Thrax Heros, Class A Hybrid - Tube/FET Amplifier

Heros

Class A Hybrid - Tube/FET Amplifier

Heros is a very unusual hybrid transformer loaded amplifier marrying old concepts with the latest technology. The numerous benefits from using an output transformer are usually ignored mostly due to cost reasons.
Yet when done correctly the result speaks for itself.

Features

Tube amplifier architecture with the simplest signal path

Transformer coupled input and output

JFET/MOSFET cascode output devices

Silicon Carbide diodes in power supply

Microprocessor control

Selectable gain

Selectable speaker impedance

Audiophile 5687wa tube used

Fully balanced differential operation

Both RCA and XLR inputs

Compact chassis built like a tank

100W Class A power output

Based on a push-pull output stage but modified with our design concepts and experience it features a tube input stage providing the necessary voltage amplification. Followed by transformer loaded cascoded JFET/MOSFET output stage instead of the usual tube handling current gain much better.
Almost double the efficiency of a normal Solid State Class A design, no DC on output and many other benefits are taken advantage of in our implementation.
A fully differential architecture using an input phase splitting transformer and summing back at the push-pull output transformer. This solution completely floats the inside of the amplifier isolating it from any external influences.

The design being fully differential is immune to power supply noise.
The power supply for the output stage uses a new breed of rectifier diodes made from a new material called Silicon Carbide. They have no reverse current and switching losses.
When properly applied the rectifier produces no EMI/RFI in the chassis. The result is an amplifier free of grain and fizziness, giving new meaning to transparency and tone.
We use the well-known 5687WA audiophile tube and the highest grade audio transformers. Operating all devices in class 'A' produces a fair amount of heat, so the whole chassis is a heat sink. It is the most compact 100-watt class A solid state amplifier available.

The chassis is designed to cope with the heat produced by the components and provide a vibration-free structure to house the components. All the electronics are enclosed in separate compartments to avoid interference between components.
Blending this with stylish aesthetics produced a beautiful sculpture - To be known as Heros.

Technical Specifications Inputs 1 unbalanced RCA connector
1 balanced XLR connector Output Power 100W in 4Ω/8Ω Power supply 115 or 230V Power consumption 230W Weight 30 Kg Dimensions 210W x 400D x 230H mm Tube compliment 1x 5687 amplification

Available Finishes