I've owned the Altmann DAC for almost 2 years now and decided that this product is so special that it deserves a review. Prior to moving toward a computer-based system, I owned a Naim CDS-3, a very good player that I sold for $7,500, just to give you an idea of price point.

When I first got the Altmann, I had some trouble getting it to sound right. I was new to the computer audiophile world and I was new to optical cables. After several exchanges with Charles Altmann, whose customer service is exemplary even across the ocean, he convinced me that with the JISCO circuit, the cheapest plastic optical cable would sound as good as anything higher priced. Good. Why spend the extra money if I didn't have to? I soon discovered that the problem was in iTunes. There's an internal equalizer that was set for optimizing the cheap internal speakers. I switched it off; problem solved.

The bottom line is that, shockingly, it kicked the butt of the Naim. The natural tonality is key. All those other audiophile goodies like sound-staging, transparency, PRaT, etc. are worthless without natural tone. That's not to say that the Altmann lacks the other stuff, but it's ultimately the tonality that makes it all sound like music.

I have gone through three major upgrades in my system since I got the Altmann. In each case, I was concerned that I'd be revealing its limitations. In each case, my concerns proved unwarranted. Seems like there's just pure, beautiful music waiting to be uncovered downstream.

This is an anti-elitist DAC for the rest of us. It's Dom Pergnon on a beer budget.

System: Equitech 2Q Balanced Power unit; Drobo hard drive storage; Mac Mini running iTunes; Ars-Sonum Filarmonia integrated tube amp; Merlin VSM-MMe's with Master BAM. Cardas GR interconnects; Audience AU24e speaker cable.

Analog like sound
PRAT
No fatigue
Musical
Enjoyable, can listen for hours
Make your CD's sound as close to Vinyl as possible with PCM

The physical appearance of this DAC needs to improve, but the designer says, this is the key to it's musicality. I'll take the music !
Battery powered from a car battery, but slightly inconvenient. But the sound, is just superb.

Ok this is one usual product. It's just a PCB attached to a piece of wood. No power supply either, you have to run this from a car battery. Now before you freak out, let's explain the technology and then get to the sound. Ah - you want to the sound first ? OK folks - let's go down to business : THIS DAC IS THE BUSINESS ! It is non-fatiguing, you can listen to CD for hours, with or without a tube amp. This DAC will make your CD sound analogue and similar to Vinyl. And last but not least, you will ENJOY music through this DAC. Which was the point all along wasn't it? OK now the technology. The designer is not crazy to ask you to power this with a car battery. It is because in the DAC game, particulary with a 16 bit dac - power supply is crucial to obtaining good sound. NAIM with their flagship cd555 CD player charge you 4000 GBP for the power supply alone. Charles the designer says, you can get pure power supply from a car battery. I'll take the car battery any day over a 8000 dollar Power supply unit. This Dac also doesn't have a digital filter. In PCM technology you can either have perfect frequency response with some time smearing, or no or little time smearing, but this will affect the frequency response. So the treble is slightly a bit lower on this dac, but I will take this any day, and I repeat, any day, over a perfect frequency response. Once you listen to this dac with no time smearing and no or little ringing, you will not be able to anything else. I believe it is the time smearing that makes CD sound bad. I have compared SACD versions and CD versions of the same albums and this DAC can hold it's own against SACD in terms of musicality and enjoyment. (in fact I prefer the dac for sheer enjoyment)