ЦАПы — Musical Fidelity M3X DAC

The M3x DAC is a stand-alone digital-to-analogue converter from Musical Fidelity, the British brand, positioned as its affordable entry into high-end conversion and made in the EU. It carries over many solutions from the more expensive M6x DAC in a full-width chassis, combining a Burr-Brown PCM1795 converter with a dedicated sample-rate converter that upsamples all PCM input, and it offers both single-ended and balanced analogue outputs with fixed or variable level.

Key specs that matter

The DAC chip is the PCM1795, preceded by an SRC4392 sample-rate converter. Inputs are two coaxial and two optical S/PDIF (up to 24-bit/192kHz PCM) and one USB Audio Class 2.0 type B (up to 32-bit/192kHz PCM and DSD256 via DoP or native). Two digital PCM filters and two analogue DSD filters are selectable. Outputs are RCA at 2V RMS and XLR at 4V RMS at 0dBFS, both switchable between fixed and variable, with output impedance below 50 ohms. Frequency response is -0.2dB at 20Hz, +0.1dB at 20kHz and -1.5dB at 70kHz. THD is below 0.005% at 1kHz, signal-to-noise ratio above 107dB (A-weighted), channel separation below -115dB at 10kHz, linearity within 0.2dB down to -100dB and total correlated jitter below 48 picoseconds peak to peak. Power consumption is 15W maximum and below 0.5W in standby. The unit measures 440 x 100 x 363mm and weighs 6.8kg.

Engineering and use context

The SRC4392 re-clocks every incoming PCM signal and converts it to 192kHz before it reaches the DAC chip, so the converter always works at one rate with a clean, locally generated clock. This isolates it from jitter on the incoming S/PDIF or USB signal and lets the analogue reconstruction filter be optimised for a single sample rate. The RCA and XLR outputs have separate output buffers designed for low noise, large voltage swing and high current drive, with wide gain bandwidth and fast slew rate keeping distortion low. The variable output setting lets the unit feed a power stage or powered monitors itself, acting as a digital preamplifier. The power supply uses Musical Fidelity's Super Silent Power Transformer approach - an industrial-grade mains socket with EMI filter and DC blocker feeding a low-saturation toroidal transformer, which minimises mechanical hum and electromagnetic radiation near the digital circuitry. The steel case and milled aluminium front shield the circuits from external fields.

Pairing

The M3x DAC connects to any amplifier through RCA or XLR, or directly to power amplifiers and active speakers using its variable output. Its USB input suits computers and network transports, while the S/PDIF inputs accept CD transports, TVs and streamers.

Alternatives

Musical Fidelity's own M6x DAC is the higher model from which the M3x DAC inherits much of its design.