230v psu

[Strikkflypilot]

Hi!
Anyone have a good advice regarding a good 230v to 9v psu for the Bottlehead DAC?

[mcandmar]

Disclaimer first, use of anything other than what BH supplies isn't supported, and if you fry something that is certainly not going to be covered under warranty.  I don't even know if BH have a stock of spare boards so you run the risk of turning it into an expensive paperweight.

That said you need something in the 6-9volt range that can supply a constant 500ma.  Somebody posted recently about a 9v supply they bought, but it wasn't cheap.

[Strikkflypilot]

Thanks for the disclaimer.
I saw the Teddy9/2 PSU, costs more than a Crack, though.
It is necessary to know the dimensions of the 9v plug, though.

[mcandmar]

True. I am sure there are other supplies out there for reasonable money.

Socket is a regular barrel connector, 5.5mm outer, 2.1mm inner, center positive.

[Strikkflypilot]

Thanks.
Anyone thinks I would risk too much with this, please chime in:)

[ToolGuyFred]

You could try what I did and run from 8 AA alkaline cells. They get hot and only last a few hours but convinced me batteries were the way to go.

The 230 to 110V adaptor which came with my DAC kept tripping out so I bought a bigger unit from Maplin electronics. When the BottleBat came out, I was tempted but this would have meant a 4-box solution for a DAC!

I built a PSU based on Yuasa emergency lighting cells (8 off 4AH D-cell NiCad). These have a low internal resistance and unlike lead acid types can be run completely flat without harm. I get 8 hours listening per charge and have the cells breadboarded with their own periodic current reversal charger. (Charging NiCads the usual way from a constant current source isn't recommended but I have cells 20 years old and as good as new which have  only been subjected to PCR.) Recharging takes 16 hours. A relay on the charge circuit disconnects the output while charging. I now have no means of running the DAC from the mains but you soon get used to flipping into charge mode when not listening.

If you go for mains power then I'd suggest building your own 9v unit with shunt regulation as I haven't found anything out there HiFi enough for the job...

[Bacci]

I would just build a high quality linear power supply, like this one for example http://www.amb.org/audio/sigma11/.
Should also be an upgrade in theory, although the filtering in Bottlehead's DAC is already so good you'd probably not be able to A/B it