convert aleph 2 to pre for f4

hi
i have just about finnished building 2 x f4 clones to replace my aleph 2 clones
my question is can the aleph 2 be modified and converted to a pre amp with a volume control added to power my f4

the a2 monos cost a lot to build and it would be a shame to see them not used ,it would be great to convert them into a pre amp with just enough gain and output to drive the 2 f4 clones (daul mono aleph 2 preamp driving 2x bridged stereo f4 cones = heaven hopefully)

the a2 is all standard exept it is run on 25v secondary,s instead of 38v i could drop the supply voltage and lower the amount of output devices no probs but what else would be required to make this work

cheers
 

Melon Head

Banned
2006-11-10 10:14 am
Since you already have the transformers you may as well use them.
However you could try a shunt regulator.
You could also replace the input devices with 2 x 2sj74.
I would do these things in steps rather than try them all at once.

It might not be necessay but I would be tempted to put a 10uF cap on the output for safety. It is very important to get the dc offset as close to zero as possible if you are not going to use a cap at the output - I don't think the F4 has an input cap.
 
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