AGD DUET GaN-Power Monoblock Amplifier

Design Philosophy

The AGD DUET MONOBLOCK Amplifier, is the newest addition to our state of the art Hi-End Power Amplifiers family. 

The AGD DUET is our first compact MONOBLOCK Amplifier utilizing 100% Gallium Nitride Power MOSFET design for both the output power stage and the power supply. 

The AGD DUET is rated 300W 4 

To achieve these performances in such compact CNC machined cabinet (available fully polished or anodized black), we have designed a new power supply by utilizing the most advanced HV GaN MOSFET available in the market today.

For the AGD DUET we also designed a new mother board with low noise linear supply rails and a superlative analog buffer stage based on AD797 op amps.

To maintain with time the full value of the product , key characteristic of all AGD amps, the GaN-based power stage module utilized in the AGD “DUET” is fully upgradable to next generation GaN-Power modules with new GaN MOSFET devices with advanced performances.

AGD “DUET” GaN-Sound Power Monoblock

The AGD DUET MONOBLOCK uses the same fundamental technology pioneered with the AGD Gran Vivace, AGD TEMPO, AGD AUDION, the first true Hi-End amplifiers based on Gallium Nitride power MOSFET

With the AGD DUET, we have extended the use of the most advance power semiconductor, GaN MOSFET, also to the power supply stage, enabling an increased output power rating and efficiency.

The NEW GaN-Power output stage, based on a new set of discrete high voltage GaN MOSFETs, can operate up to 800kHz and at elevated slew-rates delivering the most sublime sound thanks to its ideal “by the book” oscillations-free switching performances.

The New AGD GaN-Sound Module

Also, with the AGD DUET we have retained the key fundamental feature of upgradable GaNSound power  module.

This is a key feature AGD has maintained with all amplifier designs, from the Audion to the Gran Vivace, the Tempo and now the DUET.

At AGD we firmly believe the customers have the rights to maintain the value of their investment, therefore we enable the possibility to upgrade the GaN output stage module at time when a new GaN MOSFET device delivers a performance and technological  improvement.

The GaN technology in power semiconductor is only 10 years old, versus 60years of silicon technology evolution.

New improved GaN MOSFETs will therefore deliver augmented sonic performances by means an upgraded module in a form of a new GaNTube or, like in the DUET and TEMPO, with a dedicated daughter board, easy to plug-in.

The New AGD DUET main board

The AGD DUET new main board is a 4 layers PCB designed with the utmost attention to minimize noise with optimal control of connections routing.

With extra large copper traces (2oz), the new board presents a perfect ultra-low resistive path and stray-inductance.

The AGD DUET main board is designed to accommodate a large bulk capacitor stack (up to 30,000µF), a key vehicle to support the most dynamic and current demand with difficult loads.

The AGD “GaNSound” Module is easily removable for future upgrades and has an additional copper heat-spreader to maintain the most stable temperature during operation.

The New AGD DUET GaN-Based Power Supply

By adopting a new advanced HV GaN power MOSFETs, replacing the standard silicon Cool-MOS technology of the previous generation design, the new power supply has achieved incremental lower noise and higher efficiency than the previous generation design.

The new PS design has also doubled the size of the front-end capacitors and improved the RF filter section. The overall size of the capacitor bank allows a maximum peak current of up to 50A for the output GaN power stage.

All the incremental improvements deployed in this new advanced design have contributed very significantly to the overall musicality of the AGD DUET.

Measurement Snapshots

Front Side view

The New AGD DUET Cabinet

All the elements that comprise the AGD DUET cabinet are 100% CNC-machined and intended to deliver the best solidity and compactness for audiophiles that are looking to get the superior sound with the most advanced technology on the market today and to “down-size” the footprint and weight of the amps at the same time.

The feet are of conical shape and dedicated set of metal discs are included.

The AGD DUET is available in Black Anodized and silver mirror-polished 

Back Side view

The New AGD DUET Cabinet

The AGD DUET back panel configuration offers easy access to both the single ended and balanced inputs connectors. 

The inputs (completely independent) are selectable via toggle switch.

Two sets of super rugged WBT copper binding posts.

The connections for remote trigger input (12V) complete the back panel configuration.


Nominal Output, 20Hz÷20KHz, 4Ω 300W
THD+N 10W/1KHz<0.005%
Maximum Output Power at 0.1% THD+N, 1KHz, 8Ω150W
Audio Bandwidth ±0.5dB20Hz-20KHz
Bandwidth ±3dB5Hz-80KHz
Input Impedance40kOhm (600Ohm upon request)
GaN Power Module PWM Frequency~800kHz
Dimensions10×5.6×4.0in (254x142x100mm)
Weight8.25lbs (3.75kg)
Input Voltage110-240V (Auto-Switch)

AGD DUET: MRSP  – $11,500 (pair)