The NuForce Icon is a very nice, compact unit, but unfortunately the USB connection (the only digital input) no longer works with current operating systems.
However, it can still function very well (in analog mode) as a preamp and headphone amplifier.
Measurements
Signal-to-noise ratio: 115 dB
THD: 0.0013%
Headphone output level: 1.2 W @ 16 ohms, 1.825 W @ 32 ohms, 718 mW @ 100 ohms, 249 mW @ 300 ohms, and 126 mW @ 600 ohms
Headphone output voltage: 8 V at 32 ohms
Line output level: 2 V RMS
Connectivity
1x USB port
1x 3.5 mm stereo mini-jack line input
1x RCA stereo line input
1x 6.35 mm headphone mini-jack output
1x RCA stereo line output
1x RCA coaxial S/PDIF output (75 ohms)
Comes with silicone stand and original power supply.
very good cosmetic and working condition.
No warranty