Compact phono preamplifier for MM cartridges
The Cambridge Audio Alva Solo is a phono stage dedicated to moving magnet (MM) cartridges. Many hi-fi amplifiers have no turntable input: the Alva Solo sits between the turntable and a line input and raises the very low-level cartridge signal to the right level, with a clean, rich and balanced sound.
Gain is 39 dB at 1 kHz, with a nominal output of 300 mV for a 3.35 mV input. Input impedance is 47 kohms with 100 pF capacitance, values suited to MM cartridges.
Low-noise circuit
The switch-mode power supply reduces hum and the surface-mount circuit is laid out to keep noise down and preserve every detail on the record. The RIAA curve is followed within +/- 0.65 dB from 30 Hz to 20 kHz.
Signal-to-noise ratio exceeds 90 dB and total harmonic distortion (THD+N) at 1 kHz is below 0.0025%. Overload margin is greater than 30 dB and channel separation exceeds 85 dB at 10 kHz.
Subsonic filter and balance control
The subsonic filter removes the very low frequencies produced by worn records, which are not part of the music. A rear-panel knob adjusts channel balance and compensates for level differences in the cartridge, for a centred soundstage.
Also on the rear are the MM input and the output on RCA sockets and the ground terminal for the turntable. The front panel carries only the power button.
Power consumption, dimensions and accessories
The Alva Solo switches itself off after 20 minutes of inactivity and uses less than half a watt in standby; maximum consumption is 10 W and the power supply accepts mains voltages worldwide. It measures 176 x 48 x 132 mm (width, height, depth) and weighs 0.68 kg; the finish is grey.
The box contains the preamplifier, the mains lead, the user manual and the safety guide.