Интегральные усилители — Musical Fidelity M6SI500

The M6si500 is a dual mono stereo integrated amplifier from Musical Fidelity, part of the M6 series that also holds the M6x DAC, the M6scd CD player, a streaming integrated and separate pre and power amplifiers. It is a purely line level design with no internal phono stage, so a turntable needs an outboard phono preamplifier plugged into a spare RCA input.

Key specs that matter

Musical Fidelity rates the output at 500 W per channel into 8 ohm, which it also expresses as 27 dBW. Total harmonic distortion plus noise is typically below 0.01% across 20 Hz to 20 kHz, while noise sits more than 100 dB below the reference level, A-weighted. The frequency response is given as +0 and -0.1 dB from 10 Hz to 20 kHz, a much tighter tolerance than the usual 3 dB window. The rear panel offers five sources in total, with four unbalanced RCA sockets and one XLR balanced pair. The chassis measures 440 mm wide, 160 mm high and 460 mm deep, and the unit weighs 30 kg net, with 35 kg quoted packed.

Engineering and use context

Musical Fidelity builds it as a true dual mono design, with a separate heat sink and a separate transformer assigned to the power section of each channel. The preamplifier section is fed from a dedicated winding, keeping its supply apart from the heavy current demands of the output stages. Every channel uses 12 large bipolar output transistors, and the maker quotes a capability of 200 amps peak to peak. Circuit boards are joined directly rather than through long wiring runs, which Musical Fidelity says keeps signal path impedance low. One of the RCA inputs doubles as a home theatre bypass, letting an AV processor drive the power stage at a fixed gain, allowing the M6si500 to power the two front channels of a multichannel setup while still acting as a normal stereo integrated. Outputs comprise one RCA preamplifier output and one fixed level RCA output, the first suited to feeding an active subwoofer or second power amplifier and the second to a recording device or headphone amplifier.

Pairing

The XLR input is a good match for a balanced source like a streamer or DAC placed a few metres away. The heavy build and the deep chassis call for a sturdy rack shelf with space behind for cables, and the high rating leaves ample margin for low sensitivity floorstanders in rooms of about 20 m2 and larger.

Alternatives

The Musical Fidelity M6si is the lower powered integrated amplifier within the same M6 series.