I have reviewed the Grace Design m900 for Positive Feedback Online.
- The m900 is built around AKM's latest-generation 4490 chipset, which features 32-bit processing, and supports sample rates up to 384kHz PCM or 256X DSD. The m900's four selectable digital-reconstruction filter settings are very rare at this price point, the options being, sharp or slow roll-off, and linear or minimum phase.
- In order to minimize jitter, the m900's USB interface operates in asynchronous mode, allowing the m900 to be the master clock. In addition to USB, the m900 has S/PDIF coaxial and Toslink optical digital inputs.
- The m900 can operate from USB power from the host device, or from an external power supply (provided). The High-Power supply is especially helpful when listening to difficult-to-drive headphones.
- Made in the USA, with a transferable 5-year warranty.
In my experience, for $660, you can't beat it with a stick.
BTW, the photo is from a German review. I liked the photo very much; but it is not in my review, for the usual reasons.
ciao,
john
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We don't know much about your experience. Maybe it would help if you could fill-in a little more 🙂
Hi, Mark.
Well, you asked!
I have been making recordings since 1968 as an amateur recordist, and since 1982 as a professional producer. For most of my commercial releases, Bob Ludwig, who made the "Hot Cut" of Led Zeppelin II, has been my mastering engineer. We still swap emails a couple of times a month. I have been in Bob's mastering studio many times.
I also was given the privilege of hearing the original unedited backup safety master tapes of Kind of Blue at Sony Music Mastering. I also gave a presentation at an academic conference hosted by Yale Music School.
Music I produced was used in a Hollywood major-studio No. 1 box-office feature release (Heartbreakers) and in the No. 1 daytime drama series (The Young and the Restless). And lots of less-august places.
My series of classical-crossover Christmas string-quartet CDs has been a reliably strong seller for Steinway for many years, and you can listen to it here, for FREE!
I don't post family pictures to the internet, but I worked on one concert with John Williams of the Boston Pops, and he kindly consented to be photographed with my son. At Brown University, I was a violin student of Professor Kowalski, which means there are only three people shaking hands between Tchaikovsky and me. I once and only once played on a real Stradivari.
One of my mentors in art and in life was Boris Goldovsky, of the Metropolitan Opera. Much later in life, I produced the last recording made by Met soprano Kaaren Erickson, who died tragically young just as the CD was released.
I am best known for producing Arturo Delmoni's Songs My Mother Taught Me, the violin encore-piece album best known to audiophiles. Here's Arturo rehearsing with Steve Martorella for a recital I presented.
Songs My Mother Taught Me in its Bob Ludwig digital remastering was last year reissued in an IMPEX "Glass & Gold" optical-glass gold CD, for $1200. The signed numbered limited edition sold out.
For 26 years I was a visiting lecturer at Thomas More College in New Hampshire. I organized and presented the chamber-music series, presenting live performances by world-class artists such as Nathaniel Rosen and Peter Sykes.
I wrote for a few years for Harry Pearson of The Absolute Sound; I then voluntarily left to write for Stereophile, where I was for nearly 20 years before voluntarily retiring to pursue my own work in cable and loudspeaker design.
I have heard very expensive DACs in my own system from Playback Designs, dCS, msb, and Bricasti. And lots of more-afforable DACs.
Despite all that, I STILL need to keep a "Cheat Sheet" on my music stand, of Relative Major and Relative Minor Keys. Because I can't count.
And, whenever I begin to sing, be it French Art Song or Lieder or Opera, my pre-schooler (late-in-life) daughter yells, "DADDY NO SING!!!"
Those who cannot do, teach. Those who really cannot do, become record producers.
And the truly desperate ones become High End Audio Journalists. tee hee.
If anyone is interested, I can email a CD-quality version of my Producer Reel, as well as a Titles Sheet.
Oh! My current hi-res project, in a low-res iPhone clip:
How's that?
all my best,
john
Well, you asked!
