It is advisable to keep the series resistance of connecting cables as
low as possible by using reasonably heavy gauge cables. Our recom-
mendations are.—
Loudspeakers under 10 metres away from amplifier: use 16/0.2mm.
Loudspeakers over 10 metres away from amplifier: use 2 4 / 0 . 2 m m .
Phasing. The centre image and correct spread in stereophonic re-
production relies on "in phase" components of sound of equal ampli-
tude, and it is essential to check that your loudspeaker and other
items in the "reproducing chain" are correctly connected. If other
items in the chain, such as pick-up cartridge, etc., are correctly con-
nected, then the method of connection of the loudspeakers as outlined
above will be correct. However, there is a simple test w o r t h m a k i n g : —
Feed both channels of your system w i t h a monophonic source, e.g.
mono radio, a mono record, or a stereophonic source w i t h the function
selector of the control unit of your amplifier switched to "A + B",
"Left + Right", or " M O N O . " If phasing is correct, then, when listen-
ing from a central position between the loudspeakers, the sound should
appear to emanate from a relatively small area between the loudspeak-
ers. If the phasing is incorrect, the image will be broader and spread
across the area between the loudspeakers. (Commercial gramophone
records are available which illustrate this " p h a s i n g " procedure, should
there remain any difficulty or doubt.)
If phasing of any item is incorrect, reversal of any one item will correct
the fault.
Operation. At the rear of the 701 electrostatic unit will be found a
removable absorbent pad, the function of which is to reduce rear
radiation in locations where the loudspeaker is placed close to a wall
or corner. This pad provides a useful method of varying the distribution
pattern of the electrostatic unit above 500Hz. to suit both ambient
conditions and the user's personal preference in terms of the ratio of
direct to reflected sound. This absorbent pad can be readily w i t h d r a w n
w i t h the fingers from its recess in the rear of the electrostatic mount.
W i t h the rear pad w i t h d r a w n , greater ambience will be experienced—
depending on the reflective nature of the wall and furnishings behind
the loudspeaker — there will be a slight increase in sound level above
500Hz. with the electrostatic unit operating in this condition. If it is
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