Audio-GD Master-9P: Balanced headphone and combo amplifier

The Audio-GD Master-9P is a superb fully balanced headphone amplifier and combo amplifier, featuring a newly developed ACSS design that delivers sound as precise and transparent with XLR as with...

Audio-GD Master-9P
Audio-GD Master-9P

The Audio-GD Master-9P is a superb fully balanced headphone amplifier and combo amplifier, featuring a newly developed ACSS design that delivers sound as precise and transparent with XLR as with ACSS. It also features an optimized power supply, providing an extremely clean and stable electrical signal for all audio circuits.

Audio-GD Master-9P

The Master-9P’s amplifier stage features a unique current amplification stage (ACSS) for the shortest possible signal path and particularly neutral and accurate sound reproduction. This ACSS amplifier has very low distortion and is soldered directly to the main PCB. The amplification and preamplifier stages here operate in class A. The output transistors operate with a high quiescent current. The special design of this cascade avoids switching distortions.

Audio-GD Master-9P

ACSS used in the Master-9P architecture is an open-loop technology using discrete amplifiers. The combination of ACSS and open-loop circuitry achieves excellent dynamics, detail and sonic neutrality while maintaining low distortion and high linearity. The ACSS stage uses four groups of high-quality Class A power supplies. This parallel connection provides high input impedance to prevent power supply pulses from interfering with the gain stages.

Audio-GD Master-9P

The Master-9P output stages use Linear Fidelity technology. They have no feedback, but maintain very low distortion and provide excellent linear performance.

Audio-GD Master-9P

The use of powerful components combined with a reliable power supply provides high output current, allowing the Master-9P to accompany demanding speaker systems. The Master-9P uses four channels of open-loop output stages consisting of eight ON Semiconductor transistors, each rated at 230W/15A. The capacity of the entire set reaches 100,000 uF, two transformers with a power of 600 W are used.

Audio-GD Master-9P

The Master-9P volume control system operates on the input stage of an analog amplifier through a potentiometer that allows the signal to be attenuated using relays and resistors. Here the volume control uses variable passive I/V conversion at the ACSS amplifier output and does not degrade the signal quality.

The Master-9P features complete separation of the left and right channels of the amplifier, power supply and transformer. It also uses a heavy aluminum alloy chassis to prevent transformer eddy currents from affecting the circuit board.

Characteristics of Audio-GD Master-9P:

  • Product Type: Amplifier
  • Amplifier Type: Class A
  • Inputs: 2x XLR/2x RCA/1x ACSS
  • Outputs: Speaker Terminals/1x Stereo XLR Headphone Out/1x XLR 4-pin Headphone Out/1x Jack 6.35mm Headphone Out
  • SNR: > 110 dB
  • Gain: High Gain: 34dB/Low Gain: 20dB
  • Amplifier output power: 2x100W @ 4 ohms/2x70W @ 8 ohms
  • Headphone Output Power: 2x35W@15ohm/2x20W@25ohm/2x14W@40ohm/2x6W@100ohm/2x2W@300ohm/2x1W@600ohm
  • Input Sensitivity: XLR : 0.55Vrms/ACSS : 2mArms
  • Input Impedance: RCA: 47k ohms/XLR: 94k ohms/ACSS: 10 ohms
  • THD+N: 0.05% @ 20W, 8 Ohm, 1kHz / 0.002% @ 20W, 8 Ohm, 20kHz, 2Vrms, XLR input / 0.055% @ 60W, 8 Ohm, 1kHz / 0.005% @ 60W, 8 Ohm, 20kHz , 2Vrms, XLR input
  • Supply voltage: 220-240V AC 50/60Hz
  • Consumption: 50WW
  • Dimensions: 430 x 430 x 93 mm
  • Weight: Approx 16kg
  • Black color

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