will this work

[rtill]

just curious if this would work

[Tube_Dude]

Originally posted by rtill
just curious if this would work

Yes!

[pacificblue]

Second schematic. See also the updated version P3A.

[AndrewT]

The Vbe multiplier is ineffective due to the limiting effect of the two series diodes.
That 1.2V to 1.3 volts will probably bias the amp into ClassB

Do not put the wiper of the vbe multipler to the base of the transistor. If the wiper goes open circuit it can lead to a blown output stage and that in turn could blow your speaker.

One pair of robust output devices can give 100W into 8r0 using ~+_50Vdc.
But to get 100W from the +-42Vdc requires one to use 4r0. This is asking too much from one pair of small output devices.

[rtill]

I was planning on using 4 ohm speakers.

[darian]

Just buy an AKSA amp. That is what your schematic is (except the 2 useless diodes). This type of topology has been working for years and will be working forever.

Where have you been? LOL

[thunderpld]

Could use a current source.

[lineup]

Originally posted by AndrewT

One pair of robust output devices can give 100W into 8r0 using ~+_50Vdc.
But to get 100W from the +-42Vdc requires one to use 4r0. This is asking too much from one pair of small output devices.

42 Volt rails.
50 Watt into 8 Ohm, yes.
For 100 Watt at least 45 and probably like AndrewT suggest 50 Volt
(40x40) / (2x8) = 100 Watt into 8 Ohm
where 40 is the peak voltage from supply.

Your drawn amplifier will work even if it is very basic.
There is nothing wrong with your circuit in schematic.

[AndrewT]

but extracting 100W into 4ohms is more onerous than 100W into 8ohms.
One pair will struggle to deliver into a 4ohm load.

[ostripper]

Just buy an AKSA amp

AKSA is $$$$.. I think trill wants something economical.
DX amp with 2 pair OP devices or my Frugalamp 1 would
do 4 ohms nice..
Or Quasi NMOS.. all these amps have support, PCB work
and cost 25-50$ (not including power supply) as well
as using very common devices..

OS