KEF Audio Uni-Q - Manual (Page 4)

A lightweight neodymium magnet ‘pot’ and
relatively small cone movements allow the
lower midrange driver in the Model 207 to be
fitted with KEF’s short coil/long gap motor
system. Although this has an inherently linear
flux profile anyway, the design incorporates a
single aluminium Faraday ring around the pole
to eliminate any residual distortion.The
configuration also allows the diaphragm to
be thinner and lighter for increased sensitivity,
with a phase plug shaped to optimise
smooth response.
In the new bass drivers, KEF’s ultra-low
distortion motor system dramatically reduces
low frequency distortions. After extensive
research using the latest magnetics simulation
software, the system incorporates twin
balanced Faraday rings above and below the
coil to maintain a perfectly symmetrical flux
profile (both in and out of the gap) that
minimises flux modulation.Together with the
use of an ‘undercut’ T-pole, this configuration
has the effect of reducing second harmonic
distortion by as much as 20dB (for 1W input),
and third harmonic distortion by 10dB.
An open chassis and vented poles minimise any
noise from air trapped internally, and each bass
driver radiates directly from its own subdivided
internal enclosure to avoid the standing wave
distortions that usually afflict tall cabinets.With
less damping required, you get more sensitivity
- and the result is the clearest, most open bass
you’ve ever heard.
Time aligned with the
main array and
mounted in its
own chrome-plated
steel pod, KEF’s new 19mm
titanium dome hypertweeter is
essentially a scaled down version of the new
Uni-Q ® tweeter, with the same low distortion
characteristics at ‘super audio’ frequencies.
With flat response to
50kHz and useful energy
up to 80kHz, this massively
extended performance
envelope delivers every last
sonic detail encoded in the
latest wideband formats like SACD, SACD
multi-channel and DVD Audio.What you
actually hear is simply a sweeter, more
natural sound with crystal clear highs.
Less distortion at lower frequencies
Hypertweeter™
HD (dB)
60
50
40
30
20
20 200 500
FREQUENCY (Hz)
10"LF unit: 2nd harmonic HD (dB)
60
50
40
30
20
20 200 500
FREQUENCY (Hz)
10"LF unit: 3rd harmonic