LOUDSPEAKER REVIEWS

 AUSTRALIAN HIFI MAGAZINE

BEST BUY REVIEWS 1994

The following review comes from Australian HIFI in 1994.

Transcript of Review by Greg Borrowman, Editor of AUSTRALIAN HIFI.

It's not right to judge a book by its cover, and by the same token it's probably not right to judge a speaker by its veneer. It is often the case however that a manufacturer who is particular about fits and finishes may also be equally obsessive about the more important matters of component selection and circuit design. And obsessiveness in loudspeaker design is by and large the preserve of the smaller specialist manufacturers who, though they haven't the engineering and test facilities of the big players, more than make up for their lack of high tech resources by zealous attention to detail. However, these days, thanks to the dwindling cost of computer hardware and the increased availability of packages such as MLSSA and LEAP, Calsod etc, even the smallest manufacturers can afford the tools of the modern loudspeaker designers' trade.

Sonic Arts' Minitor Pro speakers are available in either black vinyl wrap, or as in the case of the pair supplied for review, a lustrous genuine Jarrah veneer. Jarrah is a handsome material, and Sonic Arts' cabinetmaker has done it justice. I happen to prefer to listen to my speakers with the grills off, and it was a pleasant surprise to find that not only are the sides veneered, but so too is the front baffle. In fact the only surface not graced with Jarrah is the bit you shouldn't see, the rear baffle.

Speaking of the rear baffle, the Minitor Pro back panels feature a bass-reflex port and a chunky pair of four way binding post terminals inset into the customwood. The latter are substantial enough to cope with all but the most hawser-like of unterminated cables.

According to the designer a great deal of time was spent experimenting with various enclosure dimension ratios in order to find just the right mix to work with his crossover network and drivers. What he ended up with is a box that has a narrow front baffle but is comparatively deep. Rogers' avowed purpose is to create a speaker that as closely as possible reproduces the experience of live performance and by keeping the surface area of the front baffle to a minimum, to maximize the systems' imaging capabilities.

To reach his very worthy goal, Rogers has selected a 127mm woofer from Danish loudspeaker giant Vifa. According to Rogers, it's a variant of Vifas' C13WG. The driver as you may be able to see from our photograph, is inset into the baffle. Its diameter at the soft rubber surround is approximately 110mm and the rigid coated cone measures 95mm across. This gives the woofer an effective cone area (ECA) of 71cm squared. The basket is a pressed steel affair and boasts a substantial motor assembly. The tweeter comes from that other Danish manufacturer, Dynaudio and is that company's well-regarded D21/2. A 19mm unit, its soft fabric dome is driven by a ferrofluid damped hexacoil voicecoil. Inside the 170 by 260 by 240mm (W by H by D) cabinet there is a quantity of fiberglass material for damping purposes. The crossover is linked to the drivers via high quality silver cable, and all connections are soldered. In sum everything inside the speaker is as neat, tidy and professional as its attractive exterior. The Minitors have nominal impedance of 8 ohms and an efficiency rating of 87dB SPL for 1 watt at 1 metre. Rated power handling is 70 watts RMS per channel and the frequency response is said to extend from 45Hz to 20kHz + 3dB.

 

LISTENING SESSIONS

Sonic Art recommends that these speakers be placed approximately 75mm from the wall if they're sited on a bookshelf. However the ideal placement is on stands that position the tweeters at the listeners' ear level and give the boxes at least a metre's clearance from the nearest boundary. Our listening tests were conducted first with the speakers mounted in this fashion and then with the speakers mounted on a shelf. In the shelf position the speakers were approximately 1.8m apart, 80mm away from the rear wall and a metre from each sidewall. In both locations the listening position was about two metres from the plane of the front baffles and tweeters were just above ear height. The amplifier used was rated at 100 watts RMS per channel, both channels driven into 8 ohms.

We kicked off the listening tests with the title track from Neil Youngs' Harvest Moon (Reprise 9362 45057-2) The listening room is on the lively side and this often has the effect of exaggerating the brightness typical of many small speaker systems. However the Sonic Art Minitor Pros immediately announced themselves as atypical.

The first impression was of a very open, relaxed and smooth sound. The Minitors carry the Pro appendage because they are designed to deliver the response and dynamism of professional monitors. The Minitors' pleasant sweet character, however is unlike most monitors I have heard. The average studio monitor is so clinical and uncolored that many ordinary listeners find the sound slightly unpleasant. Audio engineers need access to every nuance and detail of a recording, but in my experience most non-audiophiles prefer a little honey in the mixture.

What the Minitor Pros manage to do quite successfully is to mix the access to detail and dynamics of a superior studio monitor with the more musical flavour of a well-made bookshelf speaker. The detail of a performance is there, but it is not necessarily thrown into sharp relief because the sound leans away from the clinical and hard and toward the warm and smooth. Perhaps as a consequence of this, they seem particularly suited to female vocals. American singer Suzy Bogguss (Voices in the Wind, Liberty CDP-0777-7-98505-2-1) has that familiar soft twang of so many country artists and given the wrong speakers. Her voice can sometimes sound overly nasal. The Minitor Pros seem incapable of inflicting such unflattering treatment and Suzys' cover of John Hiatts 'Drive South' has never sounded better.

Along with transparency and dynamics, the test of any speaker is its' capacity to recreate a plausible soundstage. Thanks to their generally open quality, the Minitor Pros were up to the mark in this category as well. The breadth of the sonic pictures extended well beyond the boxes themselves and the apparent height of the image was well above average. The depth of the image was compromised in the shelf-mounted position, but on stands the image depth was fabulous, easily able to contain a full orchestra and still position the tympani at the rear of the stage.

 

CONCLUSION

SonicArt may only be a fairly recent entrant to the Australian loudspeaker fraternity, but it is clear that the designer not only understands the technical side of speaker design, but that he also has a real feel for what must be done to elevate a speaker above the ordinary. An impressive effort and an extraordinary loudspeaker!