Sidebar 3: Measurements
The Studio 15 is a pretty easy speaker to drive, as revealed by its plot of impedance amplitude and phase (fig.1), which drops below 8 ohms only between 110Hz and 800Hz, and in the region of the port tuning frequency of 55Hz. The ultrasonic tweeter resonance reveals its existence by the blip at 25kHz, and there is a faint hint of a wrinkle in the amplitude plot at 500Hz, indicative of possible cabinet resonant problems in this region.
Fig.1 Monitor Audio Studio 15, electrical impedance (solid) and phase (dashed). (2 ohms/vertical div.)
The…
The idea of mating a dynamic woofer to a ribbon midrange/tweeter is appealing on paper. Such a "hybrid" loudspeaker would have the many advantages of a dipole ribbon transducer, yet be more practical and affordable than full-range ribbon designs. Among the ribbon's great strengths is its narrow vertical dispersion (reducing the ceiling and floor reflections), contributing to the ribbon driver's well-deserved reputation for transparency, terrific soundstaging, transient zip, and excellent resolution of detail. By adding a dynamic woofer to a ribbon midrange/tweeter, the system cost can be…
I experimented with placement after Jason left, but ended up with the Slant 6es where he had left them: 60' apart (inside edge to inside edge), with the rear of the woofer enclosures 43" from the rear wall, and a listening distance of 11' (listening position to a point between the loudspeakers' front baffles). Very little toe-in was needed to bring the loudspeakers into focus—too much toe-in, or none at all, reduced image specificity and affected the tonal balance.
Adjusting the rake angle is easy with the long front spikes and the short rear spikes—I tilted the 6es back considerably…
Sidebar 1: Specifications
Description: Two-way, reflex-loaded dynamic/ribbon hybrid loudspeaker. Driver complement: One 6.5" cone woofer, one 26" dipole ribbon. Crossover frequency: 1kHz. Recommended amplifier power: 50Wpc minimum, 200Wpc maximum. Nominal impedance: 6 ohms, 4 ohms minimum.
Dimensions: 14.5" W by 52.5" H by 14.24" D. Weight: 80 lbs each. Enclosure: 24 liters (0.8ft3).
Serial numbers of units reviewed: 001712/001713.
Price: $1995/pair (1995); no longer available (2008). Approximate number of dealers: 125.
Manufacturer: Apogee Acoustics, Inc., Randolph, MA 02368…
Sidebar 2: System
I used two amplifiers to evaluate the Slant 6: the $12,000/pair reference-quality Audio Research VT150 tubed monoblocks, and the $2355, more real-world McCormack DNA-1 Deluxe (see my Follow-Up elsewhere in this issue). Loudspeaker cables included 3' bi-wired runs of AudioQuest Dragon/Clear, and an 8' bi-wired pair of Symo—the Apogee-recommended cable for all Apogee loudspeakers. When Jason was visiting, we heard significant differences between cables—the Slant 6 appeared to be very cable-sensitive. I ended up doing most of my auditioning with the bi-wired Symo set, both…
Sidebar 3: Measurements
John Atkinson measured the Slant 6 in Stereophile's test lab and presented the graphs to me after I'd completed the auditioning and written the rest of the review.
The 6's calculated B-weighted sensitivity was 83.2dB for a drive level of 2.83V at 1m—a rather low value. The impedance plot (fig.1) shows a minimum impedance of 3.78 ohms at 120Hz—with a 4 ohm dip at 2kHz—and an impedance of less than 5 ohms above 1kHz. The port tuning can be seen as the impedance dip at 37Hz, implying reasonably good LF extension.
Fig.1 Apogee Slant 6,…
One question posed by John Atkinson at the July 1991 Stereophile Writers Conference had to do with the ease of reviewing: Is it harder to write a bad review of an expensive product than a good review? I find it hardest to write a good review of an inexpensive product. If I admire a less expensive loudspeaker, for example, it may become a recommended component, and can displace a more expensive speaker (that received mixed comments) from our twice-yearly rankings. This can be a big responsibility; even a conditional rave of a low-cost product means that JA may assign another Stereophile…
The Snell E/IIIs made a definite impression right away, and a good one. Despite their size, the E/IIIs came alive in my listening room, with a big soundstage presentation, a slightly forward quality, and no harshness or roughness. The speaker conveyed the warmth inherently present in music, while being open, fast, and showing considerable deep-bass extension. This warmth added a slight richness to the sound that I found very pleasing, particularly on well-recorded piano music. Chopin's Nocturne, Op.62 No.1, as played by Vladimir Horowitz (Last Recording, Sony SK 45818, DDD), came alive with…
Sidebar 1: Specifications
Description: Two-way, reflex-loaded, floorstanding loudspeaker. Driver complement: one 8" cone woofer, one 1" treated textile-dome tweeter, one 0.75" soft-dome, rear-firing tweeter. Crossover frequency: 2.7kHz, 24dB/octave slope. Frequency response: 39Hz–20kHz, ±1.75dB anechoic (response specified on-axis or up to 15° off the horizontal axis). Nominal impedance: 6 ohms. Sensitivity: 91dB at 1W (2.83V) at 1m, anechoic (sensitivity higher in a normal environment). Power requirements: suitable for use with amplifiers rated from 20Wpc to 100Wpc.
Dimensions: 13" W…
Sidebar 2: Review System
Amplifiers included a Mark Levinson No.27 (used exclusively with the Quad ESL-63 USA Monitors) and a Krell KSA-250. In addition, I used a very inexpensive Lafayette Criterion SR 10A receiver, just to test Kevin Voecks's suggestion that the Snell Type E/IIIs could also perform with lesser electronics. The Quads and the Snell A/III's midrange/tweeter section were driven by the Levinson No.27 via 15' runs of Monster Cable. Because the two systems were bi-amplified, the Quad/Gradient subwoofer and the A/III's woofer section were driven by the Krell KSA-250 via HF10C…
