Network Audio Players/Servers

Our sample of the M3 was not only fitted with the optional network card but also the very new headphone preamp. At the time of writing, no technical specification for this amplifier had been posted aside from the fact that it is (necessarily) a fully balanced solution configured to drive both 4-pin XLR and single-ended 6.35mm outputs. In practice, Bricasti's headphone output registers 8.8V at '+1' volume and 7.85V at '0', clipping at the '+2' setting. Adjusted for a 600ohm load this represents an output of 100mW while the amplifier retains sufficient current to support 845mW/25ohm at >1% THD, the latter impedance representative of the 'average' load measured across our comprehensive headphone reviews. Distortion is very low indeed and typically <0.0005% through bass and midrange and <0.002%/20kHz at 10mW/25ohm.

The frequency response of the preamp is determined by that of the DAC stage [see Lab Report, p61] but its impressively low 315-650mohm source impedance means the M3 will manage the varying load of low impedance 'phones without exaggerating any existing peaks and dips in their acoustic response(s). Channel separation is ~95dB across the 20Hz-20kHz range. Noise, too, is very low and the ultimate A-wtd S/N ratio very wide at 116dB – the M3 will drive the most sensitive of headphones without obvious background hum. PM