Kef Cantor III Brochure 2

Page 1

KEF CANTOR III

Cantor [II is a compact 2-way
loudspeaker system incorporating a
passive bass radiator to extend low
frequency response. Constmction and
drive units complement resemble that
of Chorale 111 from which it is
derived. Styling is simple and
restrained with smart front baffle
graphics, matching contemporary
trends in decor for those who prefer to
listen with the grille removed.

Cantor HI is intended for those
applications which demand small
unobtrusive loudspeakers without
sacrifice of musical quality or
restriction of frequency range.

Optimisation of parameters in the
acoustic circuit comprising low
frequency driver, passive bass radiator
and enclosure extends useful bass
output below SOHZ. Frequency
response is nominally flat to 70Hz
when Cantor III stands clear of room
wallsi Placing the speakers against a
wall will extend the response fiat
down to 60Hz. Better stereo images
will always be perceived however,
when the loudspeaker is mounted on
stands clear of large flat surfaces. This
is because sound diffracted no the rear
of the loudspeakers helps to create a
more natural, airy effect and an
impression of depth due to images
formed behind the loudspeakers,
unconfused by reflections from a walli

Its efficiency is medium to high at
87dB/W/m and it will safely handle
power from a 60W amplifier without
distortion or damage under audiophile
(see over) operating conditions The
optimum balance of performance, size
and power requirement proves once
again the importance of KEFs
engineering approach to loudspeaker
design and manufacture.

Cabinet work is finished in top quality
simulated walnut with brown textile
grille,

See overleaf for full technical
description and performance data,

Digital Recordings

Cantor III is perfectly suitable for
reproducing compact disc and other
types of digital recording with full
dynamic range.

KEF

Page 2

KEF CANTOR III

Cantor III is a two-way, three unic
system whose driven bass/mid range
unit is of 160mm nominal diameter.
The specially contoured fibre cone is
plastics coated to damp resonances and
is fitted with a convex PVC Roll
surround and a two layer 25mm Voice
coil.

In the Cantor III systems a 200mm
passive radiator is used to extend the
bass smoothly with a low distortion.

Compact reflex systems suffer from
nonrlinearities due to air turbulence in
the port which must of necessity be
very small in diameter, and to extend
bass response significantly in a sealed
box results in a loss of efficiency. The
use ofa passive radiator in a compact
system compromises neither distortion
nor efficiency. KEFs total system
design philosophy ensures that all
such parameters are optimised within
the design brief for the system
concerned.

The high frequency unit is of 30mm
nominal diameter. An impregnated
textile dome is driven by a two layer
coil 25mm in diameter wound on a
high temperature resistant former
using resin based adhesives.
Ferrofluid injected into the air gap
cools the voicercoil ensuring smooth
high frequency response and reliability
in service. Fluid cooling helps
minimise compression effects caused
by coil heating which result in
variations in high frequency response
at high volume levels.

The cabinet. constructed from high
density chipboard. provides bass
loading with 17 litres of air in
combination with a passive radiator.
Drive unit and cabinet parameters are
carefully matched to optimise low,
frequency performance. with panel
dimensions calculated to minimise
resonant modes leading to unwanted
colouration. Its exterior is finished in
high quality PVC foil with a knitted
textile grille 7 available in simulated
walnut or black ash.

S PECIFICATION

Frequency range:

TYPE SP 3029
58Hz to 20kHZ j: 3dB at 2m on reference axis (rlOdB at 43H: and 30kHz)

Within 2dB of response on reference axis
up to ZOkI-Iz for i 5" vertically
up to leHz for i 20 horizontally

Directional
characteristics:

Maximum output: 107dB spl on programme peaks under typical listening conditions

Characteristic
sensitivity level:

87dB spl at Im on reference axis for pink noise input of IW

Distortion: Measured at Im on reference axis at mean spl of 90dB, anechoic
conditions

Second harmonic:

less than I% from 90Hz to 20kI-Iz

Third harmonic:

less than 1% from 40Hz to ZOkI-Iz

Mechanical reflex

Enclosure type:

Internal volume: 17 litres

8 ohms
normal 80W, audiophile 100W

Nominal impedance:

Maximum amplifier
power:
(see explanatory note*)

Minimum amplifier normal low

power:

Weight: 6.8kg

Dimensions 502(h) >< 247(w) >< 212(d)mm
*AmpIi/ier Power

The maximum power input that can be applied safely depends on the type of programme and conditions
of use.
Normal use: programme with limited dynamic range, e.g. VHF transmissions, pro-recorded tape
cassettes. compressed pop records, etc.
Conditions of use include loud listening levels with power amplifier often driven into
clipping and tone controls or equaliser used to significantly boost low and high frequencies.
Audiophile reproduction of wide dynamic range recordings. e.g. direct Cut discs. compact discs and
use: digital tapes.
Conditions of use include flat replay characteristics with only occasional overloading of
power amplifier.

tolerance axis

\m 2m am

384

This sketch indicate: the limit: ofrhe listening window, in the
vertical plane, within which optimum tonal balance and
rtereophonic effects will be perceived.

For best result: the reference axis should be directed towards the listeners. It is therefore preferable to
raise the loudspeaker above thefluor. KEF stand ULS 40 is suitablefor this purpose.

KEF reserves the right to incorporate developments and amend the specifications without prior
notice, in line with continuous research and development.

Distribution in the USA by:

Intratec

PO Box 17414

Dulles International Airport
Washington, DC 20041 USA
Telephone: (703) 435 9100

KEF products are manufactured in
England and distributed in the
United Kingdom by:

KEF Electronics Ltd

Tovil

Maidstone

Kent ME15 6QP England
Telephone: Maidstone (0622) 672261
Telex: 96140

PRINTED lN ENGLAND Part No. PL 464 EN01