how good are the non os dacs?

had the epiphanous vinyl experience and realize that i would like to bring my digital closer to the vinyl qualities i.e. smoother with more natural tones but retaining good resolution. i have my eye on the non os dac by small company but the opinions thus far are great. could a few of you digital experts comment on how good non os really sounds? love to hear recommendations from those of you that have listened to them in comparison. thanks
I have found that non-OS dacs tend to have a bit better clarity, body and texture to instruments and voices. I have also found that they tend to have great transient attack as well. The downsides I heard were a slight lack of "air" to the soundstage compared to some of the better upsampling dacs and players, and a tad less detail of non-musical information. If you do not have real good power conditioning and don't want to spend a fortune, check out the Ack DAC 2.0 (battery powered). What are you using for amplification and speakers?
I recently went to a Non OS DAC and have had a few epiphanies with it. I would say yes it does remind me much of what I like about vinyl best. I don't know if I can completely give the credit the fact that it doesn't oversample but I was guessing this might be part of it.
"Addition By Subtraction"; this is the best description about NOS DACs I can provide.

It is due to the fact that NOS DACs 20KHz sine wave looks like a ladder. This means that the top extension is smeared, resulting in lusher presentation. So many audiophile like this, so it is not necessarily a bad thing.

I'd vote for OS though. :-)

I disagree with Bigshutterbug, on OS players exhibiting more air. NOS players can as well, if they are made right. My NOS DAC excels in hf detail, including spatial clues. It's delivery is far more natural than any OS player auditioned here. OS players always sound forced.
My NOS DAC excels in hf detail, including spatial clues.

Would you please elaborate? What make is your NOS DAC?

so, thus far you guys are very happy with the non os dacs. that is a good recommendation towards that direction. can anybody check out the promitheus website and tell me if technically this dac looks sound. saving 500.00 vs the audio note sounds good to my wife and the checking account. thanks.
Alex, there is nothing smeared nor lush about my system sound. Layers of detailed sound are carried riding on a supremely musical sound. My highs cannot get any more airy.

My DAC is a one of a kind built on an Audio Note circuit board.
I changed my mind about the Promethius. Upon studying the board, and
correlating research in DIY forums, I would be very wary of this DAC. I may still
consider buying it, but there will have to be some more positive reading in the
as i am no engineer, what seems to be the concern in the design of the dac. i respect your hesitation and would like to hear what you think is a problem.
I am fence sitting right now. Though some of the detractors don't care for it, the TD A1545A chip is OK with me. It is the asynchronous reclocking that gives me pause. Some folks well learned in electronics theory don't give this type of clocking any credence.

I would love to try it against what I have, but this Malaysian company does not take non-defective returns. That means I am stuck whether I like the DAC or not.

Critics of the NOS sound are listening to something I never have had the displeasure of hearing for myself. OS is often grainy, and bright. NOS DACs are not grainy, and the highs can be extended and very sweet. It is true some builders roll off the highs to the benefit of seductive mids, but that is a designer's choice.
i assume that the term "non os dac" means 16/44.1 khz .

there are differneces in sound between 16 bit non upsampling dacs. some use op amps, some do not. some have tube output stages, some do not. the caps used in the signal path may very.

thus there is no generic sound to these dacs. i own three of them and each sound differs from the other.

there is no point in generalizing. just as there is no value to make general statements about other components.

by the way i have not heard any lush or euphonic digital components in current manufacture. if anyone is aware of a very tube-like sounding digital product, in the classical sense, please let me know. i'll buy it myself.
mr tennis,
i was very specific in the dac i was most interested in if you want to comment on that one or any of the three you own. the adjectives used indicate that the listener enjoys the presentation and i believe that is what this is all about.
NOS vs. upsampling I have been able to do direct comparisons on the "Fly" with a touch of a button in the past.. NOS has a bit more body, more intimate and even meat in the middle midrange in your face, but pretty smooth, and with many transports can add weight to the lows yes..

As for Air, soundstage, its good and more like sitting in the recording studio..

Using upsampling definitely adds a little bit more of synthetic air, and causes a slight enhancement in surround sound type approach.. But can be sharper sounding in the end as the highs seem to carry more air exactly because they are a little more enhanced thru upsampling it seems.. Bass, well it depends its still deep, but more separated, so it might be as punchy but more spread out.

By the way fact is some recordings if they are just bad, or really need something can benefit from one type or the other of Dac, upsampling can help if its just a really compressed sounding recording, but to me is not as natural sounding, so yes Vinyl type sound is a little easier to mimick via NOS if you ask me.
Assuming you mean 16/44.1 by non OS DACS, the two that have auditioned (and own one of them) does sure come close to a good Vinyl rig experience. Undertow describes this sound very well. All the notes sounds like real music and can tell what instruments the sounds originates from- acoustic or electronic. Human voices are so natural and real and you can also hear 'inner' sound. Less to zero sibilance.

