The MAESTRO is a direct descendant of the critically acclaimed spa1 headphones amplifier. Serving the demands of discerning headphone aficionados, the unit was designed for an outstanding listening experience with any type of dynamic and planar-magnetic headphones. Furthermore, the MAESTRO is the heart of any HIGH END stereo system by providing a state of the art line – level preamp function.
Incoming audio signals (balanced or unbalanced) pass through the 4 times independently working amplifier stages; additional difference amplifiers or inverters you often see in lesser designs are simply not needed. Compared to all other circuit designs, the fully-balanced configuration provides a much better behavior in the time domain. The balanced signal of the left and right channel is output at an identical speed, providing superior pulse fidelity.
|Fully balanced signal path|
|Usual design showing pulse distortion due to skewing||MAESTRO 4X design showing perfect summing of phase + and phase –|
4-ganged volume attenuator
The crucial part in creating a fully balanced control amplifier is a 4-ganged volume attenuator with perfect tracking between channels and phases. MAESTRO SE features the all new MUSES 72320 volume attenuator (one per channel !) controlling the output level with extraordinary accuracy and sonic neutrality. The MUSES 72320 chip is an array of tight tolerance resistors providing volume settings between 0dB and -100dB in 0.5dB increments. Mediocre opamps, often found in integrated volume control chips are not used, leaving the precious music signals intact.
The output stage of the MAESTRO SE operates most of the time in pure class A. In case of higher impedance headphones like HD800 (300 Ohms), the MAESTRO SE will never slide in to class AB operation. Likewise, MAESTRO SE will always work in class A in preamp mode because the load currents are significantly lower. MAESTRO SE is capable of driving long, high capacitive interconnects to power amplifiers without any losses.