Усилители мощности моно — Musical Fidelity M8S-700M

The M8s-700m is a fully balanced monobloc power amplifier from Musical Fidelity, presented as an affordable successor to the limited-edition Titan and based on that design. It is meant to partner present and future M8 series products and comes in a conventionally sized black chassis. Inside, two high-current power amplifier sections are connected in bridged mono.

Key specs that matter

Rated output is 700 W into 8 ohm, or 28 dBW. At the onset of clipping the amplifier swings 78 V RMS from 20 Hz to 20 kHz, or 220 V peak to peak, and peak to peak current reaches 350 A. Damping factor is 210 and there are 10 pairs of output devices. THD plus noise is typically below 0.005% from 20 Hz to 20 kHz, noise sits more than 120 dB below the signal, A-weighted, input impedance is 50 kohm and response is +0 and -1 dB from 10 Hz to 80 kHz. Consumption is 0.25 W in standby, 140 W at idle and 1,500 W maximum at full output. The unit is 440 mm wide, 160 mm high including feet and 460 mm deep including terminals, and weighs 30 kg, or 35.5 kg once boxed.

Engineering and use context

Two paralleled power supplies, generously over-specified, feed the two internal amplifiers, and phase splitting between them is handled by a fully balanced converter circuit with a wide flat frequency response. Each circuit section is isolated in the internal layout to prevent interaction. Because the speaker output is bridged, both red and black terminals carry signal, so neither may be grounded, and the manual asks owners to check before connecting active subwoofers, electrostatic designs or other potentially grounded speakers directly. The unit dissipates a significant amount of power at all times, with ventilation through top and bottom. A selector picks between the single XLR input and the single RCA input, and there is a 3.5 mm trigger input accepting 4.5 to 15 V DC plus a 12 V trigger output, so the amplifier can either be switched by another device or switch others. Mains voltage is 115 or 230 V factory preset, with 100 V as an alternative, and a 10 A IEC lead is supplied.

Pairing

Two pairs of 4 mm banana plug binding posts allow bi-wiring, and XLR and RCA loop outputs feed the incoming signal to another amplifier, for example to bi-amp suitable speakers with further M8s-700m units.

Alternatives

The Musical Fidelity Nu-Vista PAM, a single-channel amplifier from the Nu-Vista series, is rated at more than 600 W into 8 ohm, with four 6S51N nuvistors in its buffer stage and a separate power supply unit.