diode warp?

[Br4d13y]

i saw something about it somewhere(can't remember), a diode warp control,  but i don't know what it does, help?

[John Lyons]

Sometimes called a "Warp" control Look for this over at AMZ (link above).
Fancy name but it's just resistance between the diodes and ground for a diode to ground clipping circuit.
This raises the threshold of the diodes making them clip less or more depending on the resistance between them and ground.

john

[caress]

i think john forgot the link:  http://www.muzique.com/lab/warp.htm

[R.G.]

A resistor is linear - the current resulting from a changing voltage is always proportional to the voltage change.

Diodes clip because their voltage versus current curve is nonlinear. You can increase the voltage across a diode and the current increases almost not at all until you read the diode's forward voltage, then it increases dramatically at that point.

"Warp controls" is a way to say that putting a resistor in series with a clipping diode adds back in some linearity to the diode clipping. Voltage across a resistor+diode increases with no current flow until the diode's threshold is reached, then the diode lets as much current flow as will flow. The resistor however, causes a voltage proportional to the current flow added on top of the diode's voltage. So the diode cannot clip as solidly as it might have, the resistor adds some of the signal voltage back in. You can obviously do this with a different resistor in series with each diode of a clipping pair, hence the "warp" (as in twist) nomenclature, presumably.

Every diode clipper can be thought of as a resistor plus diode. For resistances under about 10 ohms, it's very hard to tell that from zero resistance. For resistances approaching the impedance feeding the diodes, the diode clipping almost vanishes. In the most common diodes-to-ground clippers, the diodes are fed through a resistor of about 10K, so adding resistors under 10K is called for.

[Br4d13y]

thanks, will have to try it out

[snap]

John did not forget anything:
right beneath the white/blue logo of this page there is a list of 12 links,
the last of whom is labelled: " |AMZ| "

"link above"

by clicking that link and scrolling down that upcoming page a bit,
there`s a search field which can be used to search for e.g.: "warp".

guess what will happen?

[caress]

whoops.  never saw that link...