• Grace Design m903 Reference DAC / Preamp / Headphone Amp Review

    The orange glow of my McIntosh MC275ís KT88 tubes was juxtaposed with the green glow of the Grace m903 power button. This combination of old-world and modern component design, both internal and external, was the only saving grace (no pun intended) for the m903. Matched with a tube amplifier the Grace m903 came to life more so than with any solid state combination in my system. At the expense of resolution this tube trade-off produced a pleasing sonic signature but nonetheless was not enough to get my toes tapping or give me goose bumps. I really wanted to fall in love with the inanimate object that is the Grace Design m903, but the more I tried the more frustrated I became. Was it my lofty expectations or a lack of system synergy? Was it my ears or simply a matter of taste? Any or all of these four reasons may explain my conclusion that the Grace Design m903 is a good but not great all-in-one DAC / Preamp / Headphone Amp.




     


     

    Comparisons

    Perhaps Iím being a bit too harsh on the Grace Design m903. After all it sounded better than the formerly C.A.S.H. listed Benchmark DAC1 HDR in a direct comparison. However, when I reviewed the DAC1 HDR in May 2009 and subsequently placed it on the C.A.S.H. Listlink computer audio options were less than endless. 24 bit / 96 kHz playback via USB was wonderful and the DAC1 HDRís adaptive USB transfer mode licensed from CEntrance was one of the best available. Today the DAC1 HDRís USB implementation is a bit long in the tooth. Since May 2009 asynchronous USB transfer mode has become all the rage as has support for sample rates up to 24 bit / 192 kHz and higher. As time passes and competition heats up good component designers are pushing boundaries producing better sounding products with more features. The Grace Design m903 has many more features than the DAC1 HDR and sounds noticeably better in my system. In addition to the very different design of the m903, as compared to the DAC1 HDR, my complete audio system has changed since my DAC1 HDR review. My system is much more resolving and revealing of component differences than at any time in CA history.

    Unfortunately better sound than a competing component doesnít equate to a CA recommendation. Thereís a subjective continuum of sound quality from the worst to the best. Near the middle of that continuum rests good components like the Grace m903. Higher up on my sound quality continuum is components like the Bel Canto DAC 1.5 ($1,395), Ayre Acoustics QB-9 ($2,750), and the Berkeley Audio Design Alpha DAC Series 2 ($5,000). Major League Baseball teams donít get to complete against only those teams with the same payroll. Similarly evaluating sound quality should not be done in a vacuum or strictly by price points. With that in mind I donít believe Iím being too harsh on the m903 although I am holding it to a high standard. Compared to many other DACs in all price ranges the m903 is a home run, if not grand slam when it comes to features. In terms of sound quality the m903 is a base hit up the middle. The over all sonic character of the m903 when used with solid state amplification was veiled and unlively with an extremely tight image located too deep into the soundstage for my taste. Switching to a McIntosh MC275 tube amp brought the sound to life and moved the image much closer to my listening position. The major trade-off when using the MC275 in this particular setup was loss of detail for a lush, lively, and sweet midrange. No matter what amplification I used there was a consistent lack of low level detail through the m903. The finer details and nuances of recordings could not be heard unless the volume was louder than my normal listening level. This louder level became fatiguing after about thirty minutes. I had to choose between more detail with sore ears or less detail with comfortable ears.

    Comparing the sound quality of the m903 to that of the DAC1 HDR was revealing of differences between the components. The DAC1 HDR sounded more washed out and less punchy when reproducing the electric bass. Comparing the sound quality of the m903 to one of my current references the Berkeley Audio Design Alpha DAC Series 2 revealed sonic shortcomings beyond that of component versus component. After listening through the m903 for weeks playback through the Alpha DAC Series 2 in combination with the Alpha USB left me in awe. Goose bumps, toe tapping, and a little sonic disbelief describe the experience and my thoughts. Air around instruments, transparency, low level detail, and soundstage were all significantly better through the Alpha / Alpha combination. Based on price this sonic difference should be expected. Regardless of price itís always healthy to compare components in for review with components I consider my reference. In this case I was reminded of the gap that exists between high performance components and how high my bar is set when comparing sound quality.

    One pertinent comparison that I would have liked to conduct was the m903 against the Bel Canto DAC 1.5. Shortly after my DAC 1.5 review I sent the DAC back to Bel Canto thus eliminating the opportunity to compare the components. Basing my opinion strictly on memory I prefer the sound of the DAC 1.5 in my system by a large margin. I wasnít longing for detail and didnít experience any unlively sound with the DAC 1.5 like I had with the m903.

