Предусилители — MasterSound Phl 5

The MastersounD Phl 5 is a Class A valve preamplifier with a fully valve-based moving magnet phono stage. It was the first preamplifier MastersounD made, and the company has revised it several times since, building each unit by hand at its workshop in the Vicenza area.

Key specs that matter

Two ECC802 double triodes form the line stage, and the MM phono stage adds two ECC803 and one more ECC802. In its current edition the rear panel carries four line-level sources (three unbalanced, one balanced) plus the phono socket, and the outputs are a main pair on RCA, a main pair on XLR and a record out on RCA. Output impedance is 450 ohms, RIAA equalisation holds within 0.5 dB, and frequency response runs from 1 Hz to 100 kHz within 0 dB. The Phl 5 draws 24 W, measures 44 x 39 x 14 cm and weighs 10 kg, and a remote control for volume is supplied.

Engineering and use context

The latest edition is recognisable by its thick plate of satin-finished aluminium. It moved to a new circuit board layout and gained an analogue signal filtering system first used in the Spettro preamplifier, along with the XLR connections. Earlier versions had four RCA line inputs, no balanced connections, and two main outputs that allowed bi-amplification, built on gold-track circuitry. A V2 revision of that older model brought a small circuit change aimed at lower noise. That generation used three ECC82 and two ECC83 valves, weighed 9 kg and was specified for about ten minutes of warm-up before its circuits stabilised. The phono section accepts moving magnet cartridges only, so owners of MC cartridges must add a step-up transformer or use a separate MC phono unit. The factory advises switching off before changing any cables and never touching the valves while the unit is hot. Valves are tested and matched by MastersounD before the unit ships, and the preamplifier carries a five-year warranty that excludes the valves.

Pairing

The balanced output makes the Phl 5 a direct match for MastersounD power amplifiers fitted with XLR sockets, among them the 845 Monoblock and the Booster, and its 450 ohm output impedance is low enough for normal lengths of interconnect. The RCA output serves power amplifiers without XLR sockets, while the fixed-level record out suits a recorder or a separate headphone amplifier.

Alternatives

The MastersounD Spettro is the more elaborate preamplifier derived from the Phl 5, using a Dual Drive System with four ECC802 in the line stage and 250 ohm output impedance.