Network Audio Players/Servers

If the C 700 looks like a scaled-down M10 [HFN Jun '19] then, in key respects, it is – the latter's ES9028 DAC replaced by an ES9010 here just as the Ncore amp module is exchanged for a more cost-effective UcD102 in the C 700. The M10 and C 700 are rated at 100W and 80W/8ohm, respectively, and while the former has the edge in continuous power at 100W/8ohm and 200W/4ohm vs. 95W/130W from the C 700, the little newcomer has a more impressive and load tolerant dynamic performance at 121W, 226W, 302W and 196W into 8, 4, 2 and 1ohm loads [see Graph 1, below]. As we saw in the M10, all digital and analogue inputs are managed digitally and finally passed to the UcD amps after D/A conversion at 48kHz/24-bit, so the response of the power amp is limited to –0.3dB/20kHz (and –2.5dB/21kHz) regardless of the incoming sample rate.

The preamp outs, however, extended to within ±0.2dB at 20kHz, 45kHz and 90kHz with 48kHz, 96kHz and 192kHz digital inputs, respectively. The digital filter is a standard linear phase type while jitter is very low at less than 12psec with 48kHz/24-bit files and typically ~10psec at 96kHz/192kHz. The A-wtd S/N is wider, relatively, via the preamp than the power amp outputs (the former 106.1dB, but the latter at 79.1dB re. 0dBW is a little below average) though distortion is tightly managed in the UcD amps at 0.003-0.01%/1W and 0.009-0.025%/10W (all 20Hz-20kHz). Via USB in/pre out, THD is as low as 0.0004% through bass and mid over the top 30dB of its dynamic range [black trace, Graph 2] but is uniformly higher at 20kHz – a minimum of 0.0025% – over the top 20-30dB of its dynamic range [blue trace]. Linearity is true to ±0.1dB over a 100dB range. PM