Cantata - Gryphon Audio Designs

EQUIPMENT REVIEW
The Gryphon Cantata Loudspeaker
by Roy Gregory
Regardless of approach, there’s one great
imponderable in loudspeaker design.
Whether you’re working with sealed
boxes or ported enclosures, dipolar
panels or horn loading, sooner or later
your creation will find its way into a
room, and that room is the one thing
you have absolutely no control over,
particularly when it comes to low
frequency performance. Indeed, the
requirements of good mid-band
performance and decent bass extension
are so completely contradictory that
it’s remarkable that loudspeakers work
as well in the real world as they do.
This isn’t exactly news, and
accounts for the current fascination
with (increasingly successful)
sub-woofer design and the
(as yet musically unsuccessful)
DSP correction of low frequencies.
It’s a topic that PM touches on in his
column this month, musing on the
practicalities of adjustable porting
for loudspeakers. So far, each and every
solution to the issue of room interfacing,
be it the Alison wall-proximity designs,
the various applications of DSP ranging
from Meridian to Infinity and B&O,
or the direct/reflected sound of the
Bose 901, has thrown at least one
musical baby out with the bath-water.
Instead, careful positioning and a
fortunate match have generally delivered
the best results, with the serious
caveat that the lower you go the harder
it gets to get it right. And the bigger
the speaker gets as well.
Now Gryphon have taken a new
look at an old idea, addressing some
of the historical shortcomings along
the way. One of the great advantages
of active drive in a loudspeaker (or
sub-woofer) is that you compensate
electrically for the mechanical
limitations of your driver/cabinet
combination. It’s the reason that
Meridian have always managed to
extract such wide bandwidth from their
modestly dimensioned interactive
designs, from the M2 onwards. Various
people over the years have applied
electrical correction of low frequencies
to otherwise passive designs in an
effort to extend their low-frequency
performance. Bose did it with the 901,
but perhaps the best known incarnation
was KEF’s Qube equalisers, supplied
with the Reference Series 15 or so years
ago. These set a small, active bass
contour between the pre and power
amps, allowing the user to tailor the
low frequency extension. It’s an elegant
solution, but it’s also fraught
with problems,
the chief one
being the quality of
the electronics themselves.
The small boxes with their plastic
controls and wall-wart power supplies
were never going to go down well with
the audiophile audience. Given its
position in the system, any such
equaliser needs to be built as
well as the line-stage that’s
feeding it.
Well, with the
Cantata, Gryphon
have adopted exactly
the same overall approach,
except that they have engineered
their Q Controller to exactly the same
standards as their £8000 Sonata pre-amp.
As well as quality components, power
supply and casework, you get fully
balanced or single-ended connection,
and an array of front panel switches.
These allow you to mute or bypass the
unit as well as allowing you to select
one of three factory set bass contours.
There’s also a fourth switch to allow
a custom contour to be fitted, user
specified but built by Gryphon.
The purpose of the contours is to
match the low frequency characteristics
of the speaker to those of the room,
its roll-off to the room’s inherent low
frequency gain. They should extend the
system’s bass resonance point from
around 57Hz to around a rather healthy
35Hz, especially given the relatively slim
enclosure used. In so doing you alter
the speaker’s Q, hence the terminology:
what you’re actually trying to do is align
the Q of the speaker with the Q of the
room. There’s one other peculiarity with
the Cantata. The Q Controller is also
connected to each speaker by a thin,
grey cable attached with a multi-pin
plug. This carries 28V DC that is used
to bias the capacitors in the speaker’s
crossover, long held in some quarters
to offer significant sonic advantages.
The speaker itself is of relatively
modest dimensions, employing
two 125mm fibre-glass coned
bass-mid drivers, tilted and
symmetrically deposed
around the centrally located,
25mm doped fabric tweeter.
The drivers were developed
specifically for the Cantata in
conjunction with a well-known
Scandinavian manufacturer. All
feature substantial motor assemblies, the
tweeter’s being oil cooled. The cabinet
is massively braced, and considerable
care has gone into the contouring of
the baffle and driver surrounds. The
tweeter is mounted on the back of its
own carefully sculpted sub-baffle, itself
carved from a solid, 1Kg block of
aluminium. The crossover is hardwired
and constructed from hand-built
components. The air-cored inductors,
wound from copper foil and wax
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