I have been making recordings since 1968 as an amateur recordist, and since 1982 as a professional producer. For most of my commercial releases, Bob Ludwig, who made the "Hot Cut" of Led Zeppelin II, has been my mastering engineer. We still swap emails a couple of times a month. I have been in Bob's mastering studio many times.
I also was given the privilege of hearing the original unedited backup safety master tapes of Kind of Blue at Sony Music Mastering. I also gave a presentation at an academic conference hosted by Yale Music School.
Music I produced was used in a Hollywood major-studio No. 1 box-office feature release (Heartbreakers) and in the No. 1 daytime drama series (The Young and the Restless). And lots of less-august places.
My series of classical-crossover Christmas string-quartet CDs has been a reliably strong seller for Steinway for many years, and you can listen to it here, for FREE!
I don't post family pictures to the internet, but I worked on one concert with John Williams of the Boston Pops, and he kindly consented to be photographed with my son. At Brown University, I was a violin student of Professor Kowalski, which means there are only three people shaking hands between Tchaikovsky and me. I once and only once played on a real Stradivari.
One of my mentors in art and in life was Boris Goldovsky, of the Metropolitan Opera. Much later in life, I produced the last recording made by Met soprano Kaaren Erickson, who died tragically young just as the CD was released.
I am best known for producing Arturo Delmoni's Songs My Mother Taught Me, the violin encore-piece album best known to audiophiles. Here's Arturo rehearsing with Steve Martorella for a recital I presented.
Songs My Mother Taught Me in its Bob Ludwig digital remastering was last year reissued in an IMPEX "Glass & Gold" optical-glass gold CD, for $1200. The signed numbered limited edition sold out.
For 26 years I was a visiting lecturer at Thomas More College in New Hampshire. I organized and presented the chamber-music series, presenting live performances by world-class artists such as Nathaniel Rosen and Peter Sykes.
I wrote for a few years for Harry Pearson of The Absolute Sound; I then voluntarily left to write for Stereophile, where I was for nearly 20 years before voluntarily retiring to pursue my own work in cable and loudspeaker design.
I have heard very expensive DACs in my own system from Playback Designs, dCS, msb, and Bricasti. And lots of more-afforable DACs.
Despite all that, I STILL need to keep a "Cheat Sheet" on my music stand, of Relative Major and Relative Minor Keys. Because I can't count.
And, whenever I begin to sing, be it French Art Song or Lieder or Opera, my pre-schooler (late-in-life) daughter yells, "DADDY NO SING!!!"
Those who cannot do, teach. Those who really cannot do, become record producers.
And the truly desperate ones become High End Audio Journalists. tee hee.
If anyone is interested, I can email a CD-quality version of my Producer Reel, as well as a Titles Sheet.
Oh! My current hi-res project, in a low-res iPhone clip:
How's that?
all my best,
john
John,
Thank you. Guess I would just say its not clear that this is the best part of the forum for this type of content. We usually focus more on the deeper technical details involved in designing our own dacs. Some of us have designed with AK4490, AK4493, AK4499, as well as other parts. From that perspective, that m900 uses a 4490 already says a lot. Knowing that m900 can operate on USB power says a bit more about its design. Other than a few details like those, there isn't much to chew on. No hi-res pics of the PCB so we can read part numbers on the chips, etc.
If I could make a recommendation, it might help if you could customize content a bit depending on where you would like to share? Maybe its kind of like how people are sometimes advised to customize resumes for each prospective employer. Might make for a better fit and for more interest on the part of a particular group demographic, is all I'm thinking.
Best,
Mark
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Hi All,
I saw this and though I would post a tech article about the m900. It does not get in to the nitty gritty detail but gives an overview of the design attributes. Feel free to ask me questions!
Cheers,
Michael
I saw this and though I would post a tech article about the m900. It does not get in to the nitty gritty detail but gives an overview of the design attributes. Feel free to ask me questions!
