I think a lot of stuff uses the 1792 and the '94 is said to be an upgraded version of that chip. Google and ye' shall find.

Yeah the pcm 179x series of dacs is good stuff, probably my 2nd favorite dacs behind the top of the line AKM chips. The 1794 in particular is used in a dvd players (the denons) and a number of cdp's across pretty much the whole price range. I believe the 1798 is the latest dac in the 179x family and it is used in some very high-end cdps like http://simaudio.com/moonsupernova.htm

Yeah, I've been waiting for a good DIY AKM based board to go all crazy on. Anything out there yet?

I'll keep my eye on this new twisted pear though... the OPUS wasn't any better than what I already have.

My AQVOX MkI uses 2x PCM1796. It sounds nice, even though my Stello beats it (uses AKM4395 IIRC).

I wish someone came out with a good PCM1704 design.

I think the VDA-2 uses the PCM1794, as well as the Corda Opera.

It probably depends more on the design than the actual chip. For example, I'd never look for a Cambridge Audio CDP, but love the Regas, and I think they use the same DAC...

oh and the Denon DA-500 if I can find one

You certainly can't have either of mine

I wish someone came out with a good PCM1704 design.

The DA-500 is a 1702 design, and the last stand-alone DAC Denon made AFAIK. The 1704 is in my DVM-4800, but I never got around to my comparison between the two. I'm still curious just how much of a difference there is.

So I was mixing changes. There are updates to the original Opus design as well as a totally new DAC.

I see. I still think the 8740/8741 should be buffered right at the output, and additionally I'd like to see use of film caps rather than electrolytics (though the Silmic II is a very good cap as far as electrolytics go). I know the Wolfson datasheet specs 10uF lytics right on the output, but it also specs an antiquated op-amp of relatively low performance in the LPF, so I'm not sure much deference should be accorded, and buffering the output directly seems more likely to preserve maximum performance since the dac will see a much easier load. For the i-out dac, I think "passive" I/V is bad news from a performance standpoint. It's an imperfect conversion to begin with, and in addition it seems as though it would be exceedingly difficult to get the full dynamic range. On top of that, from what I understand the PCM1794 has a current offset which, on a passive scheme, can result in offset at your output. Putting the active I/V on a seperate board isn't a good idea, either.

I love my Opus, but I'd put something else together if I thought it'd be better (without being ungodly expensive). I've considered getting a Pico and using that (ludicrous as it sounds), but I'd hate to use a 1/8" to RCA cable.

I've considered getting a Pico and using that (ludicrous as it sounds), but I'd hate to use a 1/8" to RCA cable.

Doesn't the Pico have RCA out on the back?

Doesn't the Pico have RCA out on the back?

You're kidding, right, there's no fracken way the Pico has the room for RCAs.

You're kidding, right, there's no fracken way the Pico has the room for RCAs.

I got it confused with the AE-2.

I got it confused with the AE-2.

No worries, the pico is seriously small.

Granted, I am the last perspon here to comment on a DAC, but the OPUS is _at least_ up to the E5 / Zap Filter out I just turned over, with arguably more artifacts - cartainly no worse than. Now, once I get some competent balanced dynamics (the Denon 2k ain't that can), I can better try it against the Azur 840c. Not fair, and not the same quality, but _for the relative $$_ , a VERY competitive choice. This from a $60 dvd transport...

In practice, the OPUS is a legit contender in the sub $400 space, and can be done for not much more than $250, powered, depending on casing and jewelry. Since mine is with the amps, it was right at $200 implemented with a receiver.

ok so i'm pretty much stuck choosing between the opus and the MSB Link III AND the headroom microdac

Leaning toward the Opus because of both USB and spdif inputs AND its DIY!!!

MOTMOTMOT etc etc

but the OPUS is _at least_ up to the E5 / Zap Filter out I just turned over

Yeah, at our mini-meet a bit ago, we compared Opus w/ Ballsie versus E5 w/ zap and they were remarkably similar.

ok so i'm pretty much stuck choosing between the opus and the MSB Link III AND the headroom microdac

Leaning toward the Opus because of both USB and spdif inputs AND its DIY!!!

MOTMOTMOT etc etc

J

are you considering the standard MSB Link III or the Nelson, and with or without the power supply?

U

I don't know much about it but I was told by someone that it was more like $400-500 to build a single ended Opus, is $200-250 more representative of the actual costs?

I don't know much about it but I was told by someone that it was more like $400-500 to build a single ended Opus, is $200-250 more representative of the actual costs?

I don't see how it could be done for $200, no way, no how.

The bare modules cost $175 from TPA, add a trafo and you're now at $197 + shipping. And that's with no connectors, no wire, no chassis, etc. So I'd estimate that you're looking at ~$300 for just the parts for a SPDIF only Opus, probably more. If you want USB add another $75 in parts, same thing for the Ballsie. $200 is impossible.

Oops, my bad... forgot the trafo... with trafo in my existing case was about $220 ($175 +$45) - I always forget about adding in stuff that I already have sitting around, but still, let's call it $300, without USB or Ballsie.It also helps we have an EXCELLENT surplus store here in Dallas that blurs my costing. Tanners and Altex just make things a whole lot ea\sier and quicker, well, and cheaper.

BTW, if anyone wants a Ballsie, digital supply, and trafo (reasonable), lmk, as I chose NOT to implement the Ballsie path.

Granted, I am the last perspon here to comment on a DAC, but the OPUS is _at least_ up to the E5 / Zap Filter out I just turned over

From the comparison we did at a recent meet, the OPUS with zapfilter sounded identical to my Eastsound with zapfilter... the OPUS with the ballsie output stage seemed to be missing something, but it may just have been a gain matching issue as the zapfilter has higher output. They were very close though in any case, which is why the OPUS is off my radar for now.

Ok, that clears things up, thanks.

BTW, if anyone wants a Ballsie, digital supply, and trafo (reasonable), lmk, as I chose NOT to implement the Ballsie path.

I might have to take you up on that soon

J

are you considering the standard MSB Link III or the Nelson, and with or without the power supply?

U

Standard with no upgrades and no PS

The shipping is 100 for just the DAC which brings the price up to 350 but I really want the upsampling upgrade

oh and anyone have any thoughts on the EMU 0404 USB? The other site loves them