Magenta TT10, Инструкции по настройке

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ADJUSTING THE MAGENTA TT10 TURNTABLE
BIAS COMPENSATION
When a disc is spinning and you place a small object on it, the object will
be swept off the disc by the
centrifugal force (CF). You can try this
yourself by placing a small object on the platter.
When a record is turning, and the needle tip is held in a spiral groove at
one end and the tonearm is fixed on the other end, a force will be
exercised on the arm and cartridge. This force has now become
a
centripetal force (CP) which will move the cartridge towards the spindle,
all caused by the fixation at the pivot of the arm. Now the arm can only
move in a radial way as it is held in position by the pivot.
The result is that there will be an increased pressure on the groove wall
which contains the sound of the left channel.
In order to neutralize this
force, and to give both groove walls equal pressure, it is necessary to
compensate this effect by applying a counteracting force at the other end
of the arm, passed the pivot (BA). The force to be applied is called side
thrust compensation or bias compensation. It is done by means of a
pending weight or a magnetic force.
A linear / parallel tracking arm does not need this correction
because the pivot continuously changes its position.
When adjusting the bias or side thrust (BA) precisely, use a test record
with a groove-less section. The right amount of side thrust compensation
(in relation to the downforce) will keep the cartridge from moving either
towards the spindle or towards the periphery of the LP record.
You may also play the tracks of a test record containing heavily
modulated signals for left and right, and listen carefully at what level of
bias compen down force the distortion is the least, or even
completely absent.