    My-SystemPeople should not read too much into my opinion about any of the components mentioned in this review or any review for that matter. My system is unlike any other system just as my ears are unlike any other ears. The biggest "instrument" in all systems is the room. Nobody other than myself listens to music in my listening room. If someone plans on purchasing my house with my current system intact and somehow mirroring my ears then they can take everything I say to heart. Otherwise please be cautious and listen to the Grace Design m903 in your own system concluding anything good or bad.





     

    Feature Fest

    The Grace Design m903 is truly a feature-fest. This all-in-one DAC / Preamp / Headphone Amp not only looks great and is built like a tank, it offers all the features of todayís best designs. Many of the features such as the publicized asynchronous USB transfer mode and high precision analog volume control, playback and front panel display of frequencies up through 192 kHz, and both balanced and unbalanced in/outputs are somewhat visible to the naked eye. The features that impressed me just as much and demonstrated the high level of expertise Grace Design has in designing components were located behind the scenes in the Setup Menu. The ability to set a default power up level, lock the output toggle switch, independently control the three analog outputs or use exclusive output mode that mutes the unselected output are some of the very nice features not found in most consumer products competing with the m903. Also included in this Setup Menu is the ability to enable display dimming. Once enabled the very bright display will dim after four seconds of inactivity. I consider this a critical consumer feature as I listen in complete darkness frequently. When the display is illuminated Grace has cleverly implemented a tiny decimal point in the lower right corner to indicate the volume is 0.5dB above the displayed whole number. This enables a smaller display to indicate precisely what level within the 95dB range the m903 is current outputting. Embedded into the analog volume control is a three step acceleration curve. This is a great feature that I used several times per day as I frequently adjusted the volume in-between system changes. The volume encoder has 24 positions that result in a change of 12dB in 0.5 dB steps when itís turned one complete revolution at a slow pace. When encoder rotation speed increases the steps increase first to 2.0dB then to 4.0dB. Over the course of a couple decades Iím sure users will save at least five minutes of their time. Joking aside, this is a very convenient feature that I now look for in all similar components.

    Interfacing the m903 with a computer music source can be accomplished numerous ways. The m903 supports AES/EBU, S/PDIF electrical (coax) and optical (TosLink), and high speed asynchronous USB using Gordon Rankinís Streamlength async code. Every digital input supports sample rates from 16 bit / 44.1 kHz through 24 bit / 192 kHz. I listened through the AES and S/PDF coaxial inputs fed from an Aurender S10 music server. Running through playlists containing music at all supported sample rates the m903 handled the frequency changes without flinching. Other components Iíve had in my listening room really struggle with sample rate switches depending on the clock implementation. The Aurender S10 front panel display indicates the frequency of the currently playing track. It was comforting to match this frequency with that on the front panel display of the m903. While not a true bit perfect indicator this frequency display would let the listener know if something major like sample rate conversion was taking place. For example connecting the Olive O6HDlink music server to the Grace m903 via AES illuminates the 96 kHz indicator clearly showing the O6HD resamples all digital output to 96 kHz.


    The Aurender S10link music server has certainly changed my listening habits since placing it in my system. I usually gravitate to its wonderful iPad user interface and excellent sound quality. Once I switched to the m903ís asynchronous USB input fed from a C.A.P.S. v2.0 server I never look back. The async USB input on the m903 was no doubt the best sounding input. All music played through the USB interface was more coherent and ultra tight as opposed to the AES and S/PDIF interfaces that had a loose sonic character or a little lack of focus from the midrange down to the lowest frequencies.

    In USB 2 mode the Grace m903, and all other high speed USB DACs, requires driver installation because Windows does not yet support Class 2 Audio. Class 2 Audio is what provides support for frequencies higher than 96 kHz. Versions of Mac OS X at or above 10.6.4 do not require any driver installation as they support Class 2 Audio out of the box (or straight from the Internet in the case of Lion). The Thesycon driver used by Grace and a limited number of other async DAC manufacturers is one of the best drivers available. In my experience the Thesycon drivers work 99.9999% of the time. Installation and uninstallation of these drivers has been flawless. The same cannot be said for other Class 2 Audio drivers.

