AMB Laboratories DIY Audio

[gh0st_inthe_machine]

my latest project is a new PSU for my DAC (Audiolab MDAC), which I'd planned to use a sigma11 for the +15V digital rail and a sigma22 for the +/- 15V analog rails, both totally separate back to the mains (i.e. their own transformers)

I've just discovered that the DAC doesn't isolate the grounds between the digital and analog, so if I follow the above plan, I'm effectively connecting the ground of the two sigmas together. Would this be a problem? If so, would there be a more optimal setup?

thanks /dom

[linux-works]

if you can locate the star point where digital and analog meet at the pc board, I'd run ground wires from the s11 and s22 to the start point on the dac pcb. let them meet at the pcb and not at the s11 or s22 points.

I don't see a problem with this.

often there is a ferrite to separate digi and analog grounds, look for that on the pcb somewhere. they may have just omitted it since its not mandatory at all.

[gh0st_inthe_machine]

thanks

by the look of the schematic the grounds are bussed together immediately after the input connector (4 GND connections on its 9-pin mini-din), so I guess the only issue is whether they meet before or after the umbilical.

Now I know its not a complete clanger I'll get on with the BOM.