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With the internal jumpers removed,
the EQ curve will conform to a 1978
RIAA addendum for the inclusion of
a -3 dB rumble filter at 30 Hz.
With the internal jumpers installed,
the EQ curve will not include the –3
dB rumble filter at 30 Hz. This
setting is designed for use with
extremely high-quality turntables
where rumble is generally not a
concern.
5. Line A, Line B and Line C
input level adjustment
As supplied from the factory, all trim
pots within the PL-P are set to
represent 1.0 V sensitivity at 0 dB
on the modulometer. However,
adjustments can be made to
accommodate specific installation
requirements.
On the inside left of the PL-P case
is a printed circuit board which is
connected to the input connectors
of Line A, Line B and Line C.
Directly above each pair of
connectors are a pair of trim pots,
designed to be adjusted using the
supplied miniature blue jeweler’s
screwdriver.
There are three pairs of trim pots in
total.
Each pair of trim pots can be used
to adjust the level of its
corresponding input. With a
clockwise turn of the white
adjustment screw in the center of
the trim pot, the input level is
increased; with a counterclockwise,
the level is decreased.
This adjustment technique is used
to balance the levels to avoid
variations across Phono, Line A,
Line B and Line C.
Used in conjunction with the
modulometer, as described below,
the user can also maximize system
performance by selecting the
optimum operating range for each
input source and the PL-P.
Using the modulometer
Description
The PL-P is equipped with a highly
precise multiple-purpose Nagra
modulometer. It has 2 coaxial
pointers, the black representing the
Left Channel and the red
representing the Right Channel.
The face of the instrument is
graduated with 3 scales and can be
illuminated by 2 internal LEDs.
The modulometer is a precision
instrument with very special pointer
ballistics.
A modulometer is different from a
VU or a PPM meter. They share a
common purpose of indication, and
a brief description of each follows:
• Modulometer
The modulometer measures the
peak value of the signal,
irrespective of the form or the
level, and takes into
consideration the strongest
positive or negative value. It is
equipped with a memory, so that
with very brief signals, the
