Sonus Faber Amati Futura loudspeaker
The form factor has remained unchanged since 1999: a slim, tall, three-way tower speaker with immaculately finished and veneered side panels of wood, horizontal strips of black ebony inset under the lacquer, a leather-covered front baffle, and a lute-profiled enclosure constructed from horizontal layers of maple of varying thicknesses joined with a polymer glue that provides internal damping and reinforced with internal ribs, the package completed with Sonus Faber's traditional vertical-string grille. However, the top and bottom of the speaker now comprise silver-colored metal plates machined from a proprietary alloy (primarily aluminum and copper) called Avional, plated with nickel, finished to mirror smoothness, and engraved with the company's name. The narrow rear of the speaker now ends in vertical fins of the same nickel-plated metal. And the price has inevitably risen, to $36,000/pair.
Inside that gorgeous enclosure and its seven coats of hand-rubbed nitrocellulose lacquer, the Futura represents a complete reworking of the earlier Amatis, with some of its technology trickled down from a flagship speaker, The Sonus Faber, of which only 30 pairs would be made at $200,000/pair, and which was shown to the US press at the 2011 Consumer Electronics Show. Art Dudley discussed this technology in detail in his January 2011 review of the stand-mounted Sonus Faber Guarneri Evolution speaker, so I'll merely summarize it here.
In particular, to control cabinet vibrational resonances, there is now a mass-damping system. The Amati Futura's top and bottom plates are held under tension by a metal rod, to which have been attached concentric metal discs tuned to cancel the cabinet's primary internal mode. Internal ribs are also placed so as to minimize resonant modes. The alloy bottom plate is bolted to a second metal plate with large compliant washers, to provide a degree of mechanical isolation; carpet-piercing cones front and rear screw into four studs that protrude from this second bottom plate. The front cones are taller than the rears; all can be adjusted to change the backtilt of the Futura's front baffle.
The previous Amati Homage's ring-radiator tweeter has been replaced by a 1.1" soft-dome tweeter described as an "ultra dynamic integrity classic Ragnar Lian" driver, Ragnar Lian being one of Sonus Faber's cofounders. Mounted immediately below the tweeter and operating from 220Hz to 3.3kHz is the 7" midrange unit, custom-made by ScanSpeak; this has a large, 42mm-diameter voice-coil and a large rubber roll surround to maximize power handling, and uses a cone formed from "real time air dried and non pressed cellulose fiber" rather than the Homage version's polymer, with a concave metal phase plug. The motor system incorporates "triple Kellogg/Goeller" copper shorting rings on the voice-coil's Kapton former to reduce distortion. The midrange unit is mounted in its own subenclosure, which vents to the rear between the Avional fins. The port is lined with foam to reduce wind noise, a technology Sonus Faber calls Stealth Reflex. Both the tweeter and the midrange unit are mounted on a decoupled subbaffle.
The two vertically arrayed 8.75" woofers operate below 220Hz and are each loaded by a Stealth Reflex port between the rear fins, the ports placed just above the speaker's terminal panel. Each woofer has an aluminum-magnesiumalloy cone damped with elastomer foam, and a concave metal phase plug, the cone powered by a long-throw "controlled eddy current" voice-coil 1.5" in diameter. The lower woofer is rolled off earlier than the upper, to reduce the overall radiating area in the lower midrange.
The complex crossover is said to feature "progressive slopes" and is realized with Mundorf Supreme capacitors and Jantzen inductors. Electrical connection is via two pairs of high-quality binding posts at the bottom of the rear panel, between the metal fins. These are connected with straps; for single wiring, Sumiko recommends that the speaker cables be connected to the upper pair of posts.
Overall, the Amati Futura is perhaps the most graceful-looking speaker I've had in my listening room. My only concern was the mirror-finished top plate and fins, which, despite my attempts always to remember to use the supplied white cotton gloves, acquired a patina of palm prints.
As he had with other Sonus Faber speakers I've reviewed, Sumiko's John Hunter helped me set up the Amati Futuras in my room. Also as he'd done in the past, he relied on Jennifer Warnes and Rob Wasserman's recording of Leonard Cohen's "Ballad of the Runaway Horse," from Wasserman's Duets (CD, MCA MCAD-42131, footnote 1). Having first found the best places for each speaker, moving each one half an inch or so until he'd deemed balanced the integration of its low-frequency and lower-midrange outputs on Wasserman's bass, Hunter then toed-in the speakers to the listening seat, and adjusted the rake of the front baffles with the cones until the image of Warnes's contralto was optimally focused and tonally correct. He then left me to my listening.
Needless to say, I had no desire to hear "Ballad of the Runaway Horse," or even Jennifer Warnes, for quite a while. Instead, I played the pink-noise track from Editor's Choice (CD, Stereophile STPH016-2). Moving my head up and down as this signal was played revealed that it's important to sit with one's ears on the Amati Futura's optimal axis. I heard small changes in the "vowel" character of the pink noise as I moved my head slightly up or down; these disappeared when my ears were exactly on the correct axis. However, the speaker didn't sound colored until I stood up, when its sound acquired a distinctly hollow-sounding nature.
I mostly preferred the balance with the grille in place, particularly with the crisp-charactered MBL Reference 9007 monoblocks, but the Futura did sound its most transparent without the grille, easily letting me perceive the sonic differences between the Bricasti, dCS, and Weiss D/A processors that I wrote about in the February issue.
When I played the half-stepspaced toneburst track on Editor's Choice, the tonebursts spoke very cleanly down to this track's 32Hz limit. Repeating the track while I listened to the cabinet walls with a stethoscope revealed almost no spurious resonances other than a slightly live nature between 200 and 300Hz. The 1/3-octave warble-tone tracks on Editor's Choice sounded quite even from 300 to 63Hz, a little lower in level at 50 and 40Hz, and returned to full level at 32Hz, which is close to the lowest-frequency resonance in my room. The 25Hz warble tone was still audible, but the 20Hz tone was not. There was also no chuffing noise audible from the ports.
Footnote 1: Visiting a Listen-Up store in Colorado in May 2011 for a "Music Matters" evening, I knew which room was being set up with Sonus Faber speakers even before I stepped into it, from the sound of "Ballad of the Runaway Horse" leaking though the door.