The iconic amp continues to lead.

The original Momentum Mono amplifier was the first product designed and manufactured by the company and the latest version, the Momentum M400 MxV Mono amplifier, elevates this iconic design to its greatest height. The Momentum M400 MxV models incorporate techniques and topologies initially developed and implemented in the Relentless Mono amplifier. This ultimate expression of Momentum circuitry is reflected in the new model's name, MxV. Those with a background in physics will recognize that MxV or mass times velocity is the Momentum equation.

Advances in all areas.

All the main sections of the amplifier - power supply, input, driver and output stages - have been improved in this advancement. A new transformer winding provides more than 50% more output current with the same transformer size. This additional current offers greater leeway during dynamic passages. A reinterpreted input stage combines an entirely new circuit topology with advanced components that power the drive and output stages. The bipolar transistors that feed the front end of the amplifier are crucial to the new circuit. In the Momentum M400 MxV amplifiers, the new devices deliver ten times the current and power of the original devices. These higher-power, higher-bandwidth components extend low- and high-frequency performance with reduced distortion at both frequency ends. In the drive stage there is a new bias stability circuit that provides an almost 50% increase in operating bias. Increased performance in Class A directly correlates with better sound quality. However, the bias level of any amplifier has a limit. With this new circuit topology and our exclusive copper heatsinks, thermal issues are not a practical concern on the Momentum M400 MxV amplifiers. The new bias scheme ensures bias consistency, preventing excessive temperatures even under the highest demand. Additional power transistors in the output stage reduce the workload of each device. By minimizing the effort of each individual device, the entire output section works more efficiently. The result is a richer, more dynamic and more intimate presentation, regardless of the musical genre.

The final output stage features new output transistors that were originally used for the Relentless monoblock amplifier. The high output transistors used in the Momentum M400 MxV are among the fastest available. With 26 in the Momentum M400 MxV amplifiers, they run at an impressive 69 MHz, allowing the Momentum M400 MxV to achieve incredible bandwidth. Each transistor is mounted with two stainless steel fasteners - a rarity among packaged transistors - for maximum heat transfer to the copper heat sinks. A network of capacitors/resistors connected to the base of each transistor ensures stability even at high frequencies and with low impedance speakers. What's more, each output transistor is measured and only devices that meet the required performance specifications are included in the production of Momentum M400 MxV amplifiers. Like all D'Agostino models, the Momentum M400 MxV amplifiers feature direct-coupled discrete balanced circuitry, the most precise circuitry platform possible.

Power to spare.

Defying its compact size, the Momentum M400 MxV is one big power amp. The backbone is the new 2,200 VA ultra-quiet linear transformer. A new winding scheme reduces the hysteresis effect by 90%, minimizing power and thermal losses. The combination of these elements provides a 50% improvement in output. This motor drives a nearly 100,000ⲙF capacitor bank resulting in a power output of 400/800/1,600W into 8/4/2Ω speaker loads for the Momentum M400 MxV Momentum M400 MxV amplifiers are capable of driving any speaker to its full potential.

Innovative cooling with Venturi-style heatsinks.

A critical element of any amplifier output stage is the circuitry known as the driver section. In the new Momentum M400 MxV, this stage has a completely complementary design. Individual transistors are used for the positive and negative halves of the musical signal. This nearly doubles the current boost needed to maximize the enhanced output stage that follows. The new output stage takes advantage of this increased boost to increase the open loop gain by the same factor of two. The result is a more authoritative, richer and more expansive sound.

Hand built and individually tested.

Each Momentum M400 MxV monoblock amplifier is hand built and individually tested at the D'Agostino factory in Arizona by our team of technicians and craftsmen.

MxV performance update.

The new Momentum M400 MxV uses the same chassis as previous Momentum amplifiers. All generations of Momentum Mono amplifiers can be upgraded to the performance level of the Momentum M400 MxV. All electrical upgrades are included in the upgrade, while the original metal frame remains. Original Momentum amps receive a new 400-watt metering plate that reflects the power increase included in the upgrade. Momentum M400 units already have this increased power and meter.

Specifications:

Frequency response 1 Hz to 200 kHz, -1 dB 20 Hz to 20 kHz, ±0.1 dB.

Signal to noise ratio 115 dB, unweighted.

Black Silver Finish Custom finishes available upon request.

Input impedance 1 MΩ.

Output impedance 0.11Ω.

Power 400 watts @ 8Ω 800 watts @ 4Ω 1,600 watts @ 2Ω.

Distortion 400 Watts @ 8Ω 0.09% @ 1kHz.

Inputs 1 balanced XLR.

Dimensions 12.5 x 21.5 x 5.25 inches / 31.75 x 54.61 x 13.34 cm.

Weight 95 lbs.

Momentum product class.