    My software player of choice is J River Media Center 17. When supported by the DAC I use JRMCís WASAPI - Event Style output mode. This output mode lets the audio subsystem pull data instead of pushing data to the system and advantageously creates, uses, and destroys all WASAPI interfaces from a single thread. WASAPI - Event Style allows lower latency buffer sizes, and removes an unreliable Microsoft layer that causes the circling buffers to get out of order resulting in stuttering. In laymanís terms WASAPI - Event Style allows for a more direct data path to the driver / USB DAC. The Grace Design m903 supports WASAPI - Event Style perfectly. I tried all reasonable methods to cause playback problems between J River and the m903 but I was unsuccessful. Sample rate changes were immediate and gapless when track-to-track navigation was configured as such. My entire JRMC and m903 user experience was really a joy as evidenced by my affinity for this playback chain over the Aurender S10 / m903 combination.
     

    Caveats

    The back of the m903 has a couple semi-unique in/outputs and two caveats readers should consider. The m903ís physical USB input accepts what is called a Mini-B 5-pin connector. This in itself isnít a big deal. Flanking the USB Mini-B input terminal are two protruding round metal screws that no doubt result in a very strong long lasting design. Caveat one - Unfortunately this may hinder the use of certain USB cables. The m903 ships with the required USB Standard-A to Mini-B cable that works without issue. In advance of receiving the m903 I procured a Wire World Silver Starlight Standard-A to Mini-B USB cable. This cable features larger robust connector "surrounds" that impede the Mini-B termination from entering the Mini-B receptacle as far as the stock USB cable. The difference between the two cablesí penetration into the Mini-B receptacle is so minute I donít know what type of measuring device is necessary to quantify this difference. Fortunately I used the Wire World Starlight USB cable with Mini-B connector of weeks without a single issue. The cable does not come loose or cause any playback anomalies. In fact Iíve likely made a bigger deal of the situation than necessary, but I want to make sure readers are aware of a possible issue that would not come to light without first hand knowledge of the m903 and different USB cables.
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    The other semi-unique connections on the m903 are balanced TRS analog outputs. These are common in the professional audio world but few and far between on consumer devices. When I talked to Michael Gracelink, Founder of Grace Design, at the 2010 Audio Engineering Society (AES) convention at San Franciscoís Moscone Center he expressed his engineering preference for TRS connectors over XLR connectors and practically speaking said thereís no room for much larger XLR connectors on the m903. Shortly after this conversation I ordered some TRS to XLR cables and XLR to TRS adapters. I wanted to option to use my existing XLR to XLR cables with adapters and the TRS to XLR cables without adapters. The TRS outputs on the m903 are placed very close to each other due to the space restrictions of its small size. Caveat two - Unfortunately this will prohibit the use of large XLR to TRS adapters. The audiophile in me ordered very nice, expensive, and robust adapters only to find out they were too large to connect both simultaneously. I didnít think about the fact that adapters large enough to accept the XLR connector would be just as large as the XLR inputs Michael Grace omitted from the m903 design partly because of space restrictions. Fortunately the Mogami Gold TRS to XLR cables from Guitar Center of all places worked perfect.
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    Headphones

    One feature of the Grace design m903 that I did not dedicate much time to is the headphone amplifier. I listened through the m903 with a pair of Senheiser HD600s and Grado RS1s. Neither the most current models nor the most resolving headphones available. the sound quality was very good, but Iím not a regular headphone user with memories of many headphone amps for comparison. Making judgements on the m903 headphone amp quality may be a disservice to Grace and potential customers. Letís face it, thereís no place like Head-Fi for headphone information. Here is a link to Head-Fi user NA Blurís m903 reviewlink.
     

    Final Thoughts
    The Grace Design m903 is no doubt a well designed and constructed all-in-one DAC / Preamp / Headphone Amp. I would be remiss not to recommend all interested readers listen to the m903 themselves in their own systems and to read opinions from many other sources. My listening experience with the m903 is but a single data point among many. Grace Design doesnít get such high accolades and industry respect for making lackluster products. These guys are great designers, great people, and offer product support thatís second to none. It just so happens that the m903 didnít gel or have any real synergy with my current audio system. In fact it would be my pleasure to have the m903 back in my listening room in twelve to eighteen months for another go-around. I am 100% sold on the feature set of the m903. I believe this product has set a high standard with features other manufacturers must now consider obligatory not optional.

