Design Philosophy

Introducing the new AGD “GaNTube88MkIII” – a culmination of two years’ relentless development and an unwavering commitment to acoustic perfection. This latest iteration marks a significant leap forward in sound quality, a result of tireless refinement and long hours of attentive listening.

Central to this advancement are two fundamental components of the GaNTube amplifier module: the PWM stage, (specifically the Voltage-Time converter block), and the output filter – now entirely re-engineered with more advanced materials and new design techniques.

The “GaNTube88MkIII” retains its 800KHz operating frequency, but with dramatic improvements. 

The PWM and LC stages have been meticulously enhanced, resulting in reduced distortion, lowered noise, expanded bandwidth, and lightning-fast response times.

Rated at 250W 4Ω, the “GaNTube88MkIII” delivers its maximum RMS output power when paired with AGD Vivace MKII mono-blocks.  With the AUDION MKII mono-blocks, the power is limited by the internal power supply, at 200W.

With the new MKIII, we have extended the frequency response of the power stage, now flat up to 60KHz, and by a combination of layout improvement and the re-engineering of the output filter, we managed to also significantly increase the slew rates performances.

This evolution enhances the sonic landscape, presenting an immersive musical journey literally out of this world.

Experience audio in its purest form by upgrading the AUDION and the VIVACE to the GanTube88KT MKIII

AGD: Where innovation meets excellence and exceeds all expectations

100+ Years of “AUDION” Evolution

The AUDION Tube 1906 (Triode from 1918)

1906 Lee de Forest’s tube was named Audion, then it became Triode because it was the name used by Lee de Forest’s competitors. 

In time “Audion” faded away,  displaced by “Triode”, and forgotten, and the rest is history.

AGD GaNTube MKIII

• Gallium Nitride Power MOSFET
• Up to 250W 4ohm, >800KHz PWM.
• New advanced PWM stage
• New output filter
• Extended bandwidth

The AGD GaNTube88KT MKIII Amplifiers

• The new AGD GaNTube 88KT Mk III is compatible with any version of the AGD Audion and AGD Vivace mono-blocks.
• The GaNTube88KT is NOT COMPATIBLE with the Gran Vivace

Rise time and Fall time

Rise time: ~15ns

Fall time: ~11ns