Audio Physic Avanti III loudspeaker Page 2

While the latest generation of 5" SEAS aluminum-cone drivers attracted Gerhard's attention for the Avanti III's midrange, resonances at the top of the frequency range made such drivers unacceptable—until the design duo of Gerhard and Diesterich began to apply various materials at different tensions to the cone's underside circumference, where it attaches to the surround. During my visit to the Audio Physic factory, I watched and listened as various materials, including plain old rubber bands, were applied to the cones. The results were dramatic—even when the raw driver, sitting on a test bench, was driven by a portable transistor radio. Unmodified, the driver had a characteristic "pinging" sound. Modification in place, the "ping" was gone.

Ultimately, AP developed a material and an application methodology, Active Cone Damping (ACD), that SEAS now incorporates in its manufacturing process—but only for drivers destined for Audio Physic. The midrange driver used in the Avanti III is a heavily modified version of SEAS's original design.

The Avanti III uses two pairs of side-mounted, dual-ported, floor-firing 6½" Peerless woofers (for a total of four woofer per speaker) in push/push configuration, as originally introduced on the first Avanti. Side mounting allows for a narrow, graceful front baffle, and AP claims the driver placement helps equalize pressure on the cabinet walls for lower distortion and better dynamic performance.

The crossover points are 200Hz (6dB/octave), 500Hz (6dB/octave), and 2.2kHz (18dB/octave). Why three points? Because the amount of radiating surface required increases as the frequency decreases. The dual midrange drivers are not there to double the midrange energy. The design uses the lower-midrange driver only in the narrow band between 200 and 500Hz, while the more powerful upper-midrange unit, fitted with dual magnet assemblies, covers 200-2200Hz. The radiating area is thus increased in the lower midrange without encumbering the rest of the response range with unnecessary mass.

The compact, curvaceous cabinet, sourced from a Danish company that builds enclosures for many big-name speaker companies (some of which make their own drivers), is both aesthetically pleasing and technologically advanced. It's surprisingly light, yet extremely rigid and well-damped. The midrange drivers and tweeter occupy isolated chambers within the raked cabinet, which is extensively braced and rounded at the rear to avoid the parallel surfaces that can induce standing waves. A slanted (7 degrees), dual-layer baffle features a front panel of solid, laminated wood specially contoured to minimize diffraction and refraction. This panel's complex design is the result of the patented Hornflex process, which uses a computer program to transfer the three-dimensional shapes onto the two-dimensional patterns used in the actual manufacturing process. The speaker's rear is fitted with a single pair of gold-plated binding posts. A biamping option of dual pairs of posts is available at extra cost.

Setup
Contrary to a popular misconception, Audio Physic speakers are not specifically designed for nearfield placement and listening, though the setup procedure outlined on Immedia's website is recommended, and works well for other loudspeaker brands as well. Though I listen in the nearfield because of how my room is configured, I was unable to set up the Avanti IIIs using Audio Physic's methodology. Instead, I placed the Avantis where the Sonus Faber Amati Homages usually reside (9' apart, 8' from the listening position, 2½' from the sidewalls, and about 2½' from the front wall), then moved them slightly forward to account for the acoustic center of the side-mounted woofers. I ended up with the speakers toed-in so that the tweeter axes crossed just behind my head.

As with the Virgo or any other revealing speaker, setup of the Avanti IIIs proved critical in maximizing high-performance results. Tiny changes in placement yielded enormous sonic differences, especially when it came to locking in the incredible image focus and soundstaging precision these speakers were capable of delivering. Of course, you never know how well a pair of speakers can perform until you try to improve on what you've already achieved. Sometimes you've already reached the upper limit of a product's performance capabilities and are wasting your time. In the case of the Avanti IIIs, I thought I'd maxed them out only to find that I could take them a step further. I also found that the speakers were ruthlessly revealing of a cartridge's vertical tracking angle (VTA) and other minutiae of analog setup.

The narrow Avanti III sits on a pair of metal stabilizer cross-braces with circular feet at each end. Port clearance seemed insufficient on my Berber-carpeted floor using the short threaded points supplied, so I asked and quickly received a longer set. It's a cultural issue: Apparently, Europeans mostly have area rugs and set the speakers on hardwood floors, which is why AP also supplies tiny, cupped, felt-bottomed feet.

Listening
I ended up having the Avanti IIIs for two extended periods of time, before and after HE 2001. After three weeks of extensive listening, I had to ship them to New York City, where they were used in one of the Sound By Singer rooms at the Show, driven by Hovland electronics, an Accuphase CD player, and an Immedia RPM-1 turntable with RPM-2 tonearm and Helikon cartridge. Aside from the amplifier, turntable, CD player, and cables, Show attendees got to hear a reasonably close approximation of my review system, including electronics, tonearm, and cartridge. If you heard AP's system at HE2001, you got a taste of what I've been hearing for well over a month. Yummy.

I got to spend the first day after the Show at home with the new Hovland Sapphire tube amp. Even under lousy Show conditions, that system had sounded very musical to my ears. At home in my acoustically tweaked room, the Avanti IIIs, driven by all-Hovland electronics, sounded even more impressive. I spent the rest of the month with the Avanti IIIs driven by my reference Musical Fidelity Nu-Vista 300 power amplifier.

COMPANY INFO
Audio Physic
US distributor: Immedia
1717A Fourth Street
Berkeley, CA 94710
(510) 559-2050
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