Sound Galleries SGM 2015 Music Server

Device Type: Music Server
Input: Ethernet, USB (storage), 2x DIN (Mouse and Keyboard)
Output: USB (DAC), 3x Video
Dimensions (W x D x H): 16 1/2 x 19 x 7"
Weight: 85lbs.
Availability: through Authorized dealers
Price: $16,000.00

You Know Who You Are
To my mind, there will be three main types of response to this review:

  1. $16k for a computer? Are you nuts?
  2. I wonder if I can get a large % of this performance for a lot less $
  3. I'd like to listen to the SGM in my system
My guess is you know who you are before reading any further.

The Back Story
Munich High End 2015 introduced me to Sound Galleries and their room which featured gear from Lampizator, Audiopax, and Avante Garde, cables from Tellurium Q, and "...a custom Windows 10-based PC with SSD's running off battery power using HQ Player to convert everything to DSD." My report on this room was a rave, "The fact that I found this room, sponsored by Monaco's Sound Galleries, to be a few steps beyond most every other in terms of natural musicality speaks to all the parts that make up the whole. Rarely have I experience a similar sense of immediacy, flow, and effortlessness. You know like real music."

One of the outcomes of that experience is the full loom of Tellurium Q cables sitting in my system. Another outcome, from the Sound Galleries perspective, was an interest in refining their music server and turning it into a commercial product.

This commercial product, the Sound Galleries SGM 2015 Music Server, is sitting on my equipment rack and is the subject of this review.

The SGM 2015 Server
I'm going to leave the heavy list of attribute lifting to Sound Galleries:


  • Processor: Intel Skylake i7 6700K
  • Memory: 16 GB DDR4
  • SSD: 1TB
The Sound Galleries Solution
  • Custom designed hardware for low RF noise and CPU timing precision, with fanless CPU cooling
  • Custom optimised operating system to deliver low RF noise during computer operation and computational timing precision
  • Roon, best in class software for library management, Tidal streaming and user interface
  • HQP Player, best in class software for upsampling and format conversion to DSD 512
Reducing RF Noise
  • Steel potted transformer with copper foil isolation between primary and secondaries
  • Cree Schottky rectifiers
  • Two 3.6 kg choke filters delivering microvolt ripple
  • 660,000 microfarads of Audiophile Grade capacitors from Mundorf
  • Fanless CPU cooling, motherboard’s RF noisy PWM fan control is disabled
  • Independent power supply for SSD
  • Optimized RAM with vibration control
Fanless Cooling of CPU
  • Custom 4 heat pipe diamond polished copper CPU cooler block with individual pipe clamps
  • Custom finned heat sinks CNC machined from solid copper billet
  • Ample cooling capacity for the overclocked CPU
Motherboard Timing
  • Standard CPU and mobo chipset timing is derived from a crystal clock that costs about 1 Euro, and has a frequency stability of 50 pp million, which is replaced by:
    • OCXO - oven controlled crystal oscillator
    • Custom cut and manufactured for Sound Galleries in the USA, with 5 pp billion frequency stability and low phase noise at low frequencies
    • Custom designed OCXO signal electronics and dedicated power supply from suppliers in Holland and Sweden
  • OCXO Sound quality difference - a pristine clarity with no glare or edginess
SGM Windows 10 Custom Build
  • All Microsoft phone home and logging removed
  • Functional IE 11 for downloading content and USB drivers
  • Headless control and remote access for worldwide online support
  • Whole Windows OS occupies less than 5GB
HQPlayer Optional Upsampling and Format Conversion
  • Look ahead elimination of artifacts which were created during the original analog to digital conversion
  • A variety of intelligent interpolation methods to create new image samples
    • Different choices for pre and post ringing, phase distortion, and computational intensity
  • Sigma Delta Modulation—creating the 1-bit stream at up to DSD512
  • Choice of 5th order and 7th order modulators
  • Adaptive modulators available
HQPlayer DSD64 to DSD512 Process
  • Direct rate conversion with high frequency noise removal
  • Re-modulating the signal at 24 MHz using HQ Player’s 5th or 7th order modulators
  • Choice of Integrator
  • Note - SACD’s are only DSD 64 and using 3rd or 5th order modulators
SGM As Bit Prefect Transport
  • Combining Roon interface convenience with delivery bit perfect data over USB
  • Optical fibre isolated AES interface available as an option for up to 24 bit / 176 and 192 KHz

Comments on The List
The list is not complete. Speaking to Edward Hsu of Sound Galleries, I think it's safe to say that every single solitary aspect of the SGM server was examined, tested, and refined, in some cases over and over again, before being signed off on—cost no object. It is also fascinating to hear Edward talk about the process and understanding what changes had real impact on sound quality since a number of items on that list don't seem to belong there on first blush.

