Stupid M3 questions which I'm sure have been answered before...

[Pars]

The mosfet power is not symetrical, V- is ground. Am I wrong about this ?

Last project I did was stupidly populating a printed PCB (dynalo). I learnt lots about how the amp works but nothing about layout.

V- in the case of the M3 (and many other virtual ground amplifiers) depends upon your perspective, but is actually the - of the single ended power supply. It functions on this schematic as the - rail, (or V-). Ground reference is generated by a TLE2426 and is 1/2 the potential of V+ and V-. So for example if you are using a 24Vdc power supply, if you measure V- in relation to the - lead of the PSU, you would get 0V. However, if you measure it in relation to the virtual ground (SG on the schematic), you will see -12Vdc for V- (and +12Vdc for V+).

[Bidoux]

I think I got it. Thanks everyone it was really kind to answer me.

[Looser101]

I think you need to understand how virtual grounds work. It will make your life easier.

Virtual Ground Circuits

[Bidoux]

I knew the TLE2426 was acting as a ray splitter but I didn't totally understood the first power supply. I do know.

[MASantos]

This is a question that just crossed my mind:

Would there be any advantage in powering an M3 with a o22 bypassing the railsplitter instead of just using a o11?