Grounding of constant current sources

[angelo66]

Hi all,
I would like to have your suggestions about the correct grounding of constant current sources of IPS e VAS, in a conventional class AB amplifier.
Please see the circuit attached.
Where would you connect the red-highlighted grounds? To the signal ground or to power ground?

Thanks!
Angelo

 

[dl3it]

I connect them to power ground. The "constant" current is not affected by this, as it is regulated by the control loop of the two transistors. The ground connection gives some kind of bootstrap...
Further, I always try to reduce the current flow on the signal ground as much as I can to keep signal ground clean.

 

[angelo66]

Thank you very much!