Dan D'Agostino Momentum S250 MxV Stereo Amplifier

Every major section of the Momentum S250 MxV amplifier—power supply, input, driver, and output stages—has been significantly enhanced. A new transformer winding pattern increases current output by over 50%, providing greater headroom for dynamic passages. The input stage combines a new circuit topology with advanced components, while new bipolar transistors deliver ten times the current and power of the previous generation, improving low and high-frequency performance with reduced distortion.

The driver stage benefits from a new bias stability circuit, boosting operating bias by nearly 50%, which increases Class A operation and improves sound quality. Thermal concerns are minimized thanks to the new circuit and unique copper heat sinks, ensuring consistent bias even under high demand. Additional power transistors in the output stage reduce stress on each device, enhancing efficiency and delivering a richer, more dynamic sound.

The final output stage features new, high-output transistors originally sourced for the Relentless Monoblock. Running at a remarkable 69 MHz, these transistors provide incredible bandwidth, with each mounted using stainless steel fasteners for optimal thermal transfer. A capacitor/resistor network ensures stability at high frequencies and with low-impedance speakers. All transistors are carefully matched to meet performance specifications, ensuring maximum efficiency. As with all D’Agostino models, the Momentum S250 MxV uses discrete, direct-coupled balanced circuitry for unparalleled accuracy.