All JFET PLH Amplifier

Melon Head

2006-11-10 10:14 am
I have been thinking what I should build with these Semisouth power JFETs.

I have narrowed it down to Aleph J, Aleph 30, or PLH.

However I have decided I want to try the PLH mainly because I already have a JLH and I would like to compare the two (I already have an Aleph J and 30 so I can easily modify them at a later stage).
The second reason is, that I would like to try replacing IRF610 with lu1014d.

I am thinking of something like a simplified F3 first stage connected to semisouth SJEP120R100 at output.

The other options are all semisouth 1st stage and 2nd stage either All SJEP120R100, or SJDP120R085 at input and SJEP120R100 at output.
If I choose this option I will probably need to use an input buffer, but maybe not.

The other option is parralleled 2sk147 or 2sk369 at input connected to SJEP120R100.

At this point in time I am tending towards using lu1014d at the input (mainly because I already have quite a few of them). I will probably use or at least try an Aleph current source mainly because I have not seen anyone use it on the driver stage of an amp and I want to compare it to a regular current source.
I am not sure if a modulated cascode will bring any benefits here or whether I should just use a regular cascode.

I will try to post a few simplified schematics when I have a chance.
However if you guys have ideas feel free to post them.