Monitor Audio Monitor 7 loudspeaker John Atkinson
Sam Tellig, Stereophile's Audio Anarchist, didn't hold back in his praise of Monitor Audio's miniature Monitor 7 loudspeaker ($379/pair) in the January issue. "Very fine speakers for the price," he gushed. He was even going to give a pair to Mrs. Anarchist for Christmasso much cheaper than something from Tiffany's!but then fate intervened, both his samples emitting a "rattling sound," apparently due to the plastic port inserts coming loose. As his initial impressions were so positive, however, I decided that the 7 should undergo the full review treatment here in Santa Fe.
Finished in a neat black "lacquer," the Monitor 7 is a two-way design, with the diminutive 4.5" dopedpulp-cone woofer loaded by a 1.25"-diameter reflex port, 2.5" deep, on the rear panel. The woofer also has a butyl rubber surround. In common with Monitor Audio's overall philosophy, the 19mm tweeter is an aluminum-dome type, with the voice-coil former made in one piece with the dome. Though sourced, I believe, from the Norwegian SEAS company, the tweeter is unique to Monitor Audio and is cooled with ferrofluid. Neither unit is rebated on the front baffle. The crossover is minimal, consisting of four components glued to the rear of the terminal panel. (Unusually for an English speaker, this accepts standard dual-banana plugs.) A ferrite-cored inductor in the woofer feed provides a first-order low-pass action, while a series plastic-film capacitor and a shunt air-cored coil make up a second-order high-pass filter for the tweeter. The fourth component is a series resistor to lower the tweeter's sensitivity a little.
Unusually for a speaker in this price range, the cabinet is constructed entirely from MDF (medium-density fiberboard).
Whereas the last two miniature speakers I've reviewed, the Cambridge SoundWorks Ambiance elsewhere in this issue and the Celestion 3 (see the October 1989 issue, p.161), are intended to be used relatively close to a room boundary, the Monitor 7 I understand to be more of a free-space design. Accordingly, I initially sited them on 24" Celestion stands (footnote 1) some 6' from the sidewalls and 3' from the rear wall. The cloth-on-frame grille presents significant obstruction to the tweeter, so I left it off for the auditioning. In any case, the fact that the front baffle is nicely finished suggests that the manufacturer also intends the speaker to be listened to sans grille.
As with the Ambiance, low bass was missing in action, and I felt that moving the speakers a little nearer the rear wall provided some useful body to the sound. This still didn't make the 7 a suitable candidate for organ recordings. Peter Mitchell's recording of Harvard's Busch-Reisinger Museum instrument on the Stereophile Test CD had insufficient pedal weight to support the music effectively. Trying to drive the speakers to high levels with music having continuous bass energy, your average rock recording for example, also proved disappointing in that it was relatively easy to make the rear port "chuff," and the midbass developed an increasing sense of sogginess as the level got higher.
With that proviso, however, my initial impressions of the Monitor 7 were very favorable. Its sound was bright, open, and appealing, with a good sense of space noticeable around instrumental images. It was also appreciably more dynamic than the Cambridge SoundWorks speaker. I can see why the Anarchist liked the 7 so much, its soundstaging having that sense of palpable presence, of believability, that he finds so important in reproduced music.
J. Gordon Holt's purist recording of the Järnefelt Praeludium on the Stereophile Test CD showed that the 7s created a better sense of depth than the Ambiances when sited in the same positions, though neither speaker could compete with the BBC LS3/5A in this respect. In addition, instruments with a lot of treble energy were pushed forward in the soundstage rather more than I felt appropriate. The Chesky LEDR tracks (footnote 2) revealed the 7s to produce a more stable sense of lateral imaging than the Ambiances, though less of a sense of image height was developed with the "Up" and "Over" tracks (footnote 3).
Tonally, the midrange seemed relatively uncolored for a budget-priced speaker, individual instrumental colors emerging relatively unscathed. The different colorations on the Stereophile CD's microphone test track were significantly easier to differentiate than they were via the Ambiances or Celestion 3s, for example. Higher in frequency, things were less good, though. The piano's right-hand registers were too clangy, while female voice took on a touch of hardness or stridency above the treble staff. The HF air and sparkle that had initially impressed me could easily become fatiguing; there was also some emphasis of recorded tape hiss compared with the Ambiances and Celestions, and the Hildegard of Bingen recording was reproduced with rather too dry, too throaty a tone color.
Apart from comparisons with the Cambridge SoundWorks Ambiance, I carried out some comparative listening sessions with the almost identically sized but less expensive Celestion 3. The Celestion had more midrange coloration noticeable than the Monitor, recorded piano and lower strings acquiring a cardboardy character by comparison. It also sounded more shut-in in the top two octaves. Conversely, the Monitor tended to sound rather shouty in the low treble, with an exaggerated brightness region. The Celestion will undoubtedly be kinder to inexpensive electronics, which often feature a brightness similar to that of the Monitor Audio speaker. Those differences apart, the speakers tended to be rather similar, with almost identical sensitivities, subjective bass extensions, and imaging precision. Despite its brightness, however, the more expensive speaker gets the prize on points in my opinion, due to its more musically believable presentation.
With its open, appealing tonal balance, relatively uncolored midrange, palpable soundstaging, excellent finish, and relatively low price, Monitor Audio's Monitor 7 should sell well. However, its lack of low frequencies seems to be more of a subjective problem than with either of the sealed-box speakers with which I compared it, the Cambridge SoundWorks Ambiance and the Celestion 3. In absolute terms, I also found its treble to be both bright and rather hashy (footnote 4), and its tonal balance will be unforgiving when it comes to choosing matching electronics and source components. Recommended, but be sure to audition the Monitor 7 carefully to ensure that its treble will not drive your overall system balance too far in the brightness direction.
Footnote 1: The stands were the same that I used for my review of the Spica TC-50 and Celestion 3 last October, $300/pair Celestion SLSi models which are single-pillar designs, with steel top and bottom plates. The pillars are filled with 25 lbs of lead shot, topped up with about another 10 lbs of dry sand. The top plate is a little large for the Monitor 7s, so I positioned the speaker at its front edge, coupled to the stand with small blobs of EZ-Tak.
Footnote 2: "Take Me to Your LEDR," Vol.12 No.12, p.82. The test signals are based on pyschoacoustic research carried out at Northwestern University into how the ear/brain localizes sound sources.
Footnote 3: Having tried this test on about 10 pairs of loudspeakers as of the time of writing, it seems that the smaller loudspeakers do better with this aural illusion, as do those with first-order crossovers. The larger a speaker's front baffle and the higher the order of its crossover, the less the image rises above the speaker position.
Footnote 4: I am told that the more expensive Monitor 9 features a version of Monitor Audio's excellent aluminum/magnesium-alloy 1" dome tweeter. This speaker may well solve the 7's treble problems while preserving its virtues. But don't quote me on that.