Back to back diodes?

[Alan W]

A friend came over last night, brought his Shnobel Daily Driver. He left it with me, and I’ll get a chance to really listen to it over the next week, but my initial impression was quite favorable. So, I‘ve been looking at the Chauffeur Driver schematic.

in several places there are pairs of diodes in series, back to back. I don’t get it. Shouldn’t this just act as a break in the circuit? Using amps as a metaphor, the headroom of my technical understanding is about on par with a tweed Champ. I’d really like to understand how this functions. It happens twice in the gain stage, and once in the power supply.

 

[spi]

Those are Zener diodes... different beasts:

from wiki: "A Zener diode is a special type of diode designed to reliably allow current to flow "backwards" (inverted polarity) when a certain set reverse voltage, known as the Zener voltage, is reached."

 

[Alan W]

Those are Zener diodes... different beasts:

from wiki: "A Zener diode is a special type of diode designed to reliably allow current to flow "backwards" (inverted polarity) when a certain set reverse voltage, known as the Zener voltage, is reached."

Thanks! That makes complete sense, and I can go back to staring at the schematic now…