As if all this were not enough, the SA-KI Ruby has a dedicated headphone amplifier with discrete circuitry and a laser-engraved signature on the top with a ruby motif that is presumably glass, but nevertheless catches the light rather nicely.
When Ken Ishiwata demonstrated this product at its launch, he used his laptop as a source, running JRiver 23 as the playback software. The result was very good, but I couldn’t help thinking that even the best set up laptop is a poor substitute for a decent audio server. The results I got at home backed this up and revealed the DAC side of this machine to be extremely good indeed. I used the Innuos Zenith SE and connected to the Marantz with Vertere HB USB cable – controlling playback with Roon revealed that the SA-KI Ruby is down with this most reliable of control apps.
The overall character is of effortless musicality, as with the SA-10 that it so closely resembles, this DAC is magically quiet, which means that you can hear deep down into each recording. It’s the quietest sounds that make the difference with digital audio; in the past you got the impression of silent backgrounds, but in fact what happened was that the smallest sounds were hidden in the noise floor created by distortions peculiar to the medium. This Marantz breaks through that barrier by taking noise down that much further. It makes for thrilling listening especially with tracks that tend to sound a bit messy like Van Morrison’s ‘The Way Young Lovers Do’ [Astral Weeks, Warner Bros]. This track is always lively thanks to the almost freeform nature of the arrangement and while a good DAC can get it to flow in coherent form this Marantz manages to make it sound almost polished with excellent stage width to boot. Some might prefer a grittier, ‘warts and all’ presentation, but this smoothness doesn’t get in the way of the detail; it just makes less pristine recordings sound more relaxed and easy to enjoy.
It’s also not lacking in dynamics as there’s plenty of drive and energy on tap where it’s required and it’s very hard to press stop; the album’s title track sounded pretty damn beautiful as a result. Roon chose Dylan’s ‘Subterranean Homesick Blues’ [Bringing it all Back Home, Columbia] as a follow up, I guess the vibe is similar, and this was raucous glory personified with as much vitality as you could want. I also like the way that it delivers enormous differences in image scale and depth between recordings; it’s something that should change to some degree with every change of disc, but not all converters give you the full effect.
The SA-KI Ruby seems to be very good at picking out the ‘voice’ in the music, whether that be a piano, a saxophone, or an actual voice, it highlights this rather than the rhythm or dynamics, and it does that regardless of format. I guess that given it turns everything into one bit prior to conversion it’s not surprising that DSD sounds very similar to PCM. I contrasted a recording of Mozart’s ‘Violin concerto in D major’ [Marianne Thorsen, TrondheimSolistene] in both formats from the 2L label. They were both deep and wide and replete with detail so that the only real difference was a stronger sense of melody with the PCM, and for some reason this version seemed more compelling than the DSD. But both sounded very fine indeed.