Pioneer Elite Reference Loudspeaker System (SGHT Review) Page 2

The spherical enclosure is no gimmick; the shape produces the lowest possible diffraction (unwanted reflections from the edges of the enclosure). The IRIS is mounted so that it can be rotated to fine-tune the imaging—and, in theory, eliminate the need to toe-in the speakers.

Users should exercise caution when rotating the IRIS to avoid touching the midrange diaphragm. I did so a few times without causing any apparent damage, but the diaphragm is quite vulnerable. If your environment exposes the IRIS drivers to the risk of damage (or you prefer a less esoteric look), you might want to leave the furnished grilles in place. I did all my listening with the front three speakers' grilles removed.

Frequencies between the subwoofer's 120Hz upper rolloff and the IRIS's 450Hz lower limit are reproduced by a 6.5" midrange driver with a lightweight, injection-molded cone. This driver is concealed directly behind a nonremovable grille. The sloped baffle just behind the IRIS is simply the grille cloth on its frame.

The advantage of this arrangement is that all frequencies above 120Hz come from approximately the same area, with little lateral displacement of the drivers. This should result in more consistent horizontal and vertical radiation patterns than most multiway speakers. However, the midrange driver sits in a shallow well with its front partially obstructed by the IRIS. I was concerned that this arrangement might cause audible coloration in the midrange, but I heard no obvious adverse effects.

The TX-F700's cabinet consists of gracefully curved, multi-ply panels with internal bracing. The knuckle-rap test suggests that the side panels are not unusually thick (the speaker's 60-pound weight hints at this), but they appear to be well damped. Only by striking the enclosure with my ear pressed against it could I hear a slight resonance, which died away quickly.

The TZ-C700 center channel also contains a centrally mounted IRIS driver, which is flanked by a pair of 5.25" woofers. These woofers are powered in the same fashion as the left and right speakers, but they cross over at 450Hz. While the TX-F700 contains a real subwoofer, the woofers in the TZ-C700 don't extend deep enough to justify such a classification; they're just woofers. As a result, the Pioneer center should be driven as a "Small" center speaker (ie, with the receiver's or surround processor's center-channel high-pass filter engaged).

I'm not sure why Pioneer made the TZ-C700 an active speaker; it's possible that some bass/midrange contouring is performed by the internal amplifier. There's no way to adjust the TZ-C700's woofer level, which might have allowed the user some control over the timbre of the upper bass/low midrange.

The IRIS enclosure in the TZ-C700 center channel does not rotate, and only its visible, outer portion is rounded; the internal enclosure for the center-channel IRIS is tubular. The woofer's port is visible at the front of the main enclosure (along with a small port for the IRIS midrange). The two woofers are individually covered with grille material; even au naturel, the TZ-C700 has high-tech style. To protect the IRIS midrange diaphragm, you can use the large removable grille, which covers the entire front of the speaker. I didn't.

According to Pioneer, the TZ-C700's enclosure is molded from an antiresonant, engineering-grade resin. The word "resin" covers a lot of ground, from simple plastics to various types of rock- or marble-like materials. (Those hard, synthetic countertop materials, such as Dupont Corian, are resins.) The TZ-C700's enclosure is definitely not rocklike, but it is nevertheless reasonably solid and well-damped.

The TZ-S700 surround speaker is considerably different from the two front designs. It's a two-way system; there's no IRIS driver, simply a single small woofer and tweeter. The only unusual aspect of the surround's design is the rotatable tweeter, which lets you choose direct radiation or slight diffusion of the high frequencies, depending on where you aim it.

The drivers are located behind a metal-screen grille, but the tweeter can be rotated with the grille in place with a large plastic bolt at the enclosure's top. The metal grille can be removed to access the two holes for mounting the enclosure on the wall, but most owners will likely leave it on during use. I found no advantage in removing it; the surrounds were the only speakers in the Pioneer package that I used with the grilles on.

The TZ-S700's enclosure is also molded, presumably of the same material used for the center channel. Of the three speakers in the Elite Reference system, only the TZ-S700 is finished in white; the TZ-F700 and TZ-C700 are available only in black. The TZ-F700 would look striking with some sort of wood finish on its sides and back, but that would probably increase its cost considerably. And the speakers would then not match Pioneer's PTVs, which was obviously a design goal.