Rega AOS MC

The Rega AOS MC is a dedicated moving coil phono stage designed to extract exceptional detail, definition and realism from vinyl playback. Its circuit design is heavily influenced by Rega’s reference Aura MC, bringing high-end analogue engineering to a compact half-width component. With adjustable loading and two gain settings, the AOS MC can be matched to a wide variety of low-output moving coil cartridges.

The AOS MC uses an entirely analogue two-stage amplifier design with no digital control circuitry in the signal path. Its aluminium case helps shield the sensitive internal electronics from unwanted RFI, while a self-adjusting servo system compensates for variations in operating and ambient temperature.

The first amplification stage uses carefully matched, ultra-low-noise FET transistors in a symmetrical complementary Class A configuration. This arrangement avoids bias current flowing through the cartridge coil and eliminates the need for coupling components between the cartridge and input stage. The second stage employs a symmetrical Class A differential amplifier and handles the active low-frequency section of the RIAA equalisation.

Resistive input loading can be selected between 70Ω, 100Ω, 150Ω and 400Ω, while capacitive loading is adjustable between 1000pF and 4300pF. Two gain settings provide 69.3dB at 1kHz in the high-gain setting and 63.5dB at 1kHz in the low-gain setting, allowing the AOS MC to accommodate cartridges with differing output levels. It is factory preset for compatibility with Rega moving coil cartridges.

Frequency response is rated at 17.5Hz (-3dB) to 100kHz (-0.2dB), with RIAA accuracy better than ±0.2dB from 65Hz to 70kHz and total harmonic distortion of 0.03%. Power consumption is 20W during operation and 0.4W in standby. An automatic standby function places the unit into sleep mode following a period without a signal and can be disabled using rear-panel DIP switches.

The Rega AOS MC measures 220 x 80 x 330mm (W x H x D) and weighs 2.9kg. Its custom aluminium half-width enclosure complements Rega’s wider electronics range while providing effective shielding for its low-noise analogue circuitry.