Big Horn Reviews

WHAT HI-FI
TEMPTATION
MARCH
1999
Carfrae BigHorn Loudspeaker
We’ve reviewed some big speakers in our time, but these
behemoth boxes stand a staggering 2.2m tall. They’re the
brainchild of Jim Carfrae, whose fascination with horn
speakers led him to create a speaker radically different
from anything he’d seen, or heard, before.
The body of the horn is made from curved sections of
18mm birch ply, which can be finished with a choice
of real wood veneers. Everything else is made of solid
maple, a wood chosen for its tonal qualities as well
as its looks.
The extraordinary look of the CarfraeHorns is dictated
by the use of a ‘tractrix contour’ - a shape derived from
mathematics to give the soundwaves a clear path through
the hom. The drive units are Lowther DX4s (costing
£6OO each), mounted directly to a 40mm-thick tube of
solid hardwood, while sensitivity is a high 108dB/W/m.
Hooked up to a Vardis S15 amplifier fed by a Michell Orbe
tumtahle and DPA Renaissance Pulse Array CD player,
the detail these speakers produce is
breathtakin. Listen to a selection
of Keb Mo tracks and every pluck
of guitar string or snap of a drum
is conveyed with lifelike accuracy.
Voices are handled particularly well,
kd lang’s solo vocal on Don‘t Smoke
in Bed from her Drag album sounding pin-sharp and having tremendous
presence in the centre of what is a
wonderfully evocative soundstage.
The CarfraeHorns won’t suit all,
and they need a very large room to
accommodate them. But for sheer
delicacy, scale and intimacy they’re a
rare treat indeed.
S
W
E
VI
RE
Carfrae Loudspeakers
Ashleigh, Kingsbridge Hill, Totnes, Devon. TQ9 5SZ United Kingdom
E-mail: [email protected]
(
01803 868461
Web: www.carfrae.com
Fax
01803 868461
Anyone who visited the Excelsior
Hotel exhibits at The Hi-Fi Show
last September will remember
seeing a large, rather alienlooking speaker, presiding over the
entrance adjacent to the TAG McLaren
stand. This £18,000 construction is
the work of one Jim Carfrae, designer
and builder of horn speakers, and more
specifically those based on the Tractrix flare
contour. On a recent visit to the home of
Carfrae, I had an opportunity to see and hear
these remarkable horns in action.
Based in rural Devon, a few miles
outside Totnes and within trekking distance
of Dartmoor, a pair of these magnificent
horns were set up in an airy listening room
in the converted farmhouse from where
Carfrae works. Jim has devoted much time
and research into developing these speakers
into a commercial product
The main carcass of the loudspeaker
is made by a John Makepeace trained
cabinetmaker from continuous sections
of 18mm birch laminate ply, veneered to
customer specifications. By hand-building
this cabinet using a vacuum forming process,
the unique curve comes into shape which
avoids both straight lines and parallel
surfaces, and ensures no one section is
straight. This helps prevent the formation of
standing waves..
The Carfrae Horn was designed with
the help of Jim’s brother, an engineer who
wrote a software program to calculate the
course of the horn What differentiates this
horn’s profile from most designs is the
adherence to the ideal without any nasty
sharp bends, unavoidable when folding the
horn into a more compact box. This horn
deviates, it is claimed, by
no more than a millimetre
along its tract. The current
incarnation is designed
for the Lowther DX4
driver, a twin-coned driver
with lightweight paper diaphragm
and Neodymium magnet. This is held
rigidly in a 40mm thick wooden cylinder,
hewn from maple, with the rearward radiation
directed through the 3.34m Tractrix chamber.
But before the start of the horn proper, the
driver chamber acts as a low-pass filter,
screening frequencies above the upper cutoff of 200Hz- chosen as its wavelength is
an odd multiple of the horn length, avoiding
cancellation effects
Listening soon showed that the sounds
the system could make were an exercise
in naturalness, a step closer to the original
sound, as one well-quoted pundit would say.
In the sweet spot, some ten feet or so from
the horns (themselves backed into corners to
augment bass delivery), there was a tangible
presence in the room, excellent if not totally
3D imagery, and a stunning sense of detail.
The vinyl front-end comprehensively bettered
the CD rival-not through any particular fault
in the digital equipment, which I have heard
giving believable results before- but maybe
because of the purist ethos in the analogue
front end.
With CDs, the horns proved
they could play at high volumes
with little sense of constriction
or ‘cuppy’ coloration, handling
dynamics as only a good horn
can. Low-level detail was
astonishing, giving a great sense
of atmosphere, especially with
live acoustic music. A jazz
quartet piece featuring two
double basses showed not only
the subtly different timbres of
the instruments but also the
techniques of the respective
players-all with palpable
imaging. And talking of
bass, this was not that
shy, despite the design’s
inherent sudden rolloff
below a specific
frequency.
The
quoted
literature
notes a response of
32Hz-22kHz (no dB
roll-offs given), and
the speaker was heard
to go deep despite
the DX4 not being
optimised for the
horn at the time of
my visit. This has,
I am informed,
now been corrected for the
better.
From the initial concept,
it has taken two years to arrive
at the horn made today. Now,
the virtually no-compromise
design of the original horn is
about to be joined by a smaller
and cheaper version, known
affectionately as the ‘Little Big
Horn’ and scheduled to debut at
the Frankfurt High-End Show.
Jim hopes to sell this half-scale
version (which may yet feature
an auxiliary bass driver to
supplement
the
lower
frequencies) for under £5000.
Until then there is this amazing
transducer to dream over, or to
save the pennies for.