Definitive Technology StudioMonitor 45 loudspeaker

The Definitive Technology StudioMonitor 45 measures a very room- and back-friendly 11 11/16" (297mm) high by 6¾" (172mm) wide by 11 11/16" (297mm) deep, but these dimensions are attractive for reasons other than simple, efficient transport and placement. I noticed right away that something about the speaker just looked right. Paul DiComo, DefTech's senior vice president of marketing and product development, explained that while the number and size of drivers used in any DefTech design will largely dictate that speaker's height and width, the company nevertheless aims for Fibonacci, or golden-ratio, dimensions. According to DiComo, these efforts help minimize standing-wave and "organ-pipe" resonances inside the speaker's cabinet.

The SM 45 has a 1" aluminum-dome tweeter and a 5.25" mid/woofer, the latter utilizing DefTech's patented Balanced Double Surround System (BDSS), in which the driver's cone is supported at both its inner and outer edges, for longer excursion. The large, unusual-looking knob at the center of the mid/woofer is DefTech's new Linear Response Waveguide. This is designed to create wide dispersion and a smooth frequency response off axis, so that you don't have to be strapped into a narrow "sweet spot" to enjoy good sound—great for listening (and dance) parties.

I was also immediately impressed by the SM 45's solid feel. Knocking on a side panel resulted in a hollow tone that was slight and well controlled—not quite the dull thud you expect from more expensive speakers, but satisfying nonetheless. The SM 45's contoured, high-gloss baffle and tapered side panels are said to minimize diffraction, while internal MDF cross-bracing increases rigidity. (For more on diffraction and how the shape of a speaker's cabinet can influence its frequency response, check out Keith Howard's excellent essay "Cutting Corners.") While unpacking the SM 45s was indeed painless, each speaker weighs a surprisingly hefty 12 lbs—significantly more than my 8.8-lb PSB Alpha B1s, but still 155 lbs lighter than some other speakers around here.

The SM 45's overall fit and finish were outstanding. My review samples seemed to have been roughed up during shipment—the outer box was dented and punctured—but there were no signs of damage to the speakers themselves. I was even more impressed by the fact that I could find no signs of manufacturing defects. Though the SM 45 was designed by a team of DefTech engineers in the US and Canada, it's made in China. Paul DiComo explained that careful steps are taken to ensure reliable, high-quality manufacture: DefTech's handpicked vendors are subjected to a lengthy validation process that includes factory inspections, financial vetting, and reference checks. According to DiComo, the vendors selected are given detailed mechanical drawings for every part of a design, and are required to execute those designs precisely as specified. An extensive quality-assurance program follows every step of production, first abroad and later at home, to ensure that the specifications have been met and the speakers are ready to ship to dealers.

The rear of the SM 45 is dominated by a large, flared bass vent and, in a recess, a single pair of five-way binding posts of a high quality typically found in much more expensive designs. Somewhat unfortunately, the speaker is available in only one finish: a modest wood-grain black matte. But, really, the SM 45's high-gloss black baffle would look garish against any other finish. As it is, the speaker seems to quietly and gracefully disappear into itself. The SM 45's frequency range is listed as 35Hz–30kHz, its nominal impedance as 8 ohms, and its sensitivity as a relatively high 90dB.

Listening to music
It took some time to get a handle on the SM 45's sound. After a couple weeks of casual listening I found its performance still uninspiring, but soon grew to appreciate its gentle, subtle touch. Far from being a "flavor bomb," the SM 45 didn't stand out in any way at all, but simply sat there, making music. Indeed, the SM 45 was very easy to take for granted, easy to ignore. It was, in a sense, the quietest loudspeaker I've ever heard, and "disappeared" in my room as has no other speaker, allowing music to simply bloom throughout my room, to surround and surprise me. It's impossible to say whether the SM 45's sound changed significantly over time or if I grew better accustomed to what it was doing, but everything snapped into focus—literally and figuratively—during direct comparisons with the Polk RTi A3 ($399.95/pair; reviewed last month).

Neneh Cherry and Norwegian free-jazz trio, The Thing, offer a languid version of Ornette Coleman's wonderful "What Reason Could I Give" on their surprising collaboration, The Cherry Thing (CD, Smalltown Supersound STS229). While the DefTechs couldn't match the Polks' weighty bass and more powerful kick-drum blasts, the smaller speakers produced a more tightly rendered overall picture, with sharply focused, three-dimensional images set within an impressively wide soundstage. At 3:40 into the song, Cherry, saxophonist Mats Gustafsson, and drummer Paal Nilssen-Love make way for Ingebrigt Hüker Flaten's lengthy bass solo. Through the Polks, this solo was something of a mess—loose, incoherent, lacking purpose. The DefTechs presented the same minute of music with greater articulation, clarity, and precision, allowing the notes to cohere and the melody to prevail—an absolutely lovely thing.

I'd been most impressed by the Polks' way with rock music, so I returned to "Road Dog," from Dope Body's excellent Natural History (CD, Drag City DC513). Again I was surprised: While the Polks produced the bigger, more aggressive overall sound, they couldn't match the DefTechs' transient articulation, inner detail, and delicate touch. Through the SM 45s, the guitar rakes of the song's opening moments sounded more nuanced and natural: I could more easily hear—in fact, more easily see—a guitar pick hitting individual guitar strings. While the Polks threw those rakes into my room with impressive force, they also made them sound more like simple white noise.

But don't get the wrong idea: The little DefTechs' touch may have been subtle and delicate, but they weren't wusses. They could rock. Compared to my PSB Alpha B1s ($299/pair), the SM 45s offered a similarly well-balanced overall sound, but with more precise imaging, a wider soundstage, and cleaner, deeper bass. Most important to me was the DefTech's ability to reproduce louder, more complex passages of music with no hint of strain or compression. When I turned up the volume during "Road Dog," the PSBs tended to sound slightly stressed out and overmatched—they wheezed a bit. (Not really.)

Special Music
It's funny how even the smallest, seemingly accidental events can alter our ideas and shape the way we view our worlds. One night toward the end of the review period, I casually selected one of the many neglected discs that litter my orange couch: Mouse on Mars' recently released Parastrophics (CD, Monkeytown MTR 022CD), an album that hadn't impressed me at all the first few times I'd heard it. There's nothing special about this music, I'd thought. Well, about three seconds into listening to Parastrophics through the Definitive Technology StudioMonitor 45s, my jaw dropped, my eyes went wide, and I was forced to give myself three slaps in the face: What the hell was wrong with me? The SM 45s' well-controlled lows, impressive dynamics, and stable stereo imaging worked together to reveal intoxicating levels of detail and texture I'd previously missed—another reminder to spend more time enjoying the things closest to me. My apologies to Mouse on Mars. My thanks to Definitive Technology.

Definitive Technology
11433 Cronridge Drive, Suite K
Owings Mills, MD 21117-2294
(410) 363-7148

sangel's picture

In a recent audio fest here in Athens, i had the chance to audition a pair of DefTech SM45 Speakers drove by an Advanced I65 integrate amplifier with excellent, for my taste, results.
Finaly I have ordered the speakers and looking for amplifier alternatives.
Although, i am very pleased with your cerain review regarding the above subject, i would be very gratefull if you can guide me to the following.

Is it worth it to use the next upgraded Nad model that is the C326BEE, shall i gain any benefits regarding audio results;
I am asking because, the above model other than the extra power handling i.e. 50WRMS/CH isteade of 40WRMS/CH has dual SUB outputs - useful for extra soundstage and lower octave - and separate pre/power in/out.

Your reply woulde be very much appreciated

Kind regards

Stelios Angelidis, MSEE, MBA