While some people, you know who you are, would certainly be interested in this longer conversation, that is the subject for another day (and perhaps best captured in video). Today, we are here to talk about what the Sound Galleries Music Server makes us hear.

I find the SGM's build quality tickles my fancy with its rugged simplicity. It looks the part. While there is 1TB of SSD on board, I played all music from my Synology 412+ NAS and streaming from Tidal HiFi. Owners can also opt to directly connect USB storage. I used the VNC Viewer app on my Mac to load up DAC drivers and change HQPlayer settings. The SGM starts up and shuts down in seconds (how un-Windows-like).

Since the SGM comes with Roon, a very wise move imo, that's what I used to control playback. My system remains the totaldac D1-six DAC, Ayre AX-5 Twenty integrated amplifier, and the DeVore Fidelity gibbon X all wired with Tellurium Q Black cable.

In my system and barn, the addition of the SGM 2015 Music Server moved my music playback into the realm of impeccable. I do not take that word lightly and use it with some trepidation because I have not heard everything. With that being said, what I can say is that my system has never sounded better and the results I'm getting in-barn make listening to other systems somewhat of a let down.

The main areas of improvement over my every day system, which employs the sonicTransporter i5 (sT) and microRendu (mR), revolve around—to borrow a favorite phrase from Heidegger’s essay "The Origin of the Work of Art"—"the thingness of the thing".

Music fills my space with a you-are-thereness that heretofore has more or less been hinted at. While the sT/mR combo give me a large percentage of what the SGM offers, this added percentage brings music playback into the realm of the real.

I recently had a few friends over for a listening and barn orchestra party. John DeVore and Stephen Mejias arrived just before noon and we spent the better part of the day into the early night listening to, and at times playing along with1, music from the system. We took turns selecting the music, letting each others selections inform our own (this is a boat load of fun). John queued up The Ensemble Of Irreproducible Outcomes' "Intonazione/The Foggy Dew" while he was sitting in the red chair and after a few minutes he suggested, strongly, that Stephen take the hot seat. After some time, Stephen suggested, strongly, that I take his place.

Let me put it this way—if you come over to hang out in the barn and I want to blow your music-loving mind, I will play The Ensemble Of Irreproducible Outcomes' "Intonazione/The Foggy Dew". This is very well recorded acoustic music and the space of the recording becomes the space of the barn: In every way, shape, and form. Every aspect of reproduction including tone, texture, dimensionality, attack, decay, and space in every dimension is seemingly 100% there. I say seemingly because ya never know but in my experience my system with the SGM is 100% as in, I have not experienced better.

You know who you are. The sT/mR combo, even with the Uptone power supply adds up to a rounded up $1700, making this comparison rather...silly? I typically try to have like-components in for review so I can offer a price-wise comparison but this wasn't possible here for a number of reasons, the least of which being I'm not aware of other servers in this price class. I have reviewed a number of other well-regarded servers including the Antipodes Reference Series DX, Aurender N100H, a number of the SOtM products, and various and sundry others. While a direct comparison is not possible seeing as none of these other servers are here and I did not review every one of them with my current system setup, I can say I've never heard my system, or many others, sound like this.

I mostly listened through my totaldac D1-six but I also spent some real time pairing the SGM with the mighty T+A DAC 8 DSD (see review). That combination allowed me to have HQPlayer upconvert all incoming data to DSD512 before the DAC 8, something that turned a fine DAC into a mighty fine DAC. If I owned the T+A DAC 8 DSD, I would not rest until I heard HQPlayer do its thing. Speaking to Jussi Lasko, the man behind HQPlayer, this process, the upconvert to DSD512, requires lots of processing horsepower, "For upsampling to DSD512 for the T+A DAC8 DSD, the Core i7 6700K used also in SGM 2015 is a good CPU baseline without much restrictions for possible HQPlayer settings."

