Monitor Audio Studio 15 loudspeaker:
Page 2 Higher in frequency, the midrange was in general superb (though with one problem area, which I'll come to in a moment). Midband coloration seemed remarkably absent, voices and strings reproducing about as naturally as I can remember. A current favorite test track of mine for violin and cello tonality is the introduction to John Tavener's The Protecting Veil (Virgin Classics VC7 91474-2), which sets a solo cello playing high in the soprano register against some of the most glorious divided string writing I've heard since Vaughan Williams's Tallis Fantasia. On a foundation of double-bass chords, the cellos, violas, and violins build a massively sonorous sunrise. The Monitors allow you to hear each block of instruments sonically intact within the whole, no one emphasized at the expense of others. Violins did occasionally sound slightly exaggerated at the top of their E-string register, but this didn't get in the way of musical communication.

Voices, too, floated free of the speaker positions. I dug out an album I hadn't played for some years, the first Blue Nile LP, A Walk Across the Rooftops (Linn LKH1). Against the sparse accompaniment (including violin parts eerily reminiscent of The Protecting Veil), the lead singer sounded refreshingly free of the midrange muddying that too often homogenizes the tiny inflections of expression. (This is what the concept of "following the tune" is all about.)

Only when it came to recorded piano did the Studio 15 sound a little less than excellent. Though the sound was satisfyingly full, with good midbass weight when driven by the tube amplifiers, the middle registers sounded somewhat congested. Certain notes—the C and D-flat near the top of the treble staff in the Chopin track on the first Stereophile Test CD, for example, which have approximate frequencies of 523 and 554Hz—acquired a slight hoot. A minor thing, to be sure, but one that did ultimately detract from the music.

Of more immediate concern on piano recordings was a slight feeling of disconnection between the transient starts of treble notes and the body of their tone, the former sounding more forward in the soundstage. There was also some emphasis of LP surface noise, while the jingles on David Chesky's tambourine on the depth test track on the Chesky jazz sampler (JD37) floated in front of the instrument's image. This didn't sound like a mismatch or a hole between the drive-units at crossover—the two units seemed superbly integrated—but rather as if the tweeter was about 1 or 2dB too sensitive given the 15's ultimately rather lean low frequencies.

Stereophile's German correspondent Markus Sauer was visiting Santa Fe over Easter; listening to the Studio 15s reminded him of the French "Rule of 400,000": the product of the high and low –3dB points of a speaker's response should equal 400,000. If the bass extends down to 20Hz, then the treble should reach 20,000Hz; 20 x 20,000 = 400,000. If the speaker extends no lower than 40Hz, then the treble should roll off earlier, by 10kHz; 40 x 10,000 = 400,000. This is a bit extreme, in my view, but it is generally true that, for subjective satisfaction, the more lean a loudspeaker's bass response, the more restricted its highs should be. (An excellent example of this philosophy is the Spica TC-50, which sounds balanced overall despite its very lightweight lows.) Despite its identical drive-unit complement, Monitor Audio's own Studio 20 also sounded better balanced in the treble than the Studio 15, due to it digging down in the bass another 11Hz.

There was also a slight degree of "bite" in the 15's mid-treble, presumably due to the woofer's primary breakup mode. This was not always very important sonically, though it did render the speaker very fussy over matching equipment. It sounded much better balanced with LP source than with CD, for example, the latter tending to sound rather relentless in the mid-treble. The MIT interconnect which sounds so terrific with the WATTs/Puppies was too grainy in the treble compared with AudioQuest Lapis on the Monitors. Similarly, the 15 was a better partner for the VTL D/A processor than the PS UltraLink. Though both sounded rather forward in absolute terms, the tubed D/A proved a more synergistic combination with the Studio 15's own rather glarey mid-treble.

Higher in frequency, the top octave and a half was silky and delicate, airy and spacious. No problems there. In fact, the Studio 15s resembled the more expensive Studio 20s in their excellent portrayal of recorded space. On naturally miked recordings—as I write this on the laptop, for example, I am enjoying the excellent 1986 Nimbus recording of Mendelssohn's "Italian" Symphony with the Scottish Chamber Orchestra (NI 5067)—not only can you hear deep into the soundstage, but that stage seems totally disconnected from the physical reality of two loudspeakers sitting before you. You can hear the "slap" of the sounds of instruments from the walls of the hall. Even with artificial reverberation, such as the repeat echo effect on Ulla Meinecke's track "Die Tänzerin," from her second LP Wenn Schon Nicht Für Immer Dann Wenigstens Für Ewig (German RCA PL70932), the 15s' superbly transparent midrange and huge soundstaging ability let me revel in the reverberation tails. But as Markus Sauer noted, the higher-frequency echoes seemed to be significantly stronger than those in the bass and midrange via the Studio 15s, something that was not true when the same track was played on the Celestion 100s or even the Wilson WATTs/Puppies, which are hardly reticent in the treble.

The LEDR test tones on the Chesky CD confirmed this imaging ability, though frontal images were slightly broader than I have heard from the very best space-meisters.

Conclusion
With rather a lean overall balance and a degree of forwardness in the mid-treble, Monitor Audio's Studio 15 is unforgiving of the components with which it is to be used. With careful system building, however, it will prove capable of giving an intensely detailed, vivid, superbly spacious sound, particularly when coupled with a high-end LP source. However, there is no getting away from the fact that it is expensive at $3500/pair, not even considering that good stands are essential to getting the best from it. For example, with stands it costs 30% more than the excellent, more–full-range Spendor S100 I reviewed last December. In fact, the price of a pair of Studio 15s with their ST-15 stands is even within striking distance of Monitor Audio's own Studio 20: $4374 vs $4499. Given the fact that the latter are floorstanding, make no greater demands on placement, go usefully lower in the bass, and are desirable pieces of furniture in their own right, this makes the Studio 15 rather uncompetitive. If what these speakers do right fits your own sonic priorities, my advice is to listen to both for yourself and make your own decision. I have to say, however, that, based on my listening to it in Robert Harley's system, I would choose the Studio 20.