TAD Compact Reference CR1 loudspeaker
Andrew Jones designed some superb-sounding speakers for Pioneer, including the S-1EX, which Kal Rubinson enthused over in the March 2007 issue of Stereophile; and, more recently, the SP-BS41-LR, which, said Robert J. Reina in his September 2011 review, offers astonishingly uncolored sound quality for just $150/pair.
But it has been two Jones designs for Pioneer's Technical Audio Devices Laboratories division (TAD) that have attracted the press's attention at recent audio shows, both designed with no apparent limit on the bill of materials: first the floorstanding Reference One ($78,000/pair), then the stand-mounted Compact Reference CR1 ($37,000/pair plus matching stands for $3600/pair). I couldn't envisage how I'd be able to get a pair of 350-lb Reference Ones down the steps into my basement listening room. But the Compact Reference weighs a more manageable 101.4 lbswhen I visited the TAD room at the 2011 Consumer Electronics Show last January, I asked Jones for review samples.
Andrew Jones had worked on the groundbreaking Uni-Q drive-unit when he was at KEF, which mounts a dome tweeter on what would have been the midrange unit's dustcap at the center of its cone. The benefit of this is that the acoustic centers of the midrange unit and tweeter coincide, and their directivities can be made to match in the crossover region. There are therefore no discontinuities in the speaker's radiation patternno off-axis flares or gullies that can lead to coloration, even when the on-axis output is flat. The trade-offthere are always trade-offsis that the symmetrical acoustic environment for the tweeter means that diffraction effects from the boundaries of that environment all occur at the same frequency. Minimizing these effects requires that special attention be paid to the profile of the midrange cone.
All of the TAD Reference speakers' drive-units are made by TAD. The midrange and treble are handled by what TAD calls the Coherent Source Transducer (CST). As shown in the exploded diagram on the next page, this is a concentric driver combining a 6.5" midrange unit with a 1.375" tweeter. Both diaphragms are made of beryllium, which is both a very light metal and extremely rigid, properties that make its use optimal. The diaphragms are produced using a vapor-deposition technique developed by TAD. The profile of the tweeter dome was developed using what TAD calls the Harmonized Synthetic Diaphragm Optimum Method (HSDOM) of computer analysis. The result is a response that is truly pistonic within the audioband, and is claimed to extend to 100kHz. Because beryllium is very brittle, the CST drive-unit is protected by an integral wire-mesh grille, and is mounted within a silver-finished ring that smoothly continues the midrange cone's flare.
Frequencies below 250Hz are produced by an 8" woofer mounted below the CST unit on the CR1's matte-black front baffle. The woofer has what TAD calls a Tri-Laminate Composite Cone (TLCC). This features a central, foamed-acrylic core, with front and back woven coatings of an aramid material. Again, the goal was to produce a diaphragm that would be light and stiff, but with good internal damping. Unusually in these days of ubiquitous half-roll rubber surrounds, the woofer cone is terminated in a corrugated suspension that TAD claims offers high linearity. The voice-coil is 4" in diameter but only 12mm long, operating in a 22mm-long, magnet gap, which again confers excellent linearity over a wide range of cone excursion. TAD calls this an Optimized Field Geometry Magnet Structure (OFGMS). The woofer is reflex-loaded by a rectangular port at the base of the front baffle that is 9" wide by 1" high, including the flared profile at the port's sides, and is covered by a removable black mesh grille.
The crossover network features air-cored coils and film capacitors in the high-pass feed to the CST driver, and inductors with laminated steel cores in the low-pass woofer feed, to give high power handling and low saturation. Electrical connection is via two pairs of high-quality binding posts on an aluminum-alloy panel set into the enclosure's rear.
The Compact Reference's enclosure is made using what TAD calls Structurally Inert Laminated Enclosure Technology (SILENT). This has a strong internal framework formed by 0.9"-thick, CNC-machined birch plywood clad with high-frequency, hot-pressformed, laminated MDF panels. A 1.1"-thick aluminum base lowers the center of gravity and stabilizes the cabinet. The top of the cabinet and the gently curved side panels are veneered and finished in an attractive transparent coat. The matching, wooden, three-pillared stand has the same matte-black finish as the speaker's front baffle. Two small positioning pegs on the speaker's base fit into corresponding holes in the stand's top plate, and the stand is locked to the base of the speaker with an Allen-head bolt. The result is a visually unobtrusive yet attractively styled piece of furniture.
Andrew Jones helped me set up the Compact References in my room. And before you write to complain that this is special treatment, at this price level it should be mandatory for the dealer to set up the speakers in the customer's home. We moved the speakers back and forth and from side to side, using a CD that Andrew was familiar with, until he had gotten a balance between the midbass and upper bass that he felt was optimal. Only then did we screw the carpet-piercing cones into the bases of the stands. Though the low frequencies were extended, they were well controlled, meaning that the speakers could be placed a little closer to the sidewalls than with the Vivid B1s that had preceded them. The centers of the woofers ended up 75" from the wall behind them, 24" from the LPs and books that line their respective sidewalls, and 30" from the floor. This gave a rather wide-angle view into the soundstage, but that stage was stable, without any hole in the center.
Though the CR1 is ostensibly a stand-mounted design, it didn't lack low frequencies. The one-thirdoctave warble tones on Editor's Choice (CD, Stereophile STPH016-2) were reproduced with full weight down to the 32Hz band, but with a fast rolloff below. Listening to the half-stepspaced toneburst track from Editor's Choice with a stethoscope pressed against the enclosure revealed no resonances. The tonebursts "spoke" cleanly, with only a slight degree of blurring at the onset of each burst below 100Hzexcellent performance for a ported design. And again, the signal was reproduced with full weight to 32Hz.
I've been on a Bill Frisell jag since seeing the hyper-imaginative guitarist live at the Village Vanguard a few months ago. I somewhat belatedly picked up a copy of his 2001 Blues Dream album (CD, Nonesuch PRCD 300361), which has a Stygian double-bass ostinato underpinning the horn arrangement of "Ron Carter." The CR1 is not a minimonitor, of course, but the impact and weight of David Piltch's bass as reproduced by the TADs would have done a pair of big floorstanders proudit had me wondering where the subwoofer was!