Audio-GD Master 9 MK3

With the Master 9 MK3, Audio-GD presents the latest version of its headphone preamplifier/amplifier. This model builds on the success of its predecessor, still being a dual mono Class A headphone amplifier. With this new iteration, Audio-GD has mainly worked on the miniaturisation of its amplifier, going from a 16kg model to a 7kg model, without making any concessions to the quality of sound reproduction.

The Master 9 MK3 incorporates a gain adjustment function, making it easy to adapt to any type of headphone, even the most difficult to drive.

- The "L" (Low) mode has a gain of 16dB, making it suitable for powering headphones with a sensitivity of even more than 100dB, or for use as a preamplifier.

- The 'H' (High) mode has a gain of 25dB, enabling headphones with a sensitivity of between 80 and 100dB to be powered.

The Master 9 MK3 has a dual mono architecture, so the right and left channels each benefit from an R-core transformer and 4 dedicated Class A power supply modules. The Class A modules used have a very high input impedance to prevent impurities from passing through the block and affecting the preamplifier, and a low output impedance, high speed and high linearity. The result is a very clean power supply with virtually no impact on the final sound reproduction.

The output stage uses a diamond structure for its circuit. This particular structure uses 4 transistors in a configuration reminiscent of a diamond crystal if represented schematically, it has the dual advantage of being fast and accepting high loads. Four 150W transistors are used per channel, operating in pure Class A. As a reminder, Class A amplification has the particularity of having its active components always in conduction. As a result, they amplify the input signal in its entirety, greatly limiting the total rate of harmonic distortion at the output. And so, thanks to its diamond structure and Class A operation, the Master 9 MK3 has signal processing that's both fast and distortion-free, for a result of rare quality.

The 100% discrete design of this amplifier (no OPA) is supported by a volume control that differs from conventional methods. Traditionally, volume control takes place in the input stage of the amplifier via a potentiometer to reduce the signal. The main problem with this method is that the quality of the potentiometer has a direct impact on the quality of the sound, which can easily lead to a loss of detail, channel imbalance or distortion that will later be amplified. 

Finally, the Master 9 MK3 is equipped with ACSS output. This is a proprietary technology of the brand called ACSS for Audio-GD Current System Signal. Thanks to the company's expertise and know-how, this technology offers a less coloured, more detailed sound with unrivalled neutrality. When the ACSS output is used, the XLR and RCA outputs switch to mute mode.

The Master 9 MK3's remote control not only controls the preamplifier/headphone amplifier, but also an external Audio-GD DAC, if you wish to pair one with the Master MK3.