The D7
The D7 benefits from all the things Spencer Hughes couldn’t
dream of. Computer-aided design. Computeraided manufacturing (CAM) with
computer-numerical control (CNC) machines. The ability to whip up and test
prototype drivers within hours rather than weeks or months. Automation. The D7
has a small footprint, as they say on the sales floor: 38" high (including
spikes) by a mere 7.5" wide by 12.5" deep. Each weighs 46 lbs. A
built-in platform ensures stability around dogs, cats, drunks. Each speaker has
a port in a recessed chamber under the speaker connectors. Spike ’em good.
(When the BC1 was invented, spikes had not yet been thought of.)
Top: The D7’s
three drive-units are made by Spendor: a Kevlar-composite-cone woofer, a
polymer-cone midrange unit, and a tweeter built on a stainless-steel faceplate.
The D7’s claimed sensitivity is 90dB/W/m. Its nominal
impedance is specified as 8 ohms, not dropping below 4.5 ohms. I preferred the
8 ohm taps on my Quicksilver Silver 88 tubed monoblocks—a superb combination
with the D7s, as was my solidstate Musical Fidelity M6PRX stereo power amp.
Preamp? None, of course. I used my Music First Baby Reference transformer
volume control. A trusty, vintage Denon DCD-1650AR CD player provided digital
output to my Musical Fidelity Tri-Vista DAC. The D7s did take some running in
to come on song, as the British like to say. Dynamics opened up as the midrange
and bass drivers limbered up. The bass extension improved over time, to the
point where it is now excellent. Indeed, the D7 is one of the finest
loudspeakers I have had in my listening room. I take back everything bad I’ve
written about floorstanding speakers: troublesome bass, poor integration of
drivers in the nearfield, etc.
Middle: The D7’s
complex crossover. Note the right-angle orientation of the inductors, to
minimize magnetic interaction.
Jay Rein, of Bluebird Music Limited, Spendor’s North
American distributor, delivered the Spendors and plopped them down in my
listening room, where I’d laid down tape to mark the positions of some other
speakers. Since then, I haven’t moved the D7s so much as an inch. They’re about
3' from the sidewalls, 4' from the front wall, and about 9' apart. My listening
chair is 6' from the speakers. I find it far easier to move my Throne (as
Marina calls it) than the speakers
The D7s gave me the kind of imaging and image specificity I
associate with small stand-mounted monitors. You know how Brits like to place
their speakers close to the front wall; the D7s seemed to want some distance—
at least 3'. They worked for me in the relative nearfield, toed in slightly. I
suspect that the D7 owner has considerable leeway in positioning them. If your
room is long and narrow, you might get away with placing them about 4' from the
front wall and very close to the sidewalls
Over the years, all sorts of materials have been tried for
woofer cones. Doped paper. Plastic recycled from old shampoo bottles. Hemp.
Aluminum (ouch). The D7’s 7" (180mm) mid/woofer has a cone of copolymer
(plastic); the 7" woofer—or “LF drive unit,” as Spendor calls it—has a
Kevlarcomposite cone. Kevlar is the stiff stuff used for everything from body
armor to bicycle tires to hunting trousers. The 7⁄8" (22mm) tweeter sports
a precision-woven polyamide dome, if that catches your fancy—it’s fabric, not
metal. I’m more interested in the way the tweeter is built into a damped
acoustical chamber, with the dome behind a protective plate of stainless steel.
A phase-correcting screen built into the plate is said to allow all parts of
the dome to act in a similar, linear fashion, and guards against the prying
digits of fool audiophiles. That’s the short of it. For more technical details,
see Spendor’s website, where you can mull such terms as linear pressure zone.
