Some questions
 

Hi,

* I like to use may be switching psu with 24V.
As there are no +/- 24 available I like to connect two supplies in series and connect the middle pint to ground of preamp or whatever.

There may be some disadvantages (?)
But there are maybe less problems with 50Hz ripple ?
And much better eficiency and not so heavy.

* Are distortions random signals ?
If yes, will distortion be reduced by paralleling Fets ?
Noise will.

* In the below circuit, Nelson stated that switching of Diodes D11-14 might be a problem...
Does bypassing with small caps help ?



Greetings, Bernhard






http://www.beautyphoto.de/atlantis.jpg

Looks like you have the basic idea right.

Schottky diodes minimize the noise, an RC snubber may not even be needed.

http://164.195.100.11/netacgi/nph-Pa...&RS=PN/6304138

Click on 'images', you need a TIFF viewer (free).

As you can see from fig.5 you only need one diode, not four, and only one (big) transistor on the top voltage tier.

An ordinary center-tapped transformer will provide the voltage tiers required.