Rega AOS MC Moving Coil Phono Stage

Rega AOS MC Moving Coil Phono Stage

The AOS is a dedicated no compromise fully adjustable moving coil preamplifier using a circuit design based heavily on Rega’s award-winning Aura reference MC phono stage. Housed in a custom made Rega half width case, the AOS will deliver exceptional definition and greater realism to all of your recordings, bringing your favourite vinyl to life.

Designed to work with a wide range of moving coil cartridges it has plenty of gain for low output MC’s and excellent load adjustability making it the perfect partner for whichever Moving Coil you are using.

The AOS is a two stage “all analogue amplifier” with no digital control circuitry. The fully aluminium case screens the internal circuit from any stray RFI signals. Rega’s designers have avoided including any unnecessary components or circuits that may degrade the signal path. The AOS incorporates many innovative design ideas including a self-adjusting servo control which compensates for any variations in ambient or operating temperature.

The AOS utilises parallel connected, low noise FETs (Field Effect Transistors) configured as a compound pair. The MC input has the provision for selecting resistive input loading of 70 Ω to 400 Ω and capacitive loading of 1000 pF to 4300 pF. The input sensitivity can be changed by 6 dB via the back panel. An automatic standby feature has also been added which puts the unit to sleep after a period of no signal. This can be deactivated via dip switches located on the rear panel.

Precision Class A FET Input Stage For Pure Phono Signal Integrity

The first stage is a symmetrical, complementary class A amplifier, using Linear Systems ultra-low noise Field Effect Transistors. The use of FET transistors ensures there is no bias current flowing in the cartridge coil so as not to upset the delicate magnetic geometry of the cartridge. The input circuit configuration also alleviates the use of any coupling components between the cartridge output and the input stage FET transistors, which would degrade the sound. The complementary ultra-low noise FET transistors are carefully graded and matched for optimum performance. This stage drives the passive high-frequency part of the RIAA equalisation stage.

Class A Differential RIAA Stage

The second stage is a symmetrical, class A, differential amplifier with a common base driver stage; this is also used as the active amplifier in the low-frequency part of the RIAA equalisation stage.

Is the Rega AOS MC an Aura on the cheap?

This is an extremely even handed and revealing phono stage and one that does thrilling things with the output of a decent moving coil cartridge. I particularly like the way that it reveals so much without resorting to a forward leaning balance, this can sound fast and exciting but can also be too much for many recordings. The Aos MC has perfect timing and delivers the musical goods in a compelling fashion, if you really want to know what’s cut into the groove wall, take your favourite vinyl down to your local Rega dealer at the earliest opportunity. The Ear Review

Why Choose The Rega AOS MC?

The Rega AOS MC Phono Stage is a seriously accomplished moving-coil preamp that channels much of the design DNA from the flagship Rega Aura MC Phono Stage, but in a more compact half-width chassis that feels purpose-built for vinyl die-hards. Fully analogue and proudly free of digital control circuitry, it’s all about preserving the purity of the signal, with a carefully honed two-stage Class A design built around ultra-low-noise FETs that keep the cartridge’s delicate magnetic geometry intact while pulling astonishing levels of detail from the groove. Parallel-connected low-noise transistors, wide-ranging loading options, switchable gain, and clever servo control that compensates for temperature changes all work quietly in the background, letting the music breathe. The result is a phono stage that sounds effortlessly revealing and beautifully balanced — fast, articulate and packed with nuance — bringing a level of realism and musical flow that makes favourite records feel newly alive without ever tipping into showy hi-fi theatrics.