Musical Fidelity M2scd/M2si CD Player/Amplifier Lab Report

Lab Report

Time was when Musical Fidelity's integrated amps would be specified a little close to the wind, so when I saw '76W/8ohm' and '137W/4ohm' quoted in the M2si's press release (and on many 'hi-fi' websites) I raised an eyebrow. So it was refreshing to see a more measured view taken in the M2si's user manual where the power output is revised down to '60W/8ohm'. In practice the M2si delivers 2x83W/8ohm and 2x115W/4ohm with 118W/201W into 8/4ohm under dynamic conditions, limited to 169W/96W into 2/1ohm by electronic protection [see Graph 1, below]. So this is a beefy enough amplifier for most likely sub-£1k partnering speakers, the A-wtd S/N ratio an 'industry average' 86dB (re. 0dBW) and distortion within 0.002% over the first 25W of its range to 0.004% up to the rated 60W (all 1kHz). Distortion does not increase excessively with frequency – just 0.01% at 10W/20kHz – while the response is flat to within ±0.18dB from 20Hz-20kHz, rolling away to –3.4dB/100kHz.

The matching M2scd player is based around the Burr-Brown PCM1795 DAC and offers a generous 109dB A-wtd S/N from a maximum 2.04V output. The 50ohm source impedance should prove fairly cable-agnostic while distortion is consistently low at ~0.0015-0.002% over the top 20dB of its dynamic range through midrange [black trace, Graph 2] right up to high 20kHz frequencies [blue trace]. MF has chosen a standard linear phase digital filter offering a good 98dB stopband rejection but with some inevitable transient pre-ringing. The frequency response has the merest (inaudible) treble lift of +0.1dB/20kHz while jitter is below the 16-bit test limit of 116psec. All-in-all, both components are very 'clean' examples of the art. PM


Dynamic power output versus distortion into 8ohm (black trace), 4ohm (red), 2ohm (blue) and 1ohm (green) speaker loads. Max. current is 9.8A


THD versus 16-bit CD digital signal level over a 120dB range at 1kHz (black) and 20kHz (blue)

Continuous power (<1% THD, 8/4ohm) 83W / 115W
Dynamic power (<1% THD, 8/4/2/1ohm) 118W / 201W / 169W / 96W
Output impedance (20Hz–20kHz) 0.164–0.172ohm (46-52ohm, CD)
Freq. resp. (20Hz–20kHz/100kHz) +0.0 to –0.2dB/–3.3dB (Amp)
Distortion (20Hz-20kHz, 0dBFs/0dBW) 0.0018–0.0031%/0.0016–0.0097%
A-wtd S/N ratio (re. 0dBFs/0dBW) 108.7dB (CD) / 85.7dB (Amp)
Digital Jitter 117psec
Power consumption (idle/rated o/p) 18W / 266W (7W, CD)
Dimensions (WHD / Total weight) 400x100x400 (375)mm / 15.5kg
Price £799 (each)
Musical Fidelity (Audio Tuning Vertriebs GmbH)
Supplied by: Henley Audio, Oxfordshire, UK
01235 511 166