• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Output penthode with MOSFET driver

Link doesn't open.
I see, it is 3 gain stages and eventually no op-amps and another psu for them.

This only brings me to other questions... :
Tube stage -> MOSFET buffer -> tone stack -> MOSFET buffer -> send return -> tube stage (OR LND150)-> MOSFET PI -> power tubes.
Avoiding op-amps and auxiliary psu.

Otherwise I have other considerations for the preamp part.
F.ex. swapping the preamp modules and have 4 triode gain stages, OR penthode + double triode (I built that once on flying boards and it was nice).

In general the chassis is going to be universal (options for swapping pre and power amp boards), I am not going to build numerous amps for all of them 😄
 
If it is to avoid op-amps and auxiliary psu, cold the following tone stack go in this order:
Screenshot_20241227-192725~2.pngIMG_20241217_233024_469_LL~3.jpg
And somehow the same MOSFET buffer after the tone stack
Screenshot_20241227-192725~3.png

I don't know how exactly to put up the output buffer
 
This is the schematic from an EQ kit...
IMG_20241217_233024_469_LL.jpg
I ...can't calculate right away if the bipolar transistors have some gain, but I suspect so for the EQ to work.
So, if the first transistor is the MOSFET follies tube-out buffer, the output transistor might need to be lnd150 ?

What if the tone stack is after the fx loop:
- fx return -> lnd150 pre -> tone stack -> MOSFET PI -> power tubes

I looked up some all tube amp schematic with a tone stack and fx loop (some ENGL stuff) and there are triodes enclosing those nodes, resulting in many tubes..
That's why I went for a solid state and separate psu.
Doing it no-tube on high voltage seems trouble.

Leaving the bold experiment part "just" to drive the output penthode solid state + high voltage.
And also having a back-up solution, the output tube to be triode-penthode, in case the solid state experiment fails 😄😄
 
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