The reference Aura MC stage is the culmination of decades of electronic design development. We have created the ultimate, fully adjustable, three-stage, all symmetrical pre-amplifier designed purely to extract the very best performance from your moving coil cartridge and vinyl playback system.
Built into a completely re-designed custom case, the Aura is dedicated to moving coil cartridges and stays clear of any compromises. We have avoided including any superfluous functions as they obstruct the signal path and degrade the sound quality. The Aura phono pre-amp incorporates remarkable and innovative design ideas. If you are a vinyl connoisseur, then the Aura MC is an absolute must for demonstration.
The first stage is a symmetrical, complementary class A amplifier, using parallel connected Linear Systems ultra-low noise FET (Field Effect Transistor) transistors configured as a symmetrical compound pair input stage. 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.
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.
The third stage inverts the signal to provide the balanced output along with the output of the second stage; the third stage uses the same circuit topology as used in the second stage. The power supply is a symmetrical, discrete tracking power supply using fast diodes and a low noise voltage reference. Each stage has its own localised power supply and LED referenced current generators. To maximise headroom, the Aura has a power supply voltage, which is 60% higher than normally found in such a pre-amplifier. Very high quality, polypropylene capacitors have been used in the signal path. 1% tolerance polypropylene capacitors are used in the RIAA EQ stages and audio grade capacitors are used in the rest of the circuit. Gain, Mute and Mono switching is implemented using high-quality relays.