Need a DAC recommendation

It has been my experience that there isn't a great deal of information out there regarding the performance of all the new DACs coming out--especially for more affordable ones.

I need a new DAC and I'd like to spend less than 600 used or new, the cheaper the better. USB would be nice, but I'm probably going to use digital coax mostly from my computer. I only listen to FLAC and I always try to obtain the highest bitrates possible, so the DAC has to be able to accept at least 24/96 (192 or higher would be even nicer, as would upsampling, but I'll take what I can get for the price). On my other system, I have a V-DAC with the V-Link usb/spdif converter and its not bad. Any advice would be greatly appreciated. BTW--Anyone try the VDAC II?
Music Direct has the Musical Fidelity M1 on sale for $619. This reportedly is an upgraded V-DAC with a choke regulated power supply. I'm waiting for mine to be delivered, as they are backordered one week. I use a V-DAC on another system, and I like it very much. I plan to use the M-1 with a V-LINK on a computer based system.The M-1 has favorable reviews.
The PS Audio DL III is showing up <$500 regularly - a nice, warm DAC with lots of input options and upsampling to 192 kHZ.

...add the V-Link and you've got a pretty potent and flexible DAC for <$650!
I can second the P S Audio Dac III. I have one on a second system and think it is a great bang for the buck product.
What about the new Apogee Duet 2?
Since this is a technology that changes rapidly, and we already have the ability to make DACs that can achieve much higher bitrates, I was hoping that there is, or will be, a great new generation of affordable DACs on the market. Seems to me that the majority of DACs on the market are a bit obsolete Months ago, I saw buzz about an exciting DAC from Asus:
Upsamples to 32 bit/352.8Khz and is only supposed to cost about $250-$300. Now, I realize that Asus isn't the prototypical audiophile company, but they make a good soundcard, and maybe at this point it'll take a computer electronics company like Asus to make something that renders the competition obsolete at a fraction of the price. Unfortunately, there's been no news of this DAC since then. Anyone know of anything on the market that can achieve upsampled bitrates higher than 192 for anywhere near that price? Also, does anyone have any experience with the HRT streamers? I wish there were more current DAC reviews out there, but I can't seem to find that many.
I would like argue the importance of the overall design of a DAC, such implementation of the output stage (opamps, tube, discrete fets)and power the supply, which some say is more important than the dac chips and bit rates.

However, taking this 180 degrees, I'm blown away by the performance of my $150 HRT Music Streamer II (after 300 hour burn-in).... which uses cheap opamps but asynchronous USB technology... I think that the $350 HRT II+ should be on your shortlist if USB is all you need.
Funny, I would recommend a several much older DACs that have great analog performance, quality power supplies but not the "latest and (supposedly) greatest" chipsets.

My experience with most of these mid price latest/greatest chipsets is that sure, they up the bit rate, but in the end don't sound as good!

My recommendations would be a CAL (California Audio Labs) Alpha tubed DAC (preferably, since you care, the 24/96 version). These are typically around $500, but usually sell almost instantly when they do list.

Another strong recommendation would be the Kora Hermes (which does upsample) and is also a tubed DAC. This may be just above your price range, but will kill (based on those I have listened to) of the current 7 pound latest chipset dacs.

I have had some great DACs, including DCS, EMM Labs, Esoteric and others. I can tell you that these are great dacs even running at 16/44 absolutely kill these latest/greatest DACs (running 24/192 etc.). Remember, at some point the DAC needs to send an analog signal. Doing this well requires a good analog circuit design and componentry (HQ parts) and a good power supply (like in a preamp). Good power supplies cost money and have good weight to them. The best chipset in the world can't make up for a bad power supply and analog circuitry (take a look at all the HT Receivers with super high "bit rate" upsampling). They still sound like crap.

My point, you can go for super high bit rates, but this won't guarantee (or frequently deliver) better performance if the other issues (which are just as important) are not addressed.
Agreed, the importance of the Analog circuit and quality of components is crucial. But in the terms of value, digital has come a long way when we look at sub $600 category (i.e. this thread), and the $150 HRT Streamer in my office system smokes my old Cal Audio DX-1 (a $600 player in 1994)in terms of resolution and soundstage. I think, too, that the current technology does a lot better job addressing jitter.
I understand the need for good analog components, and I love the warm sound of analog+tubes...if I could have the best of both worlds that'd be great. I guess i'm kind of a bitrate junkie--my entire music collection is in FLAC, and I strive so hard to find the highest quality files, so I really want a DAC that can stand up to them on the digital end. A lot of the DACs with good analog components mentioned above are a bit hard to find. A few questions come to mind--does a tube DAC really add a lot of warmth to the sound? I don't have any tubes in my setup yet for budget reasons, and being able to add some tube-sound with a DAC would be nice. Also, how do the HRT streamers stand up to the music fidelity DACs and the PS Audio DL III? My only qualm with HRT is that they are USB-only, and I like to use digital coax. Is the asynchronous USB as good as digital coax? I've never used asynchronous USB. Does the HRT II+ add a lot of quality over the HRT II? I think the M1 DAC may be at the top of my list right now, but at that price range are there any others worth considering?
Check out the Emotiva XDA-1 DAC. It has 2 coax inputs, an AES input 2 optical inputs and 1 usb input. The analog output stage uses all discrete audiophile parts (no opamps) and it sounds really great using an hp laptop running J Rivers Media Center 16 in WASPI output. All files are ripped to FLAC.

