We’re very enthusiastic about NuForce’s versatile and well-made iDo, largely because it so consistently helps Apple iDevice/headphone-based systems step up to the next level of performance (or even beyond that). We also like the fact that the iDo helps unlock extra layers of performance in what are already very fine headphones, earphones, and in-ear monitors. As one Playback staffer put it, “The iDo makes a much bigger difference than you’d ever think possible,” so that at $249 it represents a legitimate bargain.
One small word of caution: Good though it is, the iDo is probably not the right amp to use with ‘phones known to be ravenously power-hungry. But with most ‘phones, it should afford a substantial step forward in sound quality.
NuForce iDo Apple-compatible DAC/Headphone Amplifier
Resolution/Sample Rate: Supports maxim rates of 16-bit/44.1kHz or 24-bit/48kHz files (from Apple iPod, iPhone, and iPad).
Input: USB (from Apple iPod, iPhone, and iPad). For specific compatibilities, see the “FEATURES” section, above.
Outputs: 1 x coaxial S/PDIF, 1 x stereo analog audio output (variable level, 2 Vrms, via RCA jacks), 1 x variable level stereo headphone output (via 3.5mm mini-jack).
Headphone Outputs: 3.5mm output jack drives headphones up to 300-Ohm (12 mW@300 Ohm)
Frequency Response: Not specified
Dynamic Range: 95 dB
THD + Noise: .01%
Output Power: 1.5W
Weight: 1 lb.
Dimensions (H x W x D): 6” x 1” x 4.5”
Warranty: 1 year, parts and labor