This review page is supported in part by the sponsors whose ad banners are displayed below

One might think of the 540's dynamics and ability to differentiate attacks as a small backwards step when compared to the Grand SE, Air and—only with 24-bit files—the Linn Klimax DS. But it was the Soulution’s presentation that simply sounded right when I listened to electronically generated sounds on Homeland or Grabek’s 8 or the acoustic Bill Evans Trio’s Everybody Digs Bill Evans and compared those to vinyl remasters by Kraftwerk, Depeche Mode and such. It’s not that the Solution delivers pure analogue sound. But it is certainly true that the Swiss players shares its vision with some of the best analogue systems.

Super Audio CDs. The Soulution 540 obviously is a SACD player but performs the decoding of such recordings in a more unorthodox way. Most players convert DSD to PCM inside the DAC but Soulution does so sooner inside the main processor unit where the now PCM signal is treated in the same way as LPCM signal from DVD-A usually is. Unfortunately the Swiss don't share information about the post processor signal parameters. We know that the signal is 24 bits. At what sampling frequency—88.2/176.4kHz as the standard frequencies for DSD/PCM conversion—remains a mystery.

This paragraph about SACD performance will be short. I know great SACD players some of which tempted me to buy them for use alongside the Air. The 540 as a SACD player doesn't tempt me at all. Its performance with SACDs was not as good as it could have been, not as ‘analogue’ as the best. It sounded more like CD which is interesting considering how I loved the sound from plain CDs. Yet SACD sounded a bit mechanical and less natural. It didn’t matter whether the source material was analogue master tape, PCM or pure DSD. Perhaps I exaggerate just a bit but the absolutely outstanding performance of the 540 with CDs elevated my expectations to the 7th moon. I really should quit moaning. I always attempt to listen without prejudice but this time I realized very quickly that this wasn’t a sound for me. I won’t claim it was poor. The Soulution is a damn good machine. But playing SACD over it in my opinion is only a bonus and not the main raison d’être of the machine. Interestingly hi-rez files fared quite differently.

Audio files. As always I started my listening session of a D/A converter by watching a movie. This time it was the 2005 TV show Weeds. The first impression was nicely boosted bass, the second that voices became much more distinct which of course improved intelligibility. This sounded just right. I had the same general impression with every genre of music I played later, especially with high-resolution files. The additional bits allowed music to sound more relaxed while also more dynamic. The treble was better differentiated but simultaneously softer and more vibrant. Bass was very strong. When I listened to 24-bit files I understood how the 540 applies a slight emphasis to the lower range. With CDs this was a great thing as it solves the format's main problem of being too lean and dry.

Generally speaking, files played from my Dune Max had very smooth ‘analogue’ textures and a terrific midrange. Differentiation was not clearly better than from CDs or at least it wasn't clearly so from the start although tone colors clearly were superior. The soundstage was similar however. One needs to get used to this sound to fully appreciate it. I think that the performance from CDs was so extraordinary that even the additional information delivered first by SACD and now by high-resolution files did not convince my subconscious to appreciate them as actually being better.


But I also think that audio files remain a bit of a future medium where our industry still must establish some basic performance standards to guarantee top performance. I think a lot remains to be done with the software both on the recording and playback sides. The CD market seems to be much more mature by comparison. That's why 24-bit files didn't impress me right away as CDs did. I took me far longer to appreciate them. I could also easily tell that the signal source mattered where my Dune Max was not good enough for the Soulution.


When I plugged a USB cable into my laptop I received surprising information – Ayon Audio CD-2S. This actually was the last device plugged in which incidentally runs the same Tenor Audio chip as Soulution. That wasn’t the first time this happened. With April Music’s Stello Ai500 player the same information displayed. At the time I used a 5m Acoustic Revive USB-1.0PL cable. Later I wanted to check a shorter cable and used Acoustic Revive’s model USB-1.0 SP with a computer on top of the player. Surprisingly a new driver installed – DigiHub 0/1 Track & S/PDIF. Perhaps the drivers are interchangeable but I have no clue why the other one installed itself.


Generally speaking the USB input sounded very nice but was less dynamic and palpable than S/PDIF accessed by the same files player. It was a very relaxed sound, very clear and resolving, reminding me of other devices that share the same converter DNA. Here the DAC and output stage simply upgraded that sound with more bass and a smoother midrange. Although not as spectacular as S/PDIF, it was still very interesting.