My working assumption, however, is that most buyers of the Icon HDP would use both the DAC and the amp sections together. Thus my sonic comments above are based on plenty of listening with both amp and DAC in circuit.
On “Young Blood” from Norah Jones’ The Fall [Blue Note], the electric bass has good string definition, but the weighting of the bass falls on the light side of absolute realism. The vocal sounds I heard were open and clear, yet smooth and realistically resonant.
On The Unthanks’ song “Because He Was a Bonny Lad” from Here’s The Tender Coming [Rough Trade], the opening voices are presented in a natural acoustic whose decay you can hear amazingly well (it isn’t smeared over). The two-part voices on this track sound deliciously delineated, though you might be sensitive to a slight whiteness in the treble.
The opening guitar and following kick drum on Shelby Lynne’s “I Cry Every Day” [Suit Yourself, Capitol] show off the dynamics of the HDP. The acoustic guitar is naturally highlighted against the studio background with excellent delineation. When the kick drum comes in it adds a marvelous rhythmic pulse, but is missing a touch of slam.
Returning to The Fall, the track “Its Gonna Be” reveals a very slightly less dynamic rendition overall when using the HDP’s DAC than with the Esoteric player’s DAC. Bass is also slightly less defined with the HDP, though in some cases treble purity may be higher. Differences in perceived purity between the Icon HDP and Esoteric are in any event very small, since in some cases the Esoteric seems cleaner, while at other moments (as on “Its Gonna Be”) the HDP takes the lead.
The Icon HDP easily drove all the headphones that we tried (as listed in the introduction above). The most difficult, as usual, were the Beyerdynamic DT-990’s, as these could be driven to “Danger!, Danger!” volume levels with relative ease. There are amps that seem to have a bit more output than the HDP, but it isn’t obvious that this does anything for the user.
As always, we should remind our gentle readers of the standard caveat that value is a function of your budget and your needs. That said, it is hard to imagine a logic that would find the Icon HDP anything but an excellent value, assuming you need both a headphone amp and DAC. Generally, you could easily pay the $449 asking price for either the DAC (with 24/192 capability, no less) or for the headphone amp, but here you get both in one well-priced package, and they are individually quite good.
In the end, purchasing decisions will have more to do with the sonic character of the HDP than with what you get for your cash, since there is no question that the Icon HDP delivers lots of functionality for the money. The HDP will suit some listening preferences and some headphones better than others.
The amplifier section of NuForces’s Icon HDP offers low distortion, sonic clarity and good drive capability, and it is backed by a very good DAC. The Icon HDP suits headphones with strong bass or less than vivid midrange particularly well.
NuForce Icon HDP Headphone Amplifier/DAC/Preamp
Frequency Response: 10Hz -100 kHz, - 0.5 dB
Analog Inputs: RCA or 3.5mm
Digital Inputs: S/PDIF - Coaxial or 3.5mm Optical, 24 bit/192 kHz
USB DAC: USB 1.0 and 1.1 up to 44.1kHz/16-bit, USB 2.0 Full-Speed up to 96kHz/24-bit
Analog Outputs: RCA
RCA Output Impedance: 100 Ohm
Headphone Output Impedance (6.3mm full-size headphone output jack): 10 Ohm
Headphone power output: