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zener diode bounding circuits
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I'd like to know more about the variations of the zener diode bounding circuits that are peppered throughout TUT and seen in some popular modded-Marshall preamp designs (Jose/Cameron/Friedman/Fortin). Here are some specific questions for starters:

1. Sometimes there is a 10k resistor (and large-value coupling cap) off of the cathode follower. Why is this used, and what are the drawbacks of adding it?
2. Some incarnations of the circuit replace the usual large-value coupling cap with a 100n cap as part of the shunt circuit (that is, in series with the compliance resistor and zeners). I get that this cap would keep DC off of the zeners, but I'm not sure how the value of the cap would be chosen. 
3. Some of the modded-Marshall designs listed above put the Master volume immediately after the clipping circuit and before the tone stack. Others put the Master after the tone stack but put a 1M resistor in parallel with the zeners (or in this specific case, transistors). What is the rationale behind this load?

I could draw out some schematics tomorrow if need be.
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Messages In This Thread
zener diode bounding circuits - by jmcd - 11-08-2018, 02:18 AM
RE: zener diode bounding circuits - by K O'Connor - 11-08-2018, 02:41 AM
RE: zener diode bounding circuits - by jmcd - 11-09-2018, 12:33 AM
RE: zener diode bounding circuits - by K O'Connor - 11-09-2018, 12:46 AM

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