Cheers,
Michael
Mark, given how many electrons you wasted over the years harping on about how good your benchmark DACs were you are in no position to tell other poster they are in the wrong place. This thread is on topic. period!
Also I think you owe John an apology for doubting him AND being too lazy to check his posting history before coming on all high and mighty...
Looks like a pic was posted in another forum:
Most of the part numbers are unreadable, but there appears to be a TPA6120A2 HPA chip.
https://www.ti.com/lit/ds/symlink/t...ttps%3A%2F%2Fwww.ti.com%2Fproduct%2FTPA6120A2
Hmmm, only see one clock over there by the XMOS chip. Also, there is a PLL rather than an ASRC for TOSLINK?
Most of the part numbers are unreadable, but there appears to be a TPA6120A2 HPA chip.
https://www.ti.com/lit/ds/symlink/t...ttps%3A%2F%2Fwww.ti.com%2Fproduct%2FTPA6120A2
Hmmm, only see one clock over there by the XMOS chip. Also, there is a PLL rather than an ASRC for TOSLINK?
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Hi, Mark,
Ah, thanks for your perspective.
I hope it is apparent to you that I took your question to mean, "OK, why should we trust John Marks's conclusions as to, what the Grace Design m900 SOUNDS LIKE in general; and specifically, compared to other entrants into that market?"
If that had been the intent of the question, then I do think that I provided enough verifiable information that people should be able to some extent at least, "Trust John's Ears." Merely as one anecdotal data point; but not worthless, either.
I of course understand that this is a DIY Audio Forum... DUUH, Daddy. However, in posting, my assumption was that someone who, like myself, is a DIY Loudspeaker builder, might appreciate a suggestion as to an excellent affordable DAC.
BTW, I forgot to mention a couple/few things.
1) I have never heard Merging Technologies digital gear in my home system, but I have heard it at one of my recording sessions. Amazing. But nobody ever called Merging Technologies gear "Budget" or "Affordable."
2) I neglected to mention home auditions of Accuphase and Esoteric digital gear, both of which I covered in Stereophile magazine.
3) My JMR recording of Nathaniel Rosen's JS Bach solo-cello Suites was in-flight music on US Presidential aircraft Air Force One. You can't ask for that; they have a consultant who decides. However, that was during the Clintonian Captivity, so, who can imagine what depravities that music was the soundtrack for? I later received a literal engraved invitation to attend the Grammy award ceremony. But, they wanted a hefty donation, and I never expected we would win. (Obviously, we did not win.)
FINALLY, it is not clear, at least to me, whether you clicked over to read the full review over at Positive Feedback Online.
I don't care about clicks--AFAIK, PFO does not count clicks on specific articles.
But I do want as many people as possible to read about (and listen to) my recommendation of Kate St. John's first solo album, Indescribable Night. It's really something!
ciao,
john
Hi Bill, As I have said before my opinions are subject to updating over time as new information becomes available. Apparently I am not alone in that regard:
https://www.ft.com/content/76e6fae7-f273-49e6-8238-288d9e4991c7
Regarding the thread content, I think its getting more interesting than it was. Do you disagree?
Thanks, but, I was not offended by Mark's post. I though it was a bit nerdy, and erm, perhaps we could say "Overly Focused"?
But I did not get a vibe that Mark doubted that the m900 sounded at least respectable.
I also know that my tastes are not everybody's tastes. It's like the five blind men in the folk tale, each one feeling a different part of the elephant.
I was at a record-dealer's national convention, and a Tower Classical Department manager came up to me after my presentation. I already knew that he was a Juilliard grad who had opted for a steady paycheck. He warmly said, "John, you really listen like a real musician listens!" (I don't think he knew that I had studied violin at the college level, though of course I did not major in it--you cannot do that at Brown!)
Awww, such a nice thing to say.
