amplifier to speaker connections
All connections should be made
with the amplifier switched OFF.
Ensure the integrity of all
connections prior to switching the
amplifier ON.
KEF Blade speakers are fitted with
purpose designed silver-plated
Bi-wire/Bi-amp terminals which
will accept bare wire, spade or
4mm connectors.
Most good quality speaker cables
have some indication, such as
colour coding or ‘ribbing’ on the
insulating material, indicating which
conductor is ‘+’ or positive.
Connection to the speakers can
then be made as follows:
Bare wire connections are the
simplest to achieve and involve
stripping 12.5mm (0.5in.) of
insulation to expose the speaker
wire core. (You should twist
together, using clean fingers, the
ends of each multi-stranded core
prior to the next stage to ensure
a good signal contact). Having
unscrewed the lower terminal
cap, push the wire through the
exposed hole in the terminal
body and screw the cap
down tightly.
Make sure that no stray strands
come into contact with the
opposite terminal; this could
cause a short circuit between
the terminals and may damage
your amplifier.
Be aware that a higher quality run
of cable will always give a more
rewarding presentation than
multiple runs of an inferior cable.
Installation and operation
The left channel amplifier output
terminal marked ‘+’ or coloured
RED connects to the left speaker
terminal marked ‘+’. The left
channel amplifier output terminal
marked ‘-’ or coloured BLACK
connects to the left speaker
terminal marked ‘-’. Similarly, these
instructions should be followed for
making connections between the
right channel amplifier output and
the right speaker. Correct polarity,
or phase, is vital to the proper
operation of the system.
If the connections are not made
correctly the sound will
deteriorate giving poor bass
output and a diffuse presentation
of the soundstage.
amplifier requirements
and power handling
In KEF literature and in the
specification table within these
instructions are listed a range of
amplifier power outputs to match
your Blade speakers. Conditions of
use (room size, type of
programme, preferred listening
level) and the nature of the
speaker/amplifier interface vary so
widely that it is not possible to lay
down hard and fast rules about
amplifiers and the speakers
they drive.
KEF speakers are built to rigorous
standards of quality and
consistency and the upper limits of
the amplifier requirements shown
are those which the speaker in
question should handle without
distress or damage when used
under normal domestic conditions.
Remember it is easier to damage
the speaker by using a small
amplifier driven into distortion by
too much volume, possibly with
bass and treble boost, than by
using a larger amplifier which has
power in reserve. If in doubt,
ask the advice of your retailer
or consultant.
Installation and operation
If higher than specified amplifier
powers are used, great care should
be taken to avoid abnormal
conditions such as switch-on
surges or gross distortion, either
of the amplifier or the speaker,
resulting in power peaks greatly in
excess of the ratings specified.
Care should be taken as the
possibility still exists under certain
conditions (such as excessive bass
or treble boost caused by tone
and/or loudness controls, graphic
equalisers, etc.) that the speakers
can be overloaded and damaged.
The lower limits of amplifier
power are those necessary to give
a reasonable sound pressure level
under domestic conditions.
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