Фонокорректоры — Manley STEELHEAD RC

The Steelhead RC is an all-tube phono preamplifier from Manley Laboratories that adds remote control to the Steelhead concept. The circuit is split between a main unit and a separate power supply chassis, and Manley lists it at USD 10,899. Three phono inputs let one owner connect up to three turntables at once, with two moving coil inputs and one moving magnet input, plus a stereo line input that enters after the RIAA stage.

Key specs that matter

Both moving coil inputs load the cartridge through Manley autoformer taps offering 25, 50, 100, 200 and 400 ohms. The resistive moving magnet input offers settings from 100 ohms up to 47,000 ohms. Capacitance is chosen on the front panel from 10 to 1,100 pF in 10 pF steps. Gain has four positions - 50, 55, 60 and 65 dB - and the unit mutes automatically while it is changed. RIAA deviation is quoted as +0.5/-0.3 dB from 20 Hz to 20 kHz and typically within 1 dB from 10 Hz to 100 kHz. THD is 0.0042% at 1 V output and 1 kHz, dynamic range is 101 dB at 1 kHz (1% THD) or 97 dB at 0.1% THD, and maximum output reaches +27 dBm.

Engineering and use context

Valves used are two Sovtek 6922 valves for gain and four JAN NOS GE 7044 or 5687 valves as output buffers, with a JFET first gain stage for low noise. Equalisation is passive. The variable output runs through a motorised Noble volume control and an all-tube White Follower buffer at 75 ohms, while the fixed output bypasses the volume control at 150 ohms. A second output set sits in parallel with the variable outputs to feed an extra amplifier or a subwoofer. The Remora remote works by radio frequency, needs no line of sight and runs on a 9 V battery. Front panel switches cover mute, dim and mono, and there is a sleep and standby mode. Anti-RFI dip switches help in areas with strong radio interference. The design is single-ended throughout, with no balanced inputs or outputs. The main chassis measures 483 x 89 x 394 mm and weighs 6.8 kg, and the power supply measures 343 x 114 x 289 mm and weighs 8.2 kg. Power draw is 100 W, and the mains setting switches between 120 and 240 VAC at 50 to 60 Hz.

Pairing

Because the variable output and remote volume control are built in, the Steelhead RC can drive a power amplifier directly when vinyl and one line source are the only inputs. The fixed output suits a separate preamplifier or an integrated amplifier that handles level itself, and all connections are RCA.

Alternatives

The Manley Chinook is a smaller tube phono stage from the brand, with 45 dB MM and 60 dB MC gain set by internal DIP switches.