F4 power amplifier

Sorry I misread the answer. Why not use balanced to balanced, when you have the posibility ?

Yeah of course that would certainly be an option but would require 4 channels, so double the components, I'm not sure whether everyone would want to do that, but it is certainly worthwhile and a better alternative to adding extra gain stages imo.
 
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No I dont talk about bridged F-4´s, just normal balanced inputs.

That only needs one BA-2, which has balanced inputs and one F-4.
You would need a transformer or differential input to convert balanced to single ended.
You can't do balanced to balanced without using 2 F4 channels (ie 4 for stereo).

I think if you converted the input of F4 to a push-pull double differential buffer you could make it work. Could be wrong, have to think about it.
 
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Please read up on the BA-2 input stage, which has 2 balanced inputs. It converts the balanced signal to single ended internally which is sent to the F-4 input.

You simply connect 2 balanced XLR cables from the preamp to the F-4 (with a BA-2 input stage). The preamp has both balanced inputs and outputs, so he will also have the possibility to run his comming DAC balanced in.
 
Please read up on the BA-2 input stage, which has 2 balanced inputs. It converts the balanced signal to single ended internally which is sent to the F-4 input.

You simply connect 2 balanced XLR cables from the preamp to the F-4 (with a BA-2 input stage). The preamp has both balanced inputs and outputs, so he will also have the possibility to run his comming DAC balanced in.
Sorry, had a brainfart, I was thinking you had a Balanced BA3 front end.
However adding BA2 is adding extra gain stages between his preamp.
He would be better off doing Balanced F4 direct from his preamp or if his preamp has onboard balanced to single ended conversion to use it.
 
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97.3% of all poweramps has a VAS Voltage Amplification Stage, i dont see the problem.

The case is I have sold 2 F-4 kits with BA-2 stages, because I didnt had the energy to assemble them myself.

The first guy chose not to build the BA-2 and never got satiesfied with the result, I dont want that to happen again.

Best regards
Arthur.
 
97.3% of all poweramps has a VAS Voltage Amplification Stage, i dont see the problem.

The case is I have sold 2 F-4 kits with BA-2 stages, because I didnt had the energy to assemble them myself.

The first guy chose not to build the BA-2 and never got satiesfied with the result, I dont want that to happen again.

Best regards
Arthur.

Nothing at all wrong with doing that. I am anal perfectionist.
My definition of perfection, is Less is More, I've come to agree with Nelson ideas, and now I am solidly converted.
 
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All of his amps but F-4 has a VAS so far I know.

You haven't quite understood the master's teaching yet.

If he does balanced F4 he gets 16V rms from his preamp without the need for extra gain stages.
16V rms is enough to clip a single ended F4 but that also requires extra gain stages to do it.
Balanced F4 is a more Zen solution to his specific situation.
 
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Could someone point me to the latest version of the crippled F4?

And should I change any part values if increasing the psu rails to +-32V?

So I finally found the info regarding the crippling of the F4. There was some information regarding leaving out the the output capacitor on the BA3FE since there are the 2 220uf caps on the input of the f4.

Couldn't I remove those instead and keep the output cap on the BA3FE and get the same result?

Still can't find any info on changes for higher psu rail voltage though.