Hybrids are supposed to be the best of two or more technologies, and we’ve seen the approach used for all manner of products. Solid-state-plus-valve electronics, moving-coil cartridges with ‘Decca’ architecture — I could go on and on. The most feverish of hi-fi’s Dr Frankensteins, though, have always been devoted to loudspeakers.
Name any type of tweeter and I can assure you that it’s been mated to a cone-type bass driver. The reasons are simple: planar tweeters (electrostatic, isodynamic etc) offer the speed, openness or transparency not generally available from cone or dome tweeters, while cone woofers offer greater damping, control, ‘snap, efficiency and domestic suitability than manageable panel-type bass units can deliver. This isn’t to suggest that cone bass drivers are superior to panel woofers, only that they’re usually more practical and cost-effective.
Ribbon/cone hybrids have been around for years, with the Germans producing variants in the way that the British pump out £99 per pair budget speakers. Among the most famous, though, is the Decca London enclosure, which used Stan Kelly’s ribbon, so there are British precedents. SD Acoustics, Alphason — this hybrid may be slightly off-the-wall, but it’s not uncommon. Tweaky, yes, but not all that rare.
Noble though the efforts of SD and the others may be, their products are fairly exclusive and less ‘commercial’ than is required for spreading the word beyond audiophile circles. Now it’s time for one of the majors to step in, and with a design to address the curses which keep ribbon technology from being truly affordable and domestically acceptable.
Celestion’s 3000 attempts to banish the problems of low sensitivity, death-defying impedances, low power handling, domestically aggravating siting requirements and a host of other concerns. Indeed, the Celestion 3000 is the most ‘complete’ new
product I’ve examined in years, with every single detail — right
down to the owner’s manual — dealt with in full before a single
unit left the factory. Aesthetics, fit and finish,
fine-tuning…nothing’s been left to chance.
The 3000 (and the 5000, which is identical except for cabinet
finish) employs a box-type enclosure measuring a mere
650x330x300mm (HWD). It’s substantial, assembled from high
density particle board and made rigid with figure-of-eight
internal bracing. The company also offers a sonically and
aesthetically ideal support for #159 per pair which stands 550mm
tall; I can’t imagine anyone not using this beautifully styled,
sand-and-lead-filled, spiked sculpture. The novelty of a ribbon
tweeter is highlighted by an aluminum casting which runs the
height of the speaker, at an angle and situated on the inner edge
of the baffle. As you’d expect; the speakers are supplied in
left-and-right-handed pairs. The 3000 is all black; for an extra
#100, you can purchase the 5000, identical except for walnut
The front surface is covered by a black grille cloth on a solid,
sculpted frame; it protects a 200mm polyolefine cone bass bass
driver, which operates up to 900Hz. The grille has been designed
to create a smooth surface on the outside edge of the ribbon’s
chassis, mirroring the inner, veneered surface, so the grilles
should be left in place at all times.
The back contains binding posts for single, bi-wire or bi-amping
connections, and they accept spaced banana plugs. For some
strange reason, Celestion fitted them in a row reading (from left
to right) treble minus, bass minus, bass plus, treble plus, so
you’ve got to interleave and spread the wires across the
connectors; I’d have preferred to see the connections grouped as
bass plus/minus and treble plus/minus, but this is a small
quibble. It simply meant paying attention to the wiring of the
spaced bananas I insist on using.
And now for the ribbon. This 500mm driver consists of a narrow
strip of 12 micron thick, corrugated aluminum foil suspended
between two rows of strontium ferrite bar magnets. Although it
looks like a clone of the Apogee tweeter, it differs in details.
For starters, the ribbon itself is pure aluminum without any
backing; the Apogee uses Kapton. At the top and bottom, the
Celestion ribbon is connected with a foam-damped ‘kink’ in the
ribbon to relieve strain. Where Apogee uses foam ‘knuckles’ to
support and centre the ribbon at various points, Celestion uses
stretched silicon rubber belts supported by small pillars on
either side of the ribbon. The other major difference relates to
the 3000’s non-dipole status.
There is no gap between the ribbon’s edges and the magnets, a
critically selected gap being required for use in dipole
installations. With the Celestion, the sound firing from the back
of the ribbon is reflected off of the surfaces in the speaker
cabinet, the ribbon actually being mounted to its own separate
enclosure within the 3000. This partially explains why the ribbon
is mounted at a 45 degree angle to the enclosure; the rear-firing
sound fires directly into absorptive foam and out of harm’s way.
The other reason for the 45 degree angle is to aid in positioning
and the creation of a line source which disperses sound in a
cylindrical manner. I mentioned before that the rigid grille is
to be left in place so as to create smooth surfaces on either
side of the ribbon. This fools the driver into reacting to the
cabinet as if it were a cylinder, the result being an enclosure
which has no edges to cause diffraction. In practice, it means
that the only requirements for siting concern the bass, because
‘toe-in’ requirements have been eliminated. Sayonara, hot seat.
These are, without doubt, the easiest speakers I’ve ever reviewed
as far as positioning is concerned, save for certain types where
the siting is fixed or quite specific (e.g. Bose 901s, some
Allisons). Celestion recommends that they stand approximately six
inches from the back wall, with the backs parallel to the wall.
Because of the dispersion characteristics of the ribbons, the
distance between the speakers is not critical. The further apart
you’re able to place them, the wider the sound stage they’ll
produce. I had to move them over 15 feet apart before I could
detect anything resembling a ‘hole in the middle’, from a
listening position 12 feet away. Naturally, you’ll augment the
bass if the speakers are too close to the side walls, but that’s
true of most loudspeakers. Where I differed from Celestion’s
preferred siting is in the distance from the back wall. I found
the bass just a bit too overpowering, so the ideal spot in my
room was 15in from the back wall.
Amplifier selection is another matter entirely, and I wasted a
whole week before I hit on the first of three magic combinations.
Arbitrary though it may be, I try to review speakers with the
kind of amplifiers which I think the consumer will use, as well
as with ‘reference’ amplifiers. The argument for the latter is
that only by hooking up a pair of, say, #99 Celestion 3s to a
#10,000 Rowland will I be able to assess the full potential of
the speaker. On the other hand, the reviews are only valid for
the readers if the speakers have been tried with likely
In the case of the 3000, I had to throw out all of the rules. I
started with what I thought would be a sensible choice for a
speaker/stand combination at this price point, the #1250
Counterpoint SA-12. (Also, I should add, a hybrid.) For 80
percent of the time, all was wonderful except for the handling of
torture tracks I use to test sibilance. These include recordings
which are ‘right on the edge’, such as Juice Newton’s ‘Break It
To Me Gently’ or Poco’s Head Over Heels. The 3000/SA12 pairing,
while stunning in most respects, simply fell to pieces. And it
was a textbook lesson in why you should always audition a
potential purchase with the system in which it will reside. The
Counterpoint — sweet and smooth with the Sonus Fabers — sounded
edgy with the Celestion 3000, the opposite of its general
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