     

     



     

     




    Product Information:

    • Product - Grace Design m903 Reference DAC / Preamp / Headphone Amp

    • Price - $1,795

    • Product Page - Linklink

    • User Manual - (PDF)link

    • Brochure - (PDF)link

    • Setup Quick Reference - (PDF)link




     





    Associated Equipment:









     

     

     
    Comments 32 Comments
    1. AudioDoctor's Avatar
      AudioDoctor -
      After being burned by the Benchmark DAC1 USB due to all the hype that godawful (IMO) thing received, I have been extremely reluctant to purchase pro-sumer equipment. I was really hoping this was going to be different, the fact that Grace had licensed Gordons Streamlength Asynch code gave me hope that it was going to be a knockout device. If your review had been glowing, I would have ordered one tonight. But the more I investigate the Pro-Sumer equipment the more it seems that they know how to make very good technical stuff, but not very musically pleasing stuff. Specifically what got me thinking was your comment about the soundstage being so far back, is that not what you would want in a desktop monitor type situation? My guess is that in that situation it would excel, but that is not how most of us here would want to use it. I was hoping to use it as a semi-portable DAC/Head Amp. I am considering not doing that now, and perhaps getting an audition before I go ahead and commit nearly 2K to it.<br />
      <br />
      Thanks for the review Chris.
    1. aswillman's Avatar
      aswillman -
      Chris<br />
      <br />
      I got the Chord Company here in Wiltshire to re-terminate some balanced Chorus leads so one end was TRS. I use these in a desktop listening system with an Apogee Duet 2 with similar outs. <br />
      <br />
      It wasnt expensive at all and they fit nicely, certainly compared to the XLR/ TRS adapters. I think about £20 to £25 per termination.
    1. Mark Powell's Avatar
      Mark Powell -
      Veiled and unlively.... Consistent lack of....<br />
      <br />
      Why didn't you just say "It's crap"?<br />
      <br />
      And I see they use an odd way of displaying two of the speeds. Even at the fairly high price they save a few cents by eliminating a couple of LEDs.<br />
      <br />
      BTW - Who's this 'Gordon' who comes up quite often? He some kind of 'expert'?<br />
      <br />
    1. barrows's Avatar
      barrows -
      "BTW - Who's this 'Gordon' who comes up quite often? He some kind of 'expert'?"<br />
      <br />
      Yes. This is Gordon Rankin, owner/designer/engineer of Wavelength Audio, who makes guitar amps, tube based analog home audio gear, and some very good USB DACs.<br />
      He is also the developer of the "Streamlength" asynchronous USB code used in many USB DACs, like those from:<br />
      <br />
      Ayre, Aesthetix, Grace, Berkeley (the Alpha USB-SPDIF converter), etc.<br />
      <br />
      He was one of the first, if not the first, people to implement asynchronous USB for audio use.<br />
      <br />
    1. Mark Powell's Avatar
      Mark Powell -
      Thank you, I had wondered.<br />
      <br />
      Personally I will go straight to dCS when I want a new DAC. They also were 'among the first, if not the first'.<br />
      <br />
      Unfortunately part of their specification requires a buyer to win our National Lottery.
    1. SteveChicago's Avatar
      SteveChicago -
      ... he calls 'em like he sees them ...<br />
      <br />
      Thanks for being true man!
    1. cmidyet's Avatar
      cmidyet -
      for the great review. I was able to determine that this product was not for me. That is the best praise I can muster. To read a review and absolutely know that I am the wrong "target" customer is wonderful. So many times ...you have to read between way too many lines to figure this out. Thanks!
    1. thirdeye1969's Avatar
      thirdeye1969 -
      I think this review should have been prefaced as a review of the component as a DAC/PRE only. The initial conclusion that this component is merely a "good" all in one may be a little misleading since the headphone amp part of the m903 is certainly one of if not it's main feature. Not sure which all-in-one at or near the price range would be considered "better", or merely a different flavor.<br />
      <br />
      For reference, I use this component in a desktop listening station together with Beyer T1 headphones and Neumann KH 120 (Klein + Hummel) monitors and in this capacity it absolutely shines.
    1. Priaptor's Avatar
      Priaptor -
      straight to dCS, I recommend you look at competitive products significantly cheaper. I have and the Debussy while very good, at least in my system, did not perform up the grade of much cheaper competitors. <br />
      <br />
      I know people swear by dCS, but few have compared them, with the mindset that the more you pay the better (I have been guilty of that in the past, when money was less of an issue). I am also not one to try to rationalize my choice as I have no clue if my choice is best in other systems and quite frankly I would love to try two other DACs just to see, if I could ever get a hold of them.<br />
      <br />
      IMHO, dCS is overpriced and there are better DACs out there.