The unit is a steal at a reduced price of 299.00! The only drawback is it doesn't do 24/96 on usb. I am waiting for a Musical Fidelity v-link to convert the usb to coax so I can try out some High res downloads.

I would not pick a DAC based on tubes or SS, but just on sound. Can a tubed DAC add warmth? Sure. Do they all? No. Take a look at the Audio Aero equipment (I had the Capitole a while back), it has subminiature tubes and imparts a high degree of warmth and bloom while many others do not, the MF Trivista, which also used subminiature tubes (I currently own this DAC, but its just sitting unused) is not what I would call warm or bloomy.

I understand the wanting for the high bit rate chipsets. But let's all be honest with each other, the costs of the chipsets is astronomically cheap (you see 24/192 bit rates in sub $100 equipment). Which goes to show what you are really paying for with a DAC. If the chipsets were the leading component that determined performance, 90% of the HT receivers would be outperforming the best DACs of just a few years ago. But we all know this isn't the case.

Don't get me wrong, I am not saying that the newer chipsets can't improve the performance of a component. But what I am saying is that a DAC with a "great" new chipset, but with a mediocre analog circuitry and power supply will not outperform a DAC with an older, lower sampling rate DAC with a very good analog set-up and power supply.

Take a great older model DAC (great analog and PS) and update the chipset and yes, I think it can improve based on the chip (new technology, capabilities, etc. . . ) but it can only increase up to the capabilities of its weekest links. Just like in a system. You can have a great turntable but a lousy amp and speakers and your system will no show what the table is capable of - same with a DAC with great/new chipset and lousy PS and Analog section. Wait until you hear this one....
If you will only be doing computer audio, then I urge you to research USB DACs. There has been a lot of development recently, and USB now handles high resolution files. There are two approaches, asynchronous (e.g.,Ayre, Wavelength, HRT, Wyred 4 sound) and high resolution synchronous (CEntrance, Benchmark). Within your budget, I recommend you'd look at HRT Music Streamer II+ (the II+ will have much better analog output stage and components than the II) or the II Pro if you have XLR inputs on your preamp. The CEentrance products should also warrant your consideration.
Is the high resolution USB as good as the digital coax? Depends on a lot of variables. How are you getting coax out of your computer? Musical Fidelity V-link or M2Tech hiFace Asynchronous USB To S/PDIF Converters? Or just a basic computer soundcard?
I am assuming the latter. Why don't you borrow the Musical Fidelity combo from your other system, and hook the V-DAC up both via coax and through the V-Link, and listen which connection sounds better. That should give you an idea what direction you should go, coax or USB
Audio GD nfb2 is fantastic value
The VDAC is a pretty spectacular unit considering the cost. Not sure your budget is going to jump you to another realm of performance unless you look to some of the older hi-end units mentioned earlier. Another one to consider from the same company is the MF Nuvista DAC of which I have never heard an ill word spoken of it.
Arni--you make a good point about borrowing the combo from my other system. For some reason, I haven't thought to do that(I have the V-DAC/V-Link set up at my gf's place) but I will bring it home and compare the v-link with straight coax into the v-dac. BTW, my soundcard has a dig coax output, and that's how i'm getting it.

In regards to the argument about having a good power supply, I agree, but this raises the question: how does that reflect in the quality of the HRT DACs, which are only USB-powered? In addition, would you say its worth adding an external power supply to the V-DAC? At that point it might just make sense to go for the M1 DAC. I haven't heard any mention of the Cambridge Audio DacMagic--how's that compare? I'm also curious about the Emotiva XDA-1 DAC, which I hear a lot of people talk about. Has anyone had the opportunity to directly compare anyone of these great value DACs(emotiva,MF,HRT,PS)?

P.S. If anyone cares, these are my current setups:
1)Totem Rainmakers + NAD C375BEE (Love this combo)
2)B&W CM7 + Rotel RSX-1056 + V-Link/V-DAC (Like everything except the Rotel)
I think you have a great combo with the rainmakers and the C375BEE to start with!
A lot is going to depend on the quality of the digital out of your soundcard- i.e., what route to take. The V-DAC appears to be one of those rare over achievers at its pricepoint- except for USB input. I don't think the Cambridge DacMacic or the Emotiva will make any more real music.
The PS Audio Digital Link-III recommended above has a discrete output stage (no opamps), 192k capability, and on the used marked, is a great value. I'm positive it will better the V-dac. However, its USB input is old school limited to 48/44.1. It would be my recommendation based on your original post/question (coax digital in), but I suspect that the V-link will outperform your coax soundcard-output by a huge margin.
You raise a good point about the power supply to the HRT streamers... I don't know how they do it... but they claim to isolate the power from the audio - and it sure sounds good. Don't overlook the CEentrance Dacport XE, it may even be better than the HRT.
In my main system I have Cullen modified (stage IV) PS Audio D-Link-III fed by Squeezebox Duet. The sound is extremely airy, neutral detailed, but still warm with strong bass. I have never heard an un-modified unit, but I suspect similar virtues would be there too. You could pick one up used for about $450-$500, and add a good USB to Coax converter that does 24/94- or even 192- and be just a tad over your posted price tag.... or do a HRT Streamer II+ and be done with it....