In the first weeks with the SGM 2015, we experimented extensively with HQPlayer's settings. From its filters and noise shapers, we finally arrived at what to our ears felt best. This is very personal and also depends on your ancillary equipment. We went through our complete arsenal of speakers, amps plus the LampizatOr DAC which meant the Æquo Audio Ensis, Volya Audio Bouquet and Mark & Daniel Maximus Ruby MkII loudspeakers. For the T+A DAC, we eventually arrived at a buffer setting of 50ms, a 32-bit word length and ply-sinc-shrt-mp oversampling filter. For the noise shaper we most fancied ASDM7. Though the difference between DSD256 and DSD512 was very subtle, we did chose the latter and thus had a bit rate of 22'579'200 with a recommended maximum volume of -3dB. When using the T+A DAC in PCM mode, we ended up with the same filter setting but now with NS5 dithering and an output sample rate limit of 384'000. Part of HQPlayer's oddity is that when you open its settings menu, the music stops. When resuming play after a setting change, the filter must be built up again. Also, we found that placing a Shakti Stone on the T+A DAC added soundstage depth.

Having a good interface with your music collection is crucial when streaming audio. We loved the integration with Roon which led to unified access for all kinds of off/online storage including Internet radio which regardless of source quality is all converted up to DSD512. With these capabilities mostly manifesting as very clear-sounding wide aural vistas and very attractive reproduction of dynamics, our choice of music became more critical by the day to focus on well-recorded well-produced content. That could be played at very low volumes without any masked detail. A bad recording was sometimes bearable at higher volumes which is probably also why the recording is 'off' – it was recorded too loud in the studio to begin with. On our list of favorite recordings played multiple times were Pierre Bensusan's Encore, John Scofield's Country for Old Men, Bernard L'Hoir's She's, the Jaume Compte Nafas Ensemble's Tariq and Voda, Ibrahim Maalouf 's Live Tracks - 2006/2016, Leonard Cohen's Live in Dublin, Agnes Nobel's Aventine, Enya's Watermark, Erik Voerman's Nocturnal Ghost Songs, Robert Wolf's Together and the Nicolas Parent Trio's Tori. Playing these recordings from the SGM into the T+A DAC into a Music First passive preamp and nCore 1200-based power amps whilst only swapping speakers offered us clear insight into the strengths of this source. In all combinations, the color balance leading to tonality, smoothness and liquidity added up to unequalled transparency. Each loudspeaker drank from the musical source and reflected the flavour in its own way. Our Pnoe horns set a soundstage that went on deep and wide behind the speakers. The Avantgarde Duo Omega put us front row centre with the musicians while the Mark & Daniel Ruby MkII monitors created a remarkably wide soundstage that covered the full width of our room. The stunningly painted Volya Bouquet with its ceramic and diamond drivers was lucid and detailed, the Æquo Ensis revealed lots of stage height information and the Sounddeco Alpha F3 set the stage for a cozy club experience.

Re: PCM vs. DSD, there runs a sort of religious controversy. As with all religions, it's about beliefs, not facts. We think that what is/sounds better depends entirely on the DAC. During the review period we had two very special converters on hand. Both the LampizatOr Atlantic and T+A DAC8 combine two internally separate converters sharing only a minimum of circuitry while offering discrete PCM and DSD processing. The LampizatOr handles PCM by means of a discrete R2R ladder while the T+A does PCM via a quad array of 32-bit BurrBrown converters in a double symmetrical circuit. This compensates for nonlinearities and reduces background noise by 6dB. Once data converts to analog, it flows to discrete symmetrical output stages without any operational amplifiers. In theory, PCM is easier to handle than DSD. PCM uses lower frequencies to be less prone to ultrasonic noise and interferences. However, PCM conversion uses more parts when not running a 1-chip-does-all method to reintroduce noise potential. Chipless DSD conversion uses very few parts and is basically a simple low-pass filter. That filter must be top notch. Here a superior filter combined with a lower DSD sample rate can produce better results than a lesser filter with 'superior' (higher) sample rates. The moment noise enters, fine sound is gone. Comparing LampizatOr and T+A converters was like comparing two apples and two oranges; the fully chipless Atlantic to the semi-chipless DAC8. Since the Polish DAC couldn't handle DSD512, our DSD comparison ran both with HQPlayer set to DSD256. The DAC8 adds a switch for wide or clean to set filter bandwidth to 120kHz or 60kHz. We used wide. The Atlantic DAC was fixed.

With PCM, we thought the LampizatOr with its discrete R2R ladder combined with a direct-heated pentode output sounded the most pleasant and relaxed. Processing DSD turned tables. DSD256 via the DAC8 gave more detail and spatial information without getting clinical or cold. The LampizatOr provided a smaller musical vista; a subtle difference but noticeable. Stepping up to DSD512 over just the DAC8 added still a little more location information about instruments across the virtual stage. Thus our conclusion for this comparison was that chipless PCM via discrete resistor ladder was superior to on-chip processing; and that for native DSD processed with just a low-pass filter, said filter's quality was most crucial. Also switching between DACs meant uninstalling one ASIO driver and installing another followed by a renewed USB handshake so instant A/B were impossible.

In conclusion, we loved the SGM 2015. It is a complete, easy-to-operate system, stable, handles all kind of digital sources, comes with extended service support and delivers a tonally rich unstressed signal to the rest of the audio chain. Of course such quality comes at a price. The SGM 2015 is not the cheapest but, at the very cusp of 2017, clearly the best we've come across yet. This, we expect, should remain unchallenged for many years. That's because all of its software is upgradeable and, should the need arise, even the hardware can be run on other operating systems. In short, investing into this music server is a safe bet. We actually think that with the arrival of the SGM 2015, high fidelity has just become fine fidelity and not only for the small principality of Monaco.

Sound Galleries Monaco website