Overview
The M 40 HV combines our experience in the various areas of High-End audio technology: audiophile valve construction for the input stages, High Voltage technology for the transistor stages, intelligent thermal processor control for the output stages together with our usual uncompromising case design and construction.
Valve Technology
To achieve all this we have equipped our finest power amplifier with a circuit design which is unique in the world, combining classic analogue techniques, valve technology, High Voltage amplifier design and intelligent parameter control. The entire input amplification section is based on carefully selected High-End valves of the 6SN7 type, operating in Class-A mode. This results in a very harmonious sonic image, and instils the musical and tonal advantages of valve technology in the sound character of the M 40 HV.
Amplifier Concept
The input stage is designed as a symmetrical differential amplifier exploiting an all-valve cascode circuit. The subsequent voltage amplifier stage is a High Voltage (HV) J-FET amplifier circuit with triode performance characteristics, which also operates in pure Class-A mode. The result is excellent bandwidth and an agile performance which defines the sound qualities of the amplifier as a whole. At the input side the current amplifier stages are based on MOSFET driver transistors whose performance curve harmonizes superbly with the HV voltage amplifier stage. At the output side the current amplifiers are equipped with no fewer than twenty extremely high-performance ring emitter bi-polar transistors. These components satisfy the most extreme demands in terms of current supply capacity and bandwidth.