With my totaldac, I mainly stuck with the HQPlayer settings recommended by Edward Hsu (as pictured). I did not spend a great deal of time changing these settings because they sounded the best after some experimentation and I was more interested in just listening to as much music as I possibly could before sending the SGM on its way. I will say this—HQPlayer is an outstanding product and for its current asking price of $138.82 it is also a crazy-assed bargain. I know of no other way to improve the performance of a DAC that comes close. Of course you need to account for the cost of the machine to run it on...

I listened to my system with the Sound Galleries SGM server for months, which adds up to hundreds of hours of listening time and lots and lots of music. Switching back to my sT/mR combo, which took all of a minute or so, was not a huge letdown. Changes included flabbier bass, less tonal variation, less precise sound location, less precise sound image, less depth, less height, less width, and generally music sounds a bit homogenized from track to track. There was sameness to the sound of music and things were a bit wilder and a bit woollier, which reduced the heights of emotional connection, and the sheer joy, of listening to lots and lots of music.

I have two more things to say; 1) up until the SGM, I was of the opinion that expensive music servers were a thing of the past because they did not offer much of an improvement, if any, over less expensive options, and 2) I was wrong.

You Know Who You Are
If you were a #3 (I'd like to listen to the SGM in my system), I'd agree—you want to hear the Sound Galleries SGM 2015 Music Server in your system. Sound Galleries offers "qualified buyers" in Europe, North America and Hong Kong a home demo.

If you were a #2 (I wonder if I can get a large % of this performance for a lot less $), I'd recommend starting with HQPlayer. If you were a #1 ($16k for a computer? Are you nuts?), I'd suggest you may have just wasted your time ;-).

1. the barn orchestra instruments include 4 guitars (2 acoustic 2 electric), a blackface Princeton Reverb amp, various effects pedals, a baritone ukulele, a toy accordion, a Farfisa (Pianorgan I), a cowbell, a slide whistle, sticks, brushes, a trumpet, a talking drum, and a Cojon.

Also in-use during the SGM review: totaldac d1-six, T+A DAC 8 DSD

Associated Equipment

otaku's picture

(4) All of the above

bobflood's picture

the best DSD and the best PCM comparison possible with your DAC and the T+A DAC.

How did they compare? Differences on the same music?

Thanks Michael,


Michael Lavorgna's picture a not-narrow margin.

I'm not sure I'd frame this as DSD v PCM, rather DAC v DAC. Attribution is a tricky business and we need to take all aspects of DAC design into consideration, imo.

bobflood's picture

What I was getting at is that you had a true R2R PCM DAC and a true DSD 512 Delta/Sigma DAC. Very different ways to get sound.

miguelito's picture

Sounds fantastic. I would say it's a good solution if you want both HQP upsampling and in-the-box support (and you can afford it).

As for the DAC question, I thought that my DAC (EmmLabs XDS1v2) sounded more nuanced and musical than the T&A (but then again my DAC is $25k). Ed played a few redbook Miles Davis live tracks from TIDAL upsampled to DSD512 into the T&A, and that was good, but still less musical than the EmmLabs.

stevebythebay's picture

Seems that the Aurender W20 and Baetis Ref. 2 are in the same price category. And the former has received top reviews from numerous sources. And I find it curious that the output appears to be so restricted. And 1TB of SSD appears quite limited if intended to house a music library, and overkill if not. All in all, now that we're in 2017 I suppose 2015 in the name tells you this is due for an update -- especially for the price.

EuroDriver's picture

The SGM is Roon feeding HQ Player centric. The weight and cost of the SGM is to allow HQ Player's most computationally demanding filters and modulators for PCM to PCM, PCM to DSD, DSD to DSD, and DSD to PCM processing.

We have limited the output option to USB, as DXD and DSD 256/512 are only supported over USB. We do have excellent USB to AES/BEU solutions available for interfacing the SGM with non USB DAC's

There are 2TB and 4TB SSD options. For larger library's we recommend a NAS solution

We don't expect there to be many top draw DSD 1024 DAC's in the future as there are significant implementation difficulties with low jitter clocking at 44 MHz, and the theoretical benefits of DSD 1024 are questionable. We are therefore confident that the SGM will not be obsolete for many years to come. Our investment in the casework reflects our conviction that the SGM will provide many years of reliable service.

