Jen Chapin’s rendition of Stevie Wonder’s “You Haven’t Done Nothing” from Chapin’s ReVisions [Chesky] is a track that’s powered partly by Wonder’s infectious grooves, hooks, and wickedly funny and politically supercharged lyrics; partly by the sheer chops displayed by Chapin’s band; and partly by the sweet, soulful, sassiness of Chapin’s voice. It’s the sort of track that can sound pretty good through many different types (and grades) of audio equipment, but that really comes alive with equipment that can power, control, subtlety, and nuance, all at the same time. Perhaps for this very reason, I’ve always felt iDevice-driven systems failed to capture the full measure of magic of which I know this track is capable.
The iDo, however, changed all that. I plugged my iPhone and a good set of headphones (the V-MODA Crossfade M-80’s referenced above) and then listened in wonder (pardon the pun) as the iDo unleashed a jaw-droppingly good performance. The acoustic bass sounded wonderfully taut, punchy, and expressive, displaying tons of “snap” on more vigorously plucked notes, while the saxophone sounded appropriately jaunty, with a just-right quantity of delicate reed sounds and breathiness. But the real treat involved Chapin’s voice, where the iDo let me here the crafty way in which she triggered Wonder’s most ironically humorous lyric lines with a profound yet not histrionic touch of “Question Authority”-grade fierceness. Suddenly, thanks to the iDo, my iPhone no longer seemed like a second-class source component, while my V-MODA ‘phones were sounding better than ever.
A recording I’ve long admired for its sumptuous textures, eerily believable soundstaging, and haunting, otherworldly feel is “Timeless” from Larry Coryell, Badi Assad, John Abercrombie’s Three Guitars [Chesky]. What goes on in this track is that first one of the master acoustic guitarists, and then the other two, join forces so that the overlapping and yet perfectly distinct voices of the three acoustic instruments merge and meld in delightful, often unexpected combinations. Midway through the track, Assad (at center stage) switches to a hand-held thumb-harp to add complimentary percussion accents as Coryell (on the left) and Abercrombie (on the right) continue to trade intertwining lines. Because all of the instruments involved play in nearly identical ranges, the track only works to the extent your audio system is capable of resolving subtle textural and transient details that distinguish one instrument (or performer) from the others.
I’ve gotten good but never truly superb results when listening through iPod-driven systems in the past, but again NuForce’s iDo helped turn the situation around in a significant way. For this track, I listened with my ACS Custom T2 in-ear monitors and my trusty iPhone connected to the iDo, and immediately noticed that the iDo unlocked a deeper, subtler performance than the iPhone, alone, could ever have produced. Through iDo, the top-end of the T2 monitors opened up and almost immediately sounded more delicate, refined, and extended, so that I could hear how the harmonic “signatures” of the guitars were each different, as were their attack and decay characteristics in the hands of their respective players. Where the iPhone on its own tended to allow the sound to collapse a bit (so that the difference between the guitars became less distinct), the iDo seemed to free the performance from invisible constraints, allowing it to breathe and flow freely. I also noticed that iDo helped tighten up and refine the already very good lower midrange/upper bass characteristics of the T2 monitors, enabling them to do a terrific job with the lower registers of the guitars and—especially—the lower notes from the thumb harp. The net effect wrought by the iDo was to make the whole performance sound more refined and engaging, again in much the same way that a top-shelf high-end disc player might have improved the sound. What’s very cool, though, is that the iDo brings these benefits without costing an arm and leg.
Up to this point, HRT’s excellent iStreamer DAC ($199) has set the standard for value among Apple-compatible DACs and with good reason; it’s a simple and very good-sounding DAC that’s very reasonably priced.
Now, however, I would say that for just $50 more, the $249 iDo raises the bar in several important ways. Both products are USB Host Mode DACs and offer excellent though by no means identical sound quality (the iStreamer has a somewhat warmer and perhaps more “organic” sound, while the iDo is cleaner, clearer, quieter, and more precisely controlled). However, the iDo ups the ante with arguably superior fit, finish, styling, and ergonomics; with a headphone amplifier that is actually good—not just thrown in as an afterthought; and with a DAC section that offers a coaxial S/PDIF digital output (allowing users to pass Apple-derived digital audio signals to even higher-end DACs, should they wish to do so). Put all these factors together, and the iDo becomes our new Apple DAC value champ.