HOWEVER, a very experienced conductor once said to me, "John, you listen like a violinist!" And he meant that as a criticism. I did not pay enough attention, it seemed to him, to the whole picture. I was fixated on the harmonic structure of the string overtones.
GUILTY AS CHARGED.
all my best,
john
PS: Years back I compared Grace Design's then offering in that class and price tier to what Benchmark was then offering, and my clear preference was for Grace Design. Benchmark was so annoyed that they circulated a White Paper erm, trashing my writing. I am sure John Atkinson recalls that episode. He was annoyed--but I don't want to get down into the sandbox and talk about what upset him. Let's move on!
I did. Noticed you mentioned that the m900 is bargain priced for what you get, but its not as good as the Bricasti that costs a lot more. That's fine.
Also, I understand that making something like this that can sell at its price point involves a lot of engineering effort. Anyway, I'm not complaining, I'm just interested in how it works.
Moreover, I know my post was a bit provocative. It it wasn't I don't think this thread would be getting a much attention as it is. Not necessarily a bad thing.
Mark
Hi Mark,
The m900 uses the Cirrus CS2100 clock synthesizer. This acts as a master clock for both USB asynchronous frequencies as well as a PLL for the SPDIF and TOSLINK. The SPDIF/TOSLINK signal is decoded in software in the XMOS then the recovered clock is re-clocked by the CS2100. No resampling going on.
Cheers,
Michael
Not surprised. Back when I got the Benchmark DAC-3, I believed a lot more in typical figure-of-merit measurements of audio equipment than I do now. At one time people who questioned the value of such measurements around here could catch a lot of flack. Talking about how a piece sounded without providing 'proof' by way of measurements would too often be dismissed as imagining things that aren't real. Of course that's not to say that people never imagine things, but that's not the whole story of how aural perception works, particularly in the case of very experienced/expert listeners.
To move along here without going too far off topic, I wonder if anyone would like to express an opinion of m900 reproduction of the stereo illusion of soundstage? Width, depth, spatial localization of performers in the virtual soundstage. That sort of thing. This of course assumes m900 is being used as a dac to drive speakers in a room. Reason I ask is because its something that can be hard to do well, and IMHO its something not that's maybe so easy to measure with typical test instruments. However, it is something is important to at least some subset of music listeners.
Turns out I have a few purely technical questions about m900.
The first is whether the Windows driver supports ASIO and or WASAPI Exclusive Mode?
The second is if using the DAC with the line outputs, if it is possible to put AK4490 into DSD Volume Bypass mode (a feature Topping made available for D90 dac)?
The third question is whether or not DoP is supported?
Separately, and as a non-technical question, I would like to know if any of John's listening tests involved using M900 in DSD256 mode?
As a side comment I would note that the link in the owner's manual to the Windows driver appears to be out of date.
The first is whether the Windows driver supports ASIO and or WASAPI Exclusive Mode?
The second is if using the DAC with the line outputs, if it is possible to put AK4490 into DSD Volume Bypass mode (a feature Topping made available for D90 dac)?
The third question is whether or not DoP is supported?
Separately, and as a non-technical question, I would like to know if any of John's listening tests involved using M900 in DSD256 mode?
As a side comment I would note that the link in the owner's manual to the Windows driver appears to be out of date.
Hi!
The Windows driver (XMOS branded Thesycon software) supports ASIO and WASAPI in Exclusive mode.
We do not have a setting to bypass the volume control in DSD mode. That is something we could look for a future firmware update.
The m900 only uses DoP for DSD playback.
Best,
Michael
The Windows driver (XMOS branded Thesycon software) supports ASIO and WASAPI in Exclusive mode.
We do not have a setting to bypass the volume control in DSD mode. That is something we could look for a future firmware update.
The m900 only uses DoP for DSD playback.
