[denjo]

Hi
Owners of the Altmann Attraction DAC (and owners to be) might be interested in my venture to find a power supply other than a SLA. The creator Charles Altmann recommends the Optima RedTop as the ideal source of power or any other SLA battery as second best. I had Vinnie's RWA battery (10 Ah) for a blissful short while before the battery died on me. Sourcing for a Redtop in my locality is well nigh impossible - no dealers or agents carry such exotic SLA batteries! During the short time I had the battery, I enjoyed the Altmann but observed that: (1) when the battery voltage dips below 12 v, performance suffers! (2) even with the battery properly charged, I sometimes wonder what the effect of voltage swings might have on the DAC (3) the thought of storing a SLA battery made me nervous and paranoid about its inherent hazards (fire, shorting, noxious fume emission).
This got me thinking: is it possible to fabricate a power supply that will supply a steady 12 v and is largely immune to voltage dips? Linear power supplies have been used with great effect on several audio gear, enhancing the sonic performance of whatever equipment it supplies. Then, there is also another type of power supply which I understand is even better, called a shunt regulator. While I am no electronics engineer or expert, its seems to me at least that a power supply that can provide clean power, and is immune to load (within reason) must surely translate to an audio gear that it powers performing better than a wall wart supply. Could it also be able to provide such clean power that it can compare favourably with a SLA battery?
I will be sourcing for an audio engineer who can build me a shunt regulated power supply that will be overengineered, able to manage and handle extreme loads and yet is stable. Arguably, if such a power supply can be fabricated without breaking the bank, I would be interested to share my views of how the Altmann (and for that matter any other audio equipment like the SB3) will perform with such an alternative source of power. Stay tuned, this project will come to pass in the months ahead!
Meanwhile, I would be happy to hear views from fellow members of the wisdom of such an endeavour.

Best Regards
Dennis

[miklorsmith]

Hmmm . . . you may want to post this over in The Lab.

Rather than building one, you may be able to buy an industrial unit on e-bay for pretty cheap.

Your 10 Ah battery should be good for about 20 hours of play time.  My 12 Ah unit was good for 24.

[denjo]

Industrial, No! Medical, maybe! Let's see ...

[mgalusha]

Mike's Altmann should arrive on Friday. Wayne from Bolder cable as offered to lend me a 12V version of his power supply to see how it compares with to a battery. I was going to PM Mike to see if he was OK with this but seeing this reminded me.

Mike, any objections to trying the Altmann with a 12V linear PS as well as the battery?

Mike

[miklorsmith]

If Wayne built it, I'd say no sweat.  Actually, that's a great idea.  If anybody on the tour has a chance to try out a car battery, esp. the Red Top, it would be really great to get that comparison too.  Charles says he's only tried the Red Top and that other batteries will sound different.