Dan D'Agostino Momentum M400 MxV monoblock power amplifier Associated Equipment

Sidebar 2: Associated Equipment

Digital sources: dCS Vivaldi Apex DAC, Vivaldi Upsampler Plus, and Vivaldi Master Clock; Innuos Statement NextGen Music Server; Uptone Audio EtherRegen, AfterDark Giesemann Emperor Double Crown Master Clock, and Nordost QNet Ethernet Switch, all powered by Nordost QSource linear power supplies (2); Synology 5-bay 1019+ NAS, Small Green Computer Sonore Deluxe opticalModule, Linksys mesh router and Arris modem, all powered by HDPlex 300 linear power supply; Apple 2017 iPad Pro and 2017 MacBook Pro laptop with 2.8GHz Intel i7, SSD, 16GB RAM.
Preamplifier: Dan D'Agostino Momentum HD.
Power amplifiers: Dan D'Agostino Progression M550, Karan POWERa monoblocks.
Loudspeakers: Wilson Audio Specialties Alexia V.
Cables: Digital: Nordost Odin 1, Odin 2, and Valhalla 2 (USB and Ethernet), Frey 2 (USB adapter); AudioQuest WEL Signature, Wireworld Platinum Starlight Cat8 (Ethernet), OM1 62.5/125 multimode duplex (fiberoptic). Interconnect: Nordost Odin 2, AudioQuest Dragon. Speaker: Nordost Odin 2, AudioQuest Dragon. AC: Nordost Odin 2, Valhalla 2; AudioQuest Dragon and Firebird. Umbilical cords: Ghent Audio Canare for HDPlex 300 LPS and NAS; QSource Premium DC cables with Lemo terminations for QSources.
Accessories: Grand Prix Monza eight-shelf double rack and amp stands, 1.5" Formula platform; Symposium Ultra Platform; Nordost 20 amp QB8, QKore 1 and 6; Titanium and Bronze Sort Kones, Sort Lifts; Stromtank S 2500 Quantum MK II power generator; AudioQuest Niagara 7000 and Niagara 5000 power conditioners, NRG Edison outlets, JitterBugs; ADD-Powr Sorcer X4; Environmental Potentials EP2050EE surge protector/filter; Wilson Audio Pedestals; A/V RoomService Polyflex Diffusers; Resolution Acoustics room treatment; Stillpoints Clouds (8); HRS DPX-14545 Damping Plates; Stein Music Blue Suns; Bybee Room Neutralizers; Absolare Stabilians; Marigo Aida CD mat.
Room: 20' L × 16' W × 9'4" H.—Jason Victor Serinus

Dan D'Agostino Master Audio Systems
5855 E Surrey Dr.
Cave Creek
AZ 85331
(480) 575-3069

jimtavegia's picture

I do like his comment about distortion as with so many liking tube amps this makes sense to me. It is also true as you review and then measure so not to be swayed by what JA1 finds out.

As hard as this is for me to say, this pair of amps at their price compared to some of the prices we read about at the recent shows that are 6 figures, this pair of amps may be a bargain for those who can afford them, as well as the fact that they look superb.

David Harper's picture

I promised myself some months ago that I wasn't going to troll this forum anymore. And, so far, I have kept this promise. 80K. 2 mono amps.
Bargain. God give me strength.

Anton's picture

Well, entry level integrated amps are now 22,000 dollars, so keeping our betters fed seems to be working!

noamgeller's picture

My youtube channel started to recommend me
Interviews of homeless people in LA and the surroundings...many of those poor souls are truly fascinating, illuminating even. Now stumbling on this article and the sentence contains "bargain" must means that something is really rotten with us humans. Shame, shame on us, truly ):

RobertSlavin's picture

I just want someone from the Dan D'Agostino company to explain why this is a reasonable price for this pair of amplifiers.

The reviewer should have asked the company this question. But Serinus never asks this basic question of the manufacturers of the many expensive products he reviews. Price is a very important consideration in a review of a product but not one he seems to pay attention to.

TJ's picture

Congrats JVS on the successful outcome of your AC rewiring project (!) and thank you for this fine review. As a long time Krell user, I’m always intrigued to see what Mr. D’A is doing next.