I also have auditioned many OS DACs (and own one of them) and can audition on a fly. Again, Undertow describes this sounds very well. Almost always, weight on the OS DAC notes is comparatively lighter- lower and mids, exhibits more air, tend to have more sibilance (compared to non OS DACs).

I find myself listening to non OS DAC for serious listening since it compares to my Vinyl set frighteningly well. The OS DAC does a good job but not as well.
hi djwilbourn:

i own the promitheus dac and two others. it has a lot of resolution and does not possess the characterostics that others have observed regarding os dacs.

the other two dacs, the paradisea and the exemplar little dac are also very detailed. i find the paradisea dac to be the "sharpest" sounding of the three.

i compared the dac in my vincent cd player to the three dacs. the differences are not that great. of course, the digital interconnect is key as well as the analog interconnects.

i reiterate that it is counter productive to make general statements about non os dacs. there are differences between them.

i also have not found any lush, rich or euphonic digital components which are in current production.
thanks for the responses so far, i am getting a great impression of pros to this design and the limits of its capability. mr. tennis, since you own the one i want, how pleased are you with it and do you feel it was a good investment? nill the pill, which one do you have? thanks again for the input
Undertow did a very good job of describing what I hear as differences between the two... He said it better than I could have. NOS dacs have plenty of detail, but as he stated OS dacs produce a soundstage that seems more airy or larger in an artificial way...
hi dj:

i don't think much of it in its present state. it needs all silver wire and rcas removed. at that point i will have a better idea whether it is a good dac.
Hi Djwilbourn,

I have a Zanden 5000 Signature DAC (Non OS) and a Metronome C2A signature DAC (OS)
ok,so i have spent some time listening to a buddy's higher end system and liked his digital sound. came back to mine with a known cd and noticed that mine does many things well. however, i was able to pinpoint what annoys me about the sound. distortion in dynamic passages, especially in the upper treble. mine sounds good until there is strong burst of dynamic energy. so is this the fault of the power supply, op amps or what. in addition what dac/player do you guys recommend under 600.00 that can combine smoothness and handle these dynamic passages. thanks again
I own Audio Note DAC2.1 Signature.Non OS DAC.I am more than pleased with the sound.It is more body,more natural, and also a bit warmer than other digital gear i have heard.BUT...this does not come at the expense of dynamics.Dynamics is still great.I think my DAC is very natural sounding and efortless.I rolled over 12 different kinds of E88CC tubes in it or 6N1P.Every time speed and dynamics are not a problem.I expected problems there, if anywhere.
Bass is extremely good.Midrange is clear,open and natural.Treble is brilliant.To my ears - no objections.
Just my opinion.
well, i thought i would update this thread that i started. i borrowed a well regarded non os dac that had obviously better bass and dynamics than mine but i never heard anything that really wooed me into enjoying it. then i got back on the internet and researched until i had headaches, dizziness, and a pissed off wife. so, i finally decided to just try something on a whim, i won an adcom gda600 dac off of ebay with a well regarded chipset and dual power supplies. it sounds great, very natural and unforced. piano sounds phenomenal and it has a magic to it that i have not heard in my home in years. so i am pleased. the digital fatigue that was subtle but driving me nuts is gone, hooray. thanks for the input.
Always a design out there that can do better no doubt! Glad you found a good match to your taste, because thats all it comes down too :-)
Non OS Philips 1543 or 1545 based dacs really show their age. I find they sound a bit congested when playing symphonic music but they can sound smooth. Not very resolving but can sound nice sometimes matched with the right components.
I have a 19 years old Micromega DUO with a TDA1541 chip, is it a NOS DAC?

you guys make me want to hook it up again ... it was considered very musical at the time but totally loose out in upper frequency detail. But it was a true enjoyment to listen for hours.

(BTW is it worth anything?)

i ran across the 1541a chipset in my research and with the correct implementation it is regarded as one of the best ever, so it might be worth a revisit. obviously, what the rest of your system contributes to your sonic picture matters a great deal i.e. metal vs. soft dome tweeters, tube vs solid state amp

Thanks for the tip. I wonder if the veiled presentation is jitter related? Back then when the product was launched, jitter wasn't even a topic. (after that they switched to bitstream chips which to my ears, sucked)

It's quite an interesting cos it has a volume control and a buffer amp built in - I'll try to hook it up to my power amp directly with my PC/toslink and see what happens.