    1. beetlemania's Avatar
      beetlemania -
      >>>He was one of the first, if not the first, people to implement asynchronous USB<br />
      <br />
      that Gordon Rankin was the first to engineer and first to implement async USB. dCS engineered their own solution . . . after the Wavelength products were already available.<br />
      <br />
      But I had heard good things about the Grace, so am surprised at this review.
    1. sidssp's Avatar
      sidssp -
      I was planing to buy one because I like the idea of having a balanced analog input so that I could get rid of my preamp. But now I am having second thought. If it sounds like crap, what is the point of all those inputs?<br />
      <br />
      Are there better DACs out there that can double as preamp with balanced analog input?<br />
    1. One and a half's Avatar
      One and a half -
      To provide some criticism of the review, Chris doesn't compare any of the Apple players with J River. The m903 is certainly revealing enough to detect the differences between the two systems, Mac players the decided advantage.<br />
      <br />
      In addition, the USB U1 and U2 modes on the m903 are very different, the U1 mode, resolving to maximum 96/24 is certainly veiled whereas the U2 mode is crystal clear. I don't see a mention of this in the review. If you disconnect the USB, or if you remove power to the m903, the default mode is U1 and needs to be set to U2 again. U2 mode is remembered if you switch off the front power button.<br />
      <br />
      When using the headphone output of the m903, I have a lot of difficulty in distinguishing which performance has the better resolution, and can use either freely without any misgivings.<br />
      <br />
      I have the m903 for well over 9 months now and am very happy with it and would recommend it, especially for headphone use.<br />
      <br />
      The review is only subjective of one person's opinion and reproduction system, if it doesn't match your own, so what, Grace Design (and Benchmark) have many other buyers who are satisfied with their designs, otherwise these pages would be littered with negativity, or they would be out of business . I don't see much evidence of either.<br />
      <br />
      "Try before you buy" !!<br />
    1. bball3748's Avatar
      bball3748 -
      "Major League Baseball teams donít get to complete against only those teams with the same payroll."<br />
      <br />
      Did you just watch Moneyball?
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      <I>"Did you just watch Moneyball?"</I><br />
      <br />
      No, but I think I might see it one of these days. It looks kind of good. <br />
      <br />
    1. Mark Powell's Avatar
      Mark Powell -
      Priaptor,<br />
      <br />
      My reason is because dCS DACs use entirely their own circuitry and their own firmware. There are no DAC chips involved at all, off the shelf or 'custom' Same for the USB input. Might not be a logical reason, but it is the one I have.<br />
      <br />
      It's all done in programmable gate arrays. That does not make it inherently superior, in principle they could just use the arrays to copy the functions of an off-the-shelf chip, but they don't.<br />
      <br />
      They use them to implement their well-known 'ring DAC'.<br />
      <br />
      Whether they are going along this complicated and difficult path because they genuinely believe it to be superior or whether it is a marketing ploy enabling them to charge high prices I have no idea.<br />
      <br />
      But I am rather suspicious that many of the other high-priced 'much acclaimed' DACs available use very much the same off-the-shelf chips as the cheaper ones. Although some stick a tube or two on top to be 'different'.<br />
      <br />
      As for the actual topic, the Grace DAC seems to be just another of the many pretty high priced 'run-of-the mill' DACs, rather similar to the Benchmark, which I have seen described here as both very good and 'godawful'. The chips in all these things are much the same, as I have said.<br />
      <br />
      Personally I use a 300 dollar Cambridge Dacmagic. To me a Grace or a Benchmark may not be a big enough step to make a cost-effective improvement. Not a difference, but a real improvement. The Debussy may (only 'may') be. But certainly not without a minimum of a week-long home trial. Spending quite a lot on 'upgrades' at the moment, mainly inspired by the stunning (to me) results I have had with computer audio after only a few weeks. Best carry on spending the money while I am still in the mood to do so!
    1. losingmyreligion's Avatar
      losingmyreligion -
      <br />
      "The audiophile in me ordered very nice, expensive, and robust adapters only to find out they were too large to connect both simultaneously. I didnít think about the fact that adapters large enough to accept the XLR connector would be just as large as the XLR inputs Michael Grace omitted from the m903 design partly because of space restrictions. Fortunately the Mogami Gold TRS to XLR cables from Guitar Center of all places worked perfect."<br />
      <br />
      <br />
      Chris,<br />
      <br />