As compelling as the SQ of his latest amp must be, I can’t help but wonder how it would compare to an SPL s1200, or even the smaller s800 which I am listening to as I write this. These amps have an interesting gain stage with 120V rails, a minimal number of output transistors in a cascode configuration and exemplary build quality. Their surprising clarity, stage depth and deep bass are even more interesting. Definitely worth a listen if you have the opportunity.

MZKM's picture

The Rotel Michi M8 is more my aesthetic, is <1/5th the price, has less distortion and a ton more wattage.

I would like to see the people for who this aesthetic is for.

Anton's picture

This amp would look perfect in Admiral Harriman Nelson's quarters on the USOS Seaview!

Maybe even better in Captain Nemo's rec room on the Nautilus!

It's got more of a seapunk look than a steampunk, but that is just a matter of nuance!

georgehifi's picture

Doubt any Class-D could ever match this kind of BJT powerhouse.

Real amplification for those nasty hard to drive of speakers which only sound stunning when driven correctly.

Cheers George

Jason Victor Serinus's picture

As I prepare to start coverage of T.H.E. Show on Friday, I see multiple comments about the term "bargain" and scratch my head. This is not a term I used in my review. Nor is it a word that I would ever apply to monoblocks that cost almost $80,000/pair.

Products cost what they cost. Those who can pay the price enjoy them; those who cannot have alternatives. The Rotel Michi, mentioned above, is a product I also reviewed in stereo form and praised highly.

jason victor serinus

Ortofan's picture

... decade, DDMAS did offer an entry-level "bargain" stereo amplifier in their version of a plain, black box. The sole front panel adornment was a copper plate bearing the engraved signature of its creator. The Classic Stereo amp then sold for a mere $13,500.

That model is no longer in the current product line-up. The entry-level stereo amp is now the Progression S350, for about $27K. Apparently, DDMAS customers are unwilling to forgo the fancy chassis and the ostentatious power meter.

haroon's picture

John; kindly explain the distortion spikes that coincided with the zero-crossing points in the signal's waveform. Where is that, "more class-A goodness" in this new version?

John Atkinson's picture
haroon wrote:
John; kindly explain the distortion spikes that coincided with the zero-crossing points in the signal's waveform. Where is that, "more class-A goodness" in this new version?

Yes, the second-harmonic waveform is overlaid with spikes at the sinewave's zero-crossing points, but the level of the distortion is still very low, at 0.029%.

As the Momentum 400 MvX runs very hot, I suspect that the designer adjusted the output stage's bias current to ensure that the amplifier didn't overheat.

John Atkinson
Technical Editor, Stereophile

David Harper's picture

why is this forum so dead? Is it because most people have outgrown interest in audio gear? I'm asking a legitimate question. Or maybe young people just don't understand why anyone would care more about gear than about music? This hobby (if that's what it is) is dying. We are an anachronism. Not that I care. Change is inevitable. But it is an interesting question isn't it.

stereostereo's picture

All questions could be somewhat interesting based on their validity. Maybe you care about the gear more than the music but that has not been my experience based on my audio retail store. At my most recent Woofers and Whiskey event I had over 30 people here between the ages of 15-23. And more than 50 between the ages of 25-40. And the main driver has been overwhelmingly ones love of music. I stress to the industry folk who help me with these events to "just play music and have fun." No discussion of crossovers or woofer materials. And people have really responded and the discussions usually center around The Beatles, Frank Sinatra, Frank Ocean or Frank Zappa. That ain't about a hobby it's about a passion for music. And honestly I have not seen that much change in our industry. Sure the gear has gotten better, prettier, Hi res audio, etc but the one element that has remained constant is our passion for music. And that will never change.

Glotz's picture


Anton's picture

700,000 plus visits per month, dead or not dead?


On the other hand, Audio Science review gets 1.3 million plus.


Absolute Sound, 390,000


I guess the question is how 'lively' qualifies as not 'dead?'

Glotz's picture

And yet no response to your circulation figures as an "I'm wrong, sorry."

If he went to an audio show he would see that the places are jammed with tons of people with a variety of backgrounds and ages... and spending levels.

Time to come out of the house, dude. There's a whole world out there! And it's FUN!