As to the sound quality, a home demo will determine if the SGM is right for you

stevebythebay's picture

Given my use case: No DSD, just a Berkeley Alpha USB to Berkeley Ref. DAC this specific solution is not really applicable. And my current top end MacMini running Roon core and with USB attached 5TB drive running Ethernet out seems to be doing quite nicely. However, if a system comes along that's designed as a no holds barred music player to output either Ethernet or (heaven forbid) USB, I'd consider giving it a go an dropping my microRendu/Sonore Signature LPS as well.

The Federalist's picture

I do appreciate the ways you went a big step above the typical server with separate trafos for power and a separate pcb with an oven controlled clock. Thats pretty cool. Kudos for doing it right, versus just grabbing $700 of off the shelf parts and shoving it inside a bling case and asking $10K.

One thing I am curious about, and this always gets in the way of me spending big money on a dedicated audio computer. Is the long term support for the Asus B150M motherboard, the skylake CPU and 1151 chipset.

In general these MB have and related components have a 5 year service life before you start seeing issues with instability and rarely do you see support stretching out much further than 7 years from either ASUS.

Does SGM have a plan in place to support customers who drop this kind of money on a computer for long term support?

The obsolescence life cycle in the computer world is my stumbling block with spending big money on a dedicated audio PC. Curious if you guys are addressing that are forced by certain parts into the same cycle.

EuroDriver's picture

The longevity of the SGM 2015 is something we have thought about quite a lot about. We do feel that as far as computational horse power needed for 2 channel PCM and DSD, we have hit a plateau for a while. The advantages of going to DSD 1024, are not obvious to us, there seem to be more drawbacks of 44 MHz data stream, challenges of jitter control and the quantum of ultrasonic noise than the theoretical advantages.

Where we do see developments and improvements is in the playback software. With both Roon and HQ Player, improvements are coming thick and fast. The SGM being the most powerful server on the market, has absolutely no problem to run the new versions for many years to come, and when more horsepower is needed, then a motherboard swap is relatively easy. The nice thing about using a Micro ATX board is that future M-ATX boards can drop right in, even the mounting holes are in exactly the same place ! We will need to install a new back plate, but we manufacture the back plates in house, so easy to do, and low cost for us

As to reliability, the key driver is heat dissipation, and operating temperature. The cooling design has been very over specified, and we don't expect to see any thermally caused shortening of the SGM's service life which we project to be in excess of 8 years.

The Federalist's picture

That's exactly what I was looking for.

DH's picture

Wish I could afford one. That will never happen.

I will just have to make do with my fanless i7 PC server with Linear PS, mRendu, LPS-1, and SOtM Lan Filter. All of that together approaches $4500, Which most people, even audiophiles, think is pretty expensive.

To think that an "upgrade" to that is almost 4X that price is pretty mind boggling.

Part of me hopes one day to hear such a setup. On the other hand, I think my setup sounds great. Do I want to hear something like that and think mine is second rate...always a problem of the audiophile.

Hope you still fully enjoy your system when the SGM goes away.

Great review, by the way. Very well written and you hit all the important points, IMO.

Michael Lavorgna's picture
...still sounds great, just not as great ;-) One of the hazards of the job. Thankfully I've found that when listening for pleasure, I can easily focus on the music and not think about comparative listening.
Boogieman's picture

Thank you for a great review. Maybe I misunderstood, but does everything need to go to DSD with this product? or can things stay in PCM?

For less technically inclined, why don't the DACs do what HQPlayer does?

Did you use MQA Tidal, or plain old Tidal?

And also, how does one figure out the appropriate settings for each DAC to perfectly jive with this product? Is it art or science? If art, can one flavor to taste?


Michael Lavorgna's picture
You can send out all files in their native format/resolution.

The answer to your second question is there are many reasons. One of the main reasons being most DACs do not have the processing power to run all of the features that HQPlayer offers, especially if you upconvert to DSD512 and doing any kind of DSP. Another reason is some people feel that having this kind of heavier lifting processing going on *outside* the DAC allows for better performance *within* the DAC. If you watch the video conversation with Juergen Reis, he gets into this a bit.

