But there were limits. Superb dynamics didn't mean infinite volume. While the feisty DM-9a was capable of startling dynamics on short-term peaks, it could be pushed to resonance with musical content in the 250Hz range at outputs of 80dB/1m. So count the M1-ST as an intimate speaker in the mold of a latter-day Quad, not a frat-house party animal. While it could dish deliciously detailed and dynamic with the sensuous fare mentioned earlier or Dorian's scintillating "Woods, Rocks, and Mountains" from The English Lute Song or Linn's Garden of Early Delights, it was less comfortable with material requiring more enthusiastic sustained SPL like Daft Punk's Random Access Memories or the DeadMau5 single "Seeya". There it could deliver all the detail and complexity but not the visceral impact required to make one get up and dance. But no speaker is all things and SPL are not the single arbiter of audio quality. Otherwise Stax and Quad wouldn't still be regarded with such respect. And that's a fitting end to our discussion on the sonic merits and limitations of the Ultrumax. It's time to examine relative value and competition.

The M1-ST may have absolute musical virtues but for its $2'850 ask isn't yet a complete speaker. To achieve full speaker status, the price goes up and depending on your choice of configuration and quality, considerably so. My ad-hoc SVS add-on raised the stakes by $1'000 and should be considered the minimum starting option. Mark & Daniel's equivalent IIa subwoofer starts the turnkey game at $1'350. Going full stereo adds $4'000/pr for their top docking modules decked out with their best woofers. Top dollar will guarantee best match and a full-range floorstander that also raises the high-pass filter to 350Hz to coax some additional dynamic muscle from the AMT. That should make for a formidable speaker system but also with a total cost approaching $7'000. With such a wide latitude of price ranges, it pits the M1-ST against some very stiff competitors, some of them top names in the audio world.

The M1-ST checked most boxes that describe panel speaker behavior so the obvious comparisons are there. The Magnepan LRS is an industry darling and real $650/pr bargain benchmark. It is more cohesive than the satellite/sub combo and standalone more full-range than the M1-ST. The LRS achieves similar SPL with better dispersion. The Ultrumax however is in another league with its purity, speed and low-level resolution. Sticking with Magnepan, their 1.7i and 3.7i at incrementally higher prices still come in cheaper than M+D's top modular combo and add greater output, more dynamic range and full line-source radiation. They also narrow the Ultrumax's lead in resolution and purity if not quite match it. The Magnepans however have the strength of full-bandwidth cohesiveness inherent in a pure panel design while the Mark & Daniel system adopts the blended flavor of a good hybrid. That logically pits the top Ultrumax against the Martin Logan ESL hybrid. For a tag about $1'850 less than the top Ultrumax, the Electromotion ESL X has the low coloration of an ESL, a similar crossover point and the virtues of taller line-source dispersion. Its bass response however will be outmatched by the bass-augmented Ultrumax. For $1'000 more than the upper Ultrumax combo, the Classic ESL 9 ups the ante of the X, adds internal amplification and better woofers to match the Ultrumax bass response as well as even better dispersion. The Ultrumax can match or beat both these ESL on purity, low-level detail and adds that unique ability of dynamic thrust but falters on overall output level, dynamics and dispersion. The fact that we're talking tit for tat in such distinguished company gives an indication of the performance achieved by the Mark & Daniel Ultrumax M1-ST. Each competitor has different strengths and weaknesses so choice comes down to individual listening preferences, not drastic levels of technical or sonic superiority. These are all thoroughbreds.

If you've stuck with me this far, you've heard everything I heard and lived my experience with the Mark & Daniel Ultrumax M1-ST. Advertising hype pretty much matched reality. It is indeed an AMT the likes of which hasn't been heard before. It sets benchmarks and introduces a new vocabulary that cement it as state of the art for the breed. The M1-ST will not fulfill the needs of the ear-shattering dance crowd but delivers purity and energy to satiate the heart of any Quad devotee. Choose your bass solution and enjoy your own journey. Treat this diva with respect and she won't just sing but soar.

Quality of packing:  Shipping container was double thick cardboard, internal packaging honeycomb-reinforced thick cardboard with sheet polystyrene compartments.
Reusability of packing: Yes.
Condition of components received: Functionally perfect but not up to Mark & Daniel's normal quality standards.
Delivery: Arrived by courier.
Website comments: Mark & Daniel have a comprehensive website covering speaker products, raw components and accessories as well as company philosophy and background.
Human interactions: Approachable and responsive.
Warranty: 2 years against defects in materials and workmanship (see manufacturer's website for details).
Final comments & suggestions: The M1-ST introduces the finest AMT Mark & Daniel have ever built and is simply the most advanced driver of its kind on the planet. Assuming that QC on final production runs polishes appearance to match performance, this speaker will become quite the petite powerhouse.

Mark & Daniel respond: "Thank you Glen and 6moons for the very detailed appraisal of our new Ultrumax-M1-ST speakers. As Glen mentioned, the DM-9 AMT drivers exposed certain limitations at certain frequencies under higher sound level pressures. Indeed, during our R&D stages the biggest challenge was the SPL capability of the super-wideband DM-8 and DM-9 AMT drivers in the lower band around 200Hz. Previous M&D AMT drivers worked well across their 800Hz-20KHz bandwidth and with admirable SPL aptitude. With the new Ultrumax-M1-ST we tried to challenge ourselves to extend the operating bandwidth downwards by a factor of 4 which represents an ambitious jump from 800Hz to 200Hz. On paper this multiplies the physical displacement magnitude of the pleated diaphragm by a factor of 16 to generate the same sound pressure level. In real engineering practice, we're limited by how much we can actually increase the spacing of our pleated folds. We believe that the distortion witnessed by Glen came from the ripple effects of undesirable vibrations between the folded membranes when certain music hit 200Hz at high volume.

"We are now working on a modification to the DM-8/DM-9 drivers. One effective measure for instance is the reduction of the number of pleated folds on the DM-9 driver down from the original 28 to 24 folds. By reducing the number of folds to increase the spacing between them, we will accommodate larger displacement. This will reach the low frequencies as intended so with minimal distortion also at higher outputs. At the same time we are carefully re-examining all other parameters to optimize the overall sonic performwance. We are confident that these modifications will arrive at an even more coherent sonic conclusion very soon."