Battery PS for y2 DAC?

[ptempel]

I'm thinking of building the y2 (gamma 2) DAC:

The γ2 Compact High Performance DAC

For the PS, I was thinking of using a 9v SLA battery with 5v regulator. Can I use the s25 (sigma 25) and swap out the 7805 regulator with an LDO? In the s25 schematic on this page:

The σ25 Regulated Power Supply

was thinking of replacing:

- 7085 with LM2940
- C3 with 0.47uF cap
- C4 with 22uF cap

and removing:

- D1 bridge rectifier (bridge pins 1 & 2 and 3 & 4)
- C1 and C2 caps

I got the C3 and C4 values from the LM2940 datasheet. Does this look correct? Also would be cool to add a battery checker circuit like the one one the DDDac website. Would that be as simple as connecting it to AC IN?

Thanks,
Philippe