DH>If you wanted to get fancy, you could make a variable supply.  You
DH>would want one based on a regulator rather than just using a variable
DH>resistor since you do want the power supply to have as low an
DH>impedance as possible.  If you use a high impedance, the supply will
DH>"dip" every time you run a signal through it.  This -may- be musical
DH>but it doesn't sound like it would be from just thinking about it.
DH>More like the compressor from hell...
I've heard of people leaving off the cathode cap, to get compression.
(And occasionally, ear-bleeding feedback .)
And, yeah, I don't want to strangle the poor tube!  I've built
power supplies and such with 15V regulators, but I didn't know there
even was such a thing as a 45V regulator.
DH>>     This solves a problem I've been mulling over for some years.
DH>>     I built a larger experimental guitar amp with the passive tone
DH>>     controls removed.  Yet, the amp still has the tube stage that
DH>>     recovers the signal loss from the tone controls -- so the preamp
DH>>     gain was way too hot.  Without that gain stage, the gain was much
DH>>     too low, but with it the gain was too hot.  I fixed it with a 3 meg
DH>>     resistor, but it didn't sound right.  Now it's obvious that the 
hing
DH>>     to do is reduce the plate voltages drastically, so the overall gain
DH>>     is nominal but I'll get this effect you've mentioned.  Gotta try it!
DH>Actually, the gain is fixed by the components in the circuit and not
DH>the voltage supplied to the circuit.  If you reduce the voltage, you
DH>will still have the signal be too hot, it will just bottom out when it
DH>runs out of plate voltage.
Ooops....  I guess I gotta use a lower value plate resistor and lower
the gain.
DH>Check a local used book store for tube books - many times you can get
DH>Radio Amateur books from the 50's and 60's which still have lots of
DH>useful info on designing tube stages.  The holy grail is a copy of the
DH>RCA Radiotron Designers Handbook but these things are scarce!
i have a few xeroxed pages from an RCA Recieving tube manual (not  the
designers' manual).  Very valuable!
 * SLMR 2.1a *    Here at Intel, quality is Job 0.999997037582.
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