The Pro iDSD’s user controls are clearly laid out and straightforward to use, and there is even a small remote control that can adjust volume settings for both the Pro iDSD and the Pro iCAN headphone amp. The only minor word of caution I might put forward is that many of the Pro iDSD’s user controls feature multifunction combo rotary/push-to-engage control knobs, so that it pays to keep the user manual close at hand until you become familiar with what each knob does. It’s also important to understand that many Pro iDSD control functions are to some degree context sensitive. Once again, the user manual is your new best friend.
During my listening tests I used the Pro iDSD both as a DAC/amp and as a pure DAC operated in conjunction with the iFi Pro iCAN and Pro iESL. I also ran the Pro iDSD with a very wide range of headphones and earphones including the HiFiMAN Susvara and Sundara, Abyss AB-1266 Phi Edition CC, Final D8000, Massdrop by Noble Kaiser 10U, and Campfire Audio Comet and Atlas. At each step along the way the Pro iDSD moved from sonic strength to strength, in the process creating an overwhelmingly positive impression.
First, the Pro iDSD proved quiet enough (at 0dB gain) to use with extremely sensitive earphones, yet powerful enough (at +18dB of gain) to drive even very demanding headphones such as the HiFiMAN Susvara. Further, the Pro iDSD proved ready, willing, and able to play digital audio files of all formats and of widely varying sampling rates and resolution levels. What is more, the unit proved able to transition from bit-perfect playback for PCM or DSD files on up to very high level upscaling in PCM format or very high level remastering in DSD format—all of this in real-time and with nary a hitch or glitch. In short, the Pro iDSD invites listeners to make back and forth listening comparisons between file formats, resolution levels/sampling rates, and also the digital filter options selected.
The Pro iDSD offers more resolution than any other iFi DAC I have heard to date (and more resolution than most competitors at or anywhere near its price). Still, this does not mean the Pro iDSD has joined the ranks of the “detail über alles” brigade; in keeping with longstanding AMR and iFi practice, this is still very much a component that prioritises holistic musical integrity over ‘bleeding edge’ resolution at all costs. As a result, users enjoy traditional AMR/iFi musicality, but with a heaping helping of low-level musical information on the side.
The effects of high level PCM upsampling and DSD remastering are both audible and beneficial. PCM upsampling tends, for example, to make music sound less granular and more whole and complete, with one upshot being that everything from 44.1 PCM files on up to 352.8 DXD files suddenly start to display both sharpened focus and more continuous, three-dimensional contours. A great example would be Kleiberg’s David and Bathsheba opera-oratorio [2L, DXD 352] where the result of upsampling and filtering is a superb recording made even better, complete with a striking quality of ‘reach-out-and-touch-the-performers’ realism.
In turn, DSD remastering—especially at the DSD1024 level—tends to take everything you have ever liked about DSD format material and make it better across the board. With DSD1024 remastering applied, the music sounds effortlessly and naturally detailed, with enhanced (but not exaggerated) qualities of spaciousness and three-dimensionality. To hear these qualities in action try listening to the title track of Return to Forever’s Romantic Warrior [Sony, DSD64], where with DSD1024 remastering Chick Corea’s keyboard sounds at once free-flowing yet incisive, Al DiMeola’s guitar riffs exhibit rich textures and blinding speed, Stanley Clarke’s bass(es) sound incredibly rich and full throated, and Lenny White’s percussion anchors the proceedings with great clarity, punch, and compelling authority. The DSD64 version of the track sounds very fine, but the remastered DSD1024 version helps the music find a whole new gear with richness and energy to match.