Lloyd first brought this DAC to my attention, but after searching I still can't find where. So here's a new thread to focus on it. Because there are pics of the internals I figured that some observations about the article and what's inside the box might be interesting to DAC lovers here. Any takers for some technical analysis?
It is an interesting design. Not at all new - there have been many DIY projects (some of them are even available on ebay in semi DIY form from Chineese vendors) based on the concept of paralleled 1543 DACs.
What is interesting is that he uses transformers for I/V conversion and no output stage per se (that is why he needs so many of those chips - otherwise he would not have enough current to drive the outputs). Another interesting feture is the use of super regulators throughout, fed from 5 separate transformers.
Even the M2Tech OEM board he uses (this is the M2TOEM-01 model if I'm not mistaken) is fed from the two separate regulators and transformers - he mentioned that he doesn't use USB power, which means that he needs AFAIR +5V and +3.3V supplies to power it.
I'm not a big fan of 1543 chips, as they sound too dark for my tastes. But the whole NOS concept is interesting - I'm a big fan of Metrum Octave DAC myself.
Yes there are very many DIY projects and PCBs on eBay (and Taobao) - I have some of them myself. Indeed TDA1543 was my very first initiation into the sound of NOS. I was skeptical at first but curious enough to try it - wasn't impressed at first, partly due to the darkness you mention which I attribute to the NOS droop (suck out of HF energy in the top two octaves). Where did you see transformers being used for the audio? - the two big bolted down blocks in the pic near the output sockets looked to me initially like trafos but it turns out they're just huge caps.
I felt the Octave was a real inspiration in that the designer, Cees, boldly went away from traditional audio DAC chips. It encouraged me to spend more time looking elsewhere for DAC chips too. Certainly its a milestone design in my estimation, rave reviews and yet still quite affordable. Incidentally the Octave now has an older (and much dearer) brother - new review here : http://www.6moons.com/audioreviews/metrum2/1.html
Yes sorry, ofcourse caps not transformers - I thinking about the other design writing this.
I know about HEX. I'm waiting for the call from my dealer to borrow one. I have Octave at home which I bought out of curiosity (there was no dealer at Poland at the time when they camo out, so had to buy one to try).
Yes, curiosity for me is the highest motivation for buying something. Just as Cees did me a favour by scratching off the name of the DAC chips - I might not have been curious about which ones he'd used had he not
I always try to sample gear that gets rave reviews. Sometimes - as in the case of Metrum - it turns out to be a revelation. But sometimes - as in the case of Devialet - it ends up as a disapointment.
Yes the Metrum is one of the DACs that's helped me to come up with my hypothesis for what in the main is wrong with digital sound. Because by traditional measurements it does exceedingly poorly yet nobody I've heard of dislikes the sound it gives them. What was wrong with Devialet? You're correct I think about the DAC chips, I came to that same conclusion a while back.
@Elberoth Just saw your listening comments over on the Devialet thread so received my answer. What you say fits with what I'm finding out about DACs. Probably the Devialet measures OK on THD, where it will fall down is in noise modulation, for which there's no standardized measurement. I recognize the signature sound from your (and Amir's) excellently detailed descriptions so thanks for putting them up
Sorry for the delay in replying. I was almost flamed in that thread. I should have forseen that audiopiles have a very personal relation to the gear they own. Thankfully, I was not alone in my assasement.
Even if you had been alone in that assessment and not supported by Amir's, I'd still have gone with your impressions. The supporters of Devialet don't come across as credible witnesses in my estimation - as you suggest, they're rather attached to their purchases. Post-purchase rationalization is a force to be reckoned with No, I haven't heard either the Octave or the Hex, just know of them by repute. As a designer I'd not waste a dealer's time in asking for a demo as all I'd do is take away any good features of the sound and figure out how to work those into my designs. No chance of a purchase out of me