[Patrick Turner]

Prune wrote:

Thanks, I guess that answers that question. Now if I could only find
curves for the MOSFET. The datasheet only has current vs voltage ones.

But what current and what voltage at what electrodes?

Mosfet data should appear like pentode data, ie with Id plotted on a
vertical
scale and Ed horizontally, and the curves you see are Rd curves at
various values
of Egate.

But you have a PP circuit, and wishing for complementary oddorder
distortion cancelling is rather like like
wishing santa make a special trip in July.

Just remember that a +1V applied at the cathode gives +20V at the anode;
the tube becomes a non-inverting amplifier.

One way is to fire it up and start fiddling with bias currents,
but without tempting smoke, and see what your THD meter tells you.

If I attempted direct drive of ESL panels I'd use a far simpler
amp circuit without any SS within, except perhaps for a CCS load in an
input LTP stage.

Good Luck,

Patrick Turner.


Patrick Turner wrote in news:4608C3FE.2DCAD8A1
@turneraudio.com.au:



Prune wrote:

Hello gentlemen,

I've not been able to find EL34 curves for cathode-driven operation
anywhere. Help would be greatly appreciated!


The grounded grid curves are the same as for grounded cathode in either
pentode, UL or triode.

Voltage gains are indentical.

All that changes is the input impedance which is high for grounded
cathode, and very low for
grounded grid, and Rk in = RL / voltage gain.

There are no separtae groups of curves for grounded grid.

Musicman guitar amps used transistors to drive the cathodes of output
tubes,
and this could have been a reason why they went out of business.

Patrick Turner.