The “Intelligent Output Drive” topology implemented at the heart of our amplifiers offers the advantages of operating in class AB, while maintaining the absence of crossover distortions characteristic of a class A. It features an intermediate driving stage fitted with 6 transistors together with a local feedback loop.
INTELLIGENT DRIVERS
This output stage driver topology, integrated into the B.audio amplifiers, is the result of numerous simulations and acoustic tests in order to eliminate the crossover distortions which are generated by Class AB output stages.
Principle of operation
The IOD consists of a driver stage fitted with 6 transistors operating in class A, and is inserted between the voltage gain stages and the output transistors.
He plays the following 2 roles:
– Deliver a drive current to the output transistors under any circumstances, reacting instantly to changes in their impedance, especially in the crossover area.
– Buffering the feedback currents generated by the loudspeakers, to enable the previous voltage gain stage to operate optimally regardless of the amplifier load.
Local feedback loop
Featuring a local feedback loop, the output stage of our amplifiers always exhibits a high impedance to the previous stages. This enables the amplifier to operate perfectly linearly, in all circumstances.
Efficient power usage
This topology then makes it possible to obtain the absence of crossover distortion usually reserved to Class A output stages, while keeping power consumption under control. In combination with an extremely low output impedance thanks to the oversized output stage, it ensures optimal operation with any load.