Yes and no. How's that for definitive? Here's why. Traditionally, recorded bass is mixed to mono from 100Hz on down. Those waxing eloquent on the virtues of stereo bass on their vinyl pressings may have missed that lecture. Now a 190Hz crossover point leaves 90 cycles without full stereo treatment. But since our eyes and ears love the illusion of continuity, if there's sufficient relevant data playing simultaneously above 190Hz, our brains connect the dots and steer the events to stereo. Since this trick is a fragile sleight of hand, careful setup aids in the deception. A subwoofer located centrally between the speakers will be preferable to a lifestyle scenario of hidden sub unless you like your mono panned à la Dolby Pro Logic. During the review, the arrangement generally worked flawlessly especially with material of wide frequency response to hide the seams. Therefore concept and practical application earned my yes in the majority of circumstances but with a proviso. Even with the setup at optimum, I found a few instances where the illusion was exposed, for example with jazz recordings like Fourplay where the bass guitar occasionally fell into that phantom 100-190Hz zone and became an SVS solo. It was a rare occurrence but for audio scrutinizers who find that a fault once heard will always be heard, it'll be firm grounds for a no and they should automatically look to the stereo bass alternative.

And that's about all I can say on 3rd party bass integration. I heard no glaring shifts in character, no obvious differences in responsiveness. Ideal marriage? While the single sub was functional, stereo woofers remain the gold standard. Count my match largely positive as long as the subwoofer was held to the maxim "the component that contributes best is the one noticed least". That truism to accept supporting role should apply to any bass solution for our Ultrumax satellite, stereo or mono. It's because the petite M1-ST is a superstar. Cue the spotlights. But our M1-ST also plays the devilish diva and demands due diligence before she'll reveal her ample charms. It all comes down to our star's beaming radiance.

The wave launch of the DM-9a driver acts as a 4.5" monopole line source with horizontal dispersion of some ±30°, say ±15° for critical listening but essentially no off-axis dispersion in the vertical plane. This extremely focused radiation demands careful attention to positioning, especially height. The positive consequences of such restricted dispersion are obvious. Since the M1-ST has no back wave or port and produces no floor and minimal side-wall reflections, it will deliver pristine first-arrival information and a gloriously coherent sonic event within the designated seating area. In a classic equilateral triangle, it will absolutely dazzle in the nearfield and rank top choice for critical listening. Outside that area of optimal focus, performance becomes considerably less stunning however so those who assemble their musical environment for a more social event will want speaker placement closer to the front wall to maximize on-axis radiation and minimize off-axis driver nulls. Mark & Daniel actually offer on- or in-wall placement option for their lower U-1a Ultrumax model so such a circumstance is anticipated. Ultimately you should regard the M1-ST as a critical listening tool so experiment and decide what works best for you. That pretty much forewarns of our diva's demanding nature. Now it's time to reveal her abundant charms.

If you've encountered an air-motion transformer before, you'll already know its basic character. Fast, detailed and dynamic are the descriptors. Now picture that character extending down in frequency not stopping at 1000 or 800 cycles, not even Mark & Daniel's former limit of 600Hz but a new record of 190Hz. Say hello to the core frequencies of male and female vocalists as well as acoustic instruments. Hear them freshly delivered with the combined attributes of wideband electrostatic and ribbon transducers. Add a twist of dynamic thrust. You've just met the Ultrumax M1-ST. Hello baby!