      This seems to suggest that the analog interconnect cable you used as the basis for your review is the $39 Mogami Studio? <br />
      <br />
      This also suggests that this cable was new to your ears & your reference system?<br />
      <br />
      please correct me if I've misunderstood.<br />
      <br />
      clay<br />
      <br />
      <br />
      <br />
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Hi Clay - Good question. I actually have cabled my entire system both digital & analog with Mogami over the last few months. I ordered tons of cables in many lengths from Redco. I believe it's good to know what's possible using very popular but inexpensive cables. <br />
      <br />
      The only thing really new for this review was the TRS terminations. <br />
      <br />
      Please note that during the review I also used all kinds of other cables from Kimber, AudioQuest, Wire World, etc...<br />
      <br />
    1. demondog's Avatar
      demondog -
      As an m903 owner, I've been waiting for your impressions of this product since you first mentioned you were going to do a review. I look for as many opinions as I can, and find them all interesting. Good job pointing out the features, flexibility, and high quality of this headphone amp/DAC. I've been using it as the pre-amp/DAC in my main speaker based system, as well as using it for occasional headphone listening, for several months. Prior to this I was using the m902. The capabilities of these units are hard to beat, though the m903 is considerably better both sonically and functionally.<br />
      <br />
      I appreciate the forthright opinions in the review, but was a little surprised at the perfunctory headphone section of the review, considering the Grace m903 is primarily a headphone amplifier as indicated on the front of the unit. I can't remember where, but I recall reading an offhand comment from Grace indicating that the line output devices are not of the same quality as the headphone output. I have confirmed they do use different output amplification devices.<br />
      <br />
      It doesn't negate your impressions at all, but putting your primary review focus strongly on what might arguably be considered the secondary function of a product is something to be considered when looking at the review in general.<br />
      <br />
      I can not agree or disagree with your judgment of the sound of the m903 through the line output. Though it sounds very good to me, I have not compared it with other similar high end pre-amp/DACs, but I trust that your comparison to the three times as expensive Berkeley Audio Design Alpha DAC Series 2, and to your memory of the Bel Canto DAC 1.5 were honest assessments. At least I can take comfort that you preferred the m903 over the Benchmark DAC1 HDR, which I also considered buying at one time.
    1. barrows's Avatar
      barrows -
      Please, do some homework before making claims:<br />
      <br />
      "As for the actual topic, the Grace DAC seems to be just another of the many pretty high priced 'run-of-the mill' DACs, rather similar to the Benchmark, which I have seen described here as both very good and 'godawful'. The chips in all these things are much the same, as I have said."<br />
      <br />
      High priced? At under $2K, with a feature set which eclipses the dCS Debussy (their entry level product at $13K), I would not consider the Grace high priced. This is a high quality piece of audio gear, with many features, and is made in the US as well.<br />
      <br />
      The Grace actually includes quite a bit of discrete topology, proprietary, circuit designs, including a discrete I/V converter and output stage. It is not at all similar to the Benchmark products in this way (which I would say are an example of a DAC which is just chips in a box). BTW, speaking specifically of only DAC chips themselves; they are hardly "much the same" as you claim-for instance, the ESS 9018 DAC chip actually has more in common with the design of dCS' Ring DAC, than it does with TI 1794 DAC chip, or a Wolfson 8741 DAC chip, and a TI 1704 is a multi bit, R2R design DAC, completely different in topology from the ESS 9018, TI 1794, or Wolfson 8741. Even if a manufacturer does choose to use an IC DAC chip, there are choices to be made, and implementations to be developed.<br />
      <br />
    1. Radio Jimbo's Avatar
      Radio Jimbo -
      I've owned the Grace 903 for 2 months, and think it's a remarkable DAC. I've owned 3 iterations of the various Benchmark gear, and find the Grace superior in every way. In my own system the 903 is highly resolving both as a pre for my Mac mini based server and as a headphone amp. No one's taste, hearing, equipment and room acoustics can ever be identical, and Chris in his review made the point several times that any potential listener should actually AUDITION the piece before making a decision. No offense intended, but I think it's goofy to read a single review and then say "I'm not going to buy this now". Audio isn't baseball, unless you have the wealth of George Steinbrener. I bought my 903 for $1500, and like it a lot. That doesn't mean it's fair to compare it to a $5000 piece of gear. sheeze. Try one out, you may actually find what you're looking for. Or not. It's the thrill of the hunt.....