews.edu/diy_archive/schematics/effects/filter.html



All,

Has anyone used these 4016 Quad Bi-Lateral Switches. I'd like to know if
they are okay to switch audio, (the fact sheet on them says they will),
but
I'd rather hear it coming from someone who has used them. I'm looking at
using them to construct complex oscillator shapes by switching voltages
clocked via a counter. Could they be used in a MIDI controlled audio
patch
bay, or is the audio response poor if I were to switch CD quality audio
signals through them.



Mark.