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The NSMT Model 20M

(formerly MasterSource Audio 20M by NSM Audio)

NSMT 20M on stands
"masterful imaging"

Images better than Revel Performa M20

Images better than Mirage MRM-1

Images better than the Merlin TSM-SE

Images at least as good as the JMlab Mini Utopia

"...its imaging performance among the best I’ve heard."

(Doug Schnider,

Price per pair: 4,995


 "The 20Ms are noteworthy for their effortless sense of élan and how completely they disappear while making beautiful music... a lot of class, a truthful portal to the spiritual, sensual, emotional, exuberant and universal language that music is...So much so, I purchased the 20Ms and look forward to using them as my new reference." Stereotimes

"Small Footprint, Big Sound."

Russell Lichter Stereo Times

"I sat mesmerized by the precision with which the instrument was rendered."

"The 20M has a precise character that can show startling resolution. Its presentation is lively in the upper frequencies, smooth and a wee-bit laid-back in the midrange, and tight and controlled in the bass."

"Imaging is stellar."

"The best speakers I’ve heard in my room in terms of imaging have been the Waveform Mach MC and the ultra-expensive JMlab Mini Utopia. In this regard, the 20M at least equals these fine speakers."

Doug Schneider

"I purchased a complete 20M Armada system (with two 15 EXP subwoofers) over a year ago which I use daily for audio mastering. This system has simply allowed me to get closer to creating a perfectly balanced master than I ever thought possible."

Kurt Lundvall, Lundvall Mastering


The NSMT Model 20M is a time coherent, point source, first order, two-way acoustic suspension loudspeaker system that is the result of years of research, innovation, and independent thinking, that have yielded many evolutionary refinements. As a result the 20M has exceptional ability to accurately reproduce music and to retrieve the ambiance of the musical performance.

As proof of the "rightness" of the design, few loudspeaker image as well as the 20M.

Several features contribute to the performance of the 20M. The 20M's combination of time coherent, point source, first order, two-way, acoustic suspension designs coupled with innovative cabinet and crossover designs and accurate voicing, make the Model 20M incredibly true to the source.

As a result of its time coherent, point source, coincident driver array, the woofer and tweeter have identical acoustic centers and identical directivites at the crossover frequency. This produces a stable axiosymmetrical radiation pattern with smooth power response.This is further enhanced by a high quality minimalist first order crossover network.

The cabinet of the 20M is finished in real walnut wood veneer. It is elaborately braced and the rear panel is sloped two degrees to eliminate box resonances and colorations. Furthermore, the vertical edges of the cabinet are accentuated with exotic Peruvian walnut hardwood inserts that are rounded to prevent sonic refractions and to enhance the appearance of the 20M.


Special Features:

Design: time coherent, point source, first order, two-way acoustic suspension
Drivers: concentric 7.5 in cast frame TPX woofer, 1 inch soft dome tweeter
Crossover components: Perfect lay copper inductor, film foil capacitor
Connectors: Bi-wire/Bi-amp, insulated five-way gold plated binding posts for cables up to 7 AWG
Cabinet: Walnut veneered 3/4 inch braced anti-resonant MDF with exotic Peruvian hardwood walnut inserts. The back of the cabinet is slanted 2 degrees, from the bottom to top of the back panel to eliminate standing waves in the cabinet.
Finish: Non-toxic, eco-friendly, paint
Wiring: multi-strand copper to woofer and tweeter
Warranty: 5-year limited

NSMT 20M Supra Boxcon terminals










Technical Data
Dimensions: 14 X 9 X 10 (H X W X D)
Frequency Response: 38 Hz-20 kHz
+/-3 dB: 
54 Hz-20 kHz
Sensitivity: 87 dB 1 watt/m
Drivers (each loudspeaker): (1) concentric 7.5 inch coaxial die-cast magnesium basket with TPX cone and fabric dome high frequency unit. 
Rated Impedance: 8 ohms
Minimum Impedance: 6.5 Ohms
Recommended Power: 30-200 watts
Finishes: Natural walnut veneer on MDF with black grills.
Weight: 50 pounds per pair


Excerpts from Reviews

"Small Footprint, Big Sound."

"The [NSMT Mastering Series] 20M loudspeakers are nicely designed, solidly built, and eminently musical sounding performers. They throw a very nice soundstage with good speed and detail and are capable of good bass performance."

"...the song that always does it for me is the classic, Cant Help Lovin Dat Man. Pianist Gene Harris performance is simply marvelous and I always want to stand and applaud every time his solo concludes.... The 20Ms ability to pull the listener into the performance is very important to this song."

"... very high-quality craftsmanship and tight tolerances in the construction."

"The tweeter actually showed incredible range, not getting hard or bright as the music became louder or more dynamic."

"The 20Ms ability to pull the listener into the performance is very important..."

"...this is a highly resolving , intimate-sounding speaker that will appeal to people who value high detail and clarity."

Stereo Times

"The 20M is a very different speaker ... because it uses a two-way coaxial driver from SEAS that looks like a single driver. It has the tweeter mounted inside the woofer, right where the dustcap would normally be. ...The idea in creating a driver like this is so that the speaker acts as a point source -- in other words, as close to a theoretical ideal of radiating sound from a single area.

"I found that both the NSMT Model 10S and Model 5 have remarkable ability to cast a stable soundstage with excellent width and depth. This speaker does this too, but it also manages to focus its image more finely, making its imaging performance among the best I've heard."

"I sat mesmerized by the precision with which the instrument was rendered."

"Compares favorably to the Waveform Mach MC, Mirage MRM-1, Revel Performa M20 and Merlin TSM-SE; 'if you're seeking all-out minimonitor performance, put the unique Mastering Series 20M on your list."

"Fit and finish are excellent..." "Imaging is stellar. "

(Doug Schneider,

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