I have both TeddyDAC and Altmann Attraction DAC. I used the TeddyDAC for over a year as the main DAC. Got the Altmann fairly recently.
The TeddyDAC is very good. With it albums tend to gather dust. Finally digital is getting interesting tg. Better late then never I guess. I do also have a ~ $10k LP12 setup (started with it in the mid 80's) with a $3600 Akiva MC on it the last 7-8 years or so FWIW. Use a Naim phono section wth it. It can sound very, very good.
I first tried the Altmann with a lab PSU. I knew already this lab PSU is ~ good in the grand scheme of audio things, easily besting for example a Naim Hicap when powering a Naim pre. Suspect it has a good switching PSU inside, which I think can/tends to work better in general (due to noise shifting out of the audio band basically) than simply trying to brute force filter the 120Hz ripple and such from a conventional design. And by definition, drawing energy from a PSU cap also drops it's voltage in lockstep. Anyway, was thinking I could perhaps use a quiet Teddy PSU to power it rather than a battery, having the PSU on hand already. And it was quite good that way, but wouldn't say head and shoulders better necessarily.
Then against what I thought was "educated" judgement (at the time), went ahead and bought an Optima battery and tried it. Cha-ching! Ok now we're really talking. It was a real eye opener and ty Mr Altmann for showing me the way. Now am even planning to power all my low level stuff basically with a big car battery array eventually lol
So IMO the battery supply is also quite an important aspect of the wonderfully good sound of the AMM DAC. And yes it is wonderful. Have to agree with Dick Olsher. I think it's not just because the battery is quiet (though that is super important, maybe especially so for the DAC reference). But it's also a ~ gigantic energy well basically (effecitively infinte to a small load) that can't be taxed really by the line level power device. I mean, at the risk of greatly oversimplifying, the DAC analog side can swing as hard as it wants probably and it can't really budge the huge battery supply rail. I think that likely does wonders for the analog side.
Makes me want to try powering the TeddYDAC with a battery on the analog side as well. And I would soon, but rather than hack the unit up to experiment think I'll likely instead sell it to my boss who also loves it and wants it badly. Like many lately, he uses a pc for music so it's really good for him. Me, just an old redbook CD drive is how we roll, old skule (lol) (especially when it plays this well).
And BTW the AMM DAC JISCO option does work and makes a ~ dramatic improvement, removing another veil of digital nastiness. In my mind it is very effective at helping make the drive used relatively unimportant. I'd consider it a must have option.
Back to the experiment, I now have the Wolfson factory receiver eval module and their DAC eval module. When time permits I hope to experiment with them to try and learn just how much of the AMM DAC success is the battery supply, and how much is non-os vs delta-sigma done particularly well (ie the Wilfson). In other words, try powering the Wolfson setup by big battery too and see what it can do as a delta-sigma machine with (assumed) improved digital filtering. Trying to keep an open mind here.
And hope to really deep dive and try and learn more about jitter and how to eliminate it as much as possible. The Wolfson receiver seems to have a great scheme approach to handling it and want to try and study how well it actually does at reclocking and removing the jitter from the arduous SPDIF interface journey. But getting down into the 10's of ps is vanishingly hard to measure. However, am fortunate that we have many very high dollar, high speed scopes (> 10GHz) and such at work and we might be able to do a fairly decent job of accumulating, measuring and quantifying it.
Bottom line lessons learned recently: Jitter- bad, quite audible and nasty, even relatively small amounts of it. Non-OS approach with minimal output filtering- potentially seems quite good. Battery supply- seems very good, esp when relatively huge.
Sorry for all the rambling. Thought some here could relate at least.
T