Best,
Michael
Hi Michael,
That's good to know. The other thing may be good to put in the owner manual would how to best configure the dac for PCM. By default, if not using WASAPI Exclusive Mode, Windows will resample the audio stream as needed to make it the same as the 'default' sample rate property in the sound settings for the device. The real-time resampling isn't the best, so better to avoid it if possible. Also, if Windows has assigned the sound device as 'default sound device' and or 'default communication device' then Windows may even resample PCM streams over ASIO (default device assignment is indicated by a green circle with a white checkmark inside it as seen in the control panel sound settings). Moreover, Windows will often reassign default devices after a Windows Update and or of the sound device is plugged into a different USB port. Use of player apps that support WASAPI Exclusive Mode should prevent unwanted resampling. Attached below is a screenshot showing the default sample rate setting.
Best,
Mark
EDIT: It turns out some people have a strong preference for the sound of high sample rate DSD (DSD256 or higher). As a result more player apps are including software PCM->DSD modulators. Roon has that feature, and IIRC JRiver also offers it. Of course the most well known software among audiophiles is HQ Player. For those people who prefer that sound, DSD volume bypass mode may give a better result. IIRC for D90, Topping called the mode with volume control 'preamp mode.' The mode without volume control and with DSD volume bypass was called 'dac mode.'
That's good to know. The other thing may be good to put in the owner manual would how to best configure the dac for PCM. By default, if not using WASAPI Exclusive Mode, Windows will resample the audio stream as needed to make it the same as the 'default' sample rate property in the sound settings for the device. The real-time resampling isn't the best, so better to avoid it if possible. Also, if Windows has assigned the sound device as 'default sound device' and or 'default communication device' then Windows may even resample PCM streams over ASIO (default device assignment is indicated by a green circle with a white checkmark inside it as seen in the control panel sound settings). Moreover, Windows will often reassign default devices after a Windows Update and or of the sound device is plugged into a different USB port. Use of player apps that support WASAPI Exclusive Mode should prevent unwanted resampling. Attached below is a screenshot showing the default sample rate setting.
Best,
Mark
EDIT: It turns out some people have a strong preference for the sound of high sample rate DSD (DSD256 or higher). As a result more player apps are including software PCM->DSD modulators. Roon has that feature, and IIRC JRiver also offers it. Of course the most well known software among audiophiles is HQ Player. For those people who prefer that sound, DSD volume bypass mode may give a better result. IIRC for D90, Topping called the mode with volume control 'preamp mode.' The mode without volume control and with DSD volume bypass was called 'dac mode.'
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May as well take a moment to describe my experience with certain Grace Design products. Attached is a pic of two preamps I have had for a long time and intend to keep.
They are very clean mic/instrument preamps that can even be used for FFT notch filter makeup gain (particularly the older model 101 with the chrome front panel). Also they can be used as colored preamps by using them to drive various output transformers, such as a Sowter clone of an old Neve output transformer. These preamps are even good for something like a vintage electric guitar mic preamp type sound if used that way.
IOW I have had some good experience with Grace Designs, is all. That said, have never heard an m900 so no opinion here for that device. All the forgoing said in the interests of disclosure, nothing more.
They are very clean mic/instrument preamps that can even be used for FFT notch filter makeup gain (particularly the older model 101 with the chrome front panel). Also they can be used as colored preamps by using them to drive various output transformers, such as a Sowter clone of an old Neve output transformer. These preamps are even good for something like a vintage electric guitar mic preamp type sound if used that way.
IOW I have had some good experience with Grace Designs, is all. That said, have never heard an m900 so no opinion here for that device. All the forgoing said in the interests of disclosure, nothing more.
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Wow! A silver and black 101! Nice.
Thanks for the "disclosure".
And thanks for the suggestions on the manual. We have not touched that document in some time. Time for an update.
Thanks for the "disclosure".
And thanks for the suggestions on the manual. We have not touched that document in some time. Time for an update.
This has nothing to do with the M900 but Grace is over in Lyons, Colorado, which is not far from Boulder. I would love to be back there. Good, intelligent folks permeate the area (and they have some pretty killer pinball).