I used Roon exclusively which does not yet offer Tidal/MQA.

Art. As mentioned, Sound Galleries offers this 'artful' matching service, if you will, when you purchase the SGM server. Lastly, yes - there are a number of settings in HQPlayer which allow you to flavor to taste.


DH's picture

No, it doesn't have to go DSD, but that's the best way to exploit HQPlayer and especially the T+A DSD 8, whose "native" internal rate is DSD 512. HQP also does a great job with PCM, but it's even better upsampling and converting to DSD.

DACs don't do what HQP does for 4 reasons: a) a computer, especially an i7, has orders of magnitude more computing power than the chip in any DAC; 2) as a result of 1, the PC can do upsampling and filtering on the fly that is too much for a DAC chip to crunch, or at least crunch well; 3) the proprietary filters and modulators in HQP are more sophisticated and complicated than the ones in any DAC chip. They just do a better job, and you need the computing power of a PC to compute them; 4) having the computing stuff done outside the DAC means the DAC itself has an easier time, and creates less internal electrical noise that can negatively effect the SQ.

You get HQP and play with the settings till you find those you like. It isn't hard.

miguelito's picture

Through VNC you can access everything just as in any computer, so you can set things up whichever way you want. It is through remote VNC that SG provides support, which is great for someone looking for a turnkey solution.

Boogieman's picture

Thank you for the replies. I apologize in advance for the naivete of my questions, but I am a simple plug and play guy who just like to enjoy music instead of futzing around:

- As a practical matter, if HQ Player works so well, should DAC manufacturers in the future release 2 versions of their DACs, with one as is, and one optimized for HQPlayer?
- What is the "secret sauce" of HQ Player? What are similar products, and why is HQ Player better?
- Why does this server lack an SP/DIFF connection? In my case, I already own a very expensive SP/DIFF cable that took me a long time to find and it rocks my world (too embarrassed to admit in public how much I paid for it). Furthermore, as I mentioned I am a simple plug and play guy, yet my buddies who are into this digital stuff always say "USB sucks!" and recommend to stay away from it. Furthermore, I find DSD dull...Why now go out and get another USB cable?
- And maybe one would need a new DAC also that is optimized for this server...

Nevertheless, seems like an OUTSTANDING product...

solarophile's picture

- HQ Player is good because it has more accurate filters and options compared to the builtin DAC filters. No need for 2 versions of a DAC. So long as the DAC can handle high bitrate, like 24/384 and DSD128 and above.
- "Secret sauce" is the algorithms used in the player and the almost countless options you have to select which you use.
- SPDIF is an old interface that is synchronous and more jittery. USB is better in all the tests I have run into from the objective folks and I agree. USB does not suck.

Don't worry, not eveyone likes DSD.

Michael Lavorgna's picture
...and no need to apologize.

There is no need to optimize a DAC for HQPlayer. HQPlayer sends a DAC an 'optimized' signal. This optimization, if you will, is tailored by the user to his/her own taste.

Please go to the HQPlayer website and read about it. You can also find *tons* of information online.

Re. S/PDIF, please read Sound Galleries comment (EuroDriver) here

People who believe "USB sucks!" are doing something wrong.

No, you do not need to get a DAC 'optimized' for this server -- this server works with any DAC. Again, see Sound Galleries response.

Ultrarunner's picture

Michael, perhaps I missed it, but did you compare the SGM to Roon playing to the microRendu in NAA mode? In other words were you using HQPlayer in both setups?

Michael Lavorgna's picture
The sonicTransporter, which I use as Roon Core/Server, cannot run HQPlayer.
CarterB's picture

Small Green Comouter has an optimized HQPlayer box for $2k, I am curious how they compare (and also curious why it is so hard to find on their website)

Michael, have you done a formal review of HQPlayer? I'd be curious your general thoughts on usability and performance.

Michael Lavorgna's picture
Since I have not heard (about) the sonicTransporter for HQplayer + Roon Server, I cannot offer an comparisons. Perhaps some time in the future...

I have not done a review of HQPlayer but this is something I plan to do.