McIntosh MAC 4100, Руководство пользователя, Страница: 14 / 27

same, regardless of the position of the volume con-
trol. This contour is accurately modelled after the
family of "Equal Loudness" curves identified by
Fletcher and Munson.
The loudness circuitry is completely independent
of the volume control. Therefore, any desired
amount of compensation can be introduced
regardless of volume control position.
VOLUME CONTROL
The VOLUME con-
trol is a precision step
control manufactured
for Mclntosh Labora-
tory. It has 32 steps
with a 70 dB range,
plus volume off. Left
and right channel
tracking are within
1 dB. This extreme accuracy is obtained through
special electronically controlled resistance element
trimming. Since the switch commutator touches on-
ly contact pads and not the precision resistor
elements, tracking accuracy is permanently main-
tained and is noise free.
HEADPHONE JACKS
The front panel HEADPHONE jacks have been
designed to feed low impedance dynamic head-
phones. Electrostatic headphones generally require
higher power than dynamic headphones. They must
be connected to the speaker push connectors on the
rear panel.
Plug headphones into the front panel HEAD-
PHONE jack. Adjust the front panel VOLUME control
for comfortable headphone listening.
Signal to the headphone jacks is not affected by
the SPEAKER switches.
Front Panel indicators
The MAC 4100 has three dial scales:
1. AM - marked 550 to 1600 kHz
2. FM - marked 88 to 108 MHz
3. Logging Scale - 0-100
As the tuning knob is turned, the tuning indicator
moves across the dial. To make tuning easier only
the portion of the indicator directly behind the ap-
propriate dial scale is lighted. On FM, the upper por-
tion of the indicator is lighted. On AM, the lower por-
tion is lighted.
The logging scale can be used to accurately
retune any station. You may find it easier to keep a
record of your favorite stations by use of the logging
scale.
FM TUNING METER
An FM station is correctly
tuned when the meter needle is
in the black area of the FM tun-
ing meter and the AFL in-
dicator light is lighted.
SIGNAL STRENGTH METER
When tuning either an FM or AM signal the signal
strength meter indicates the strength of the signal
as received from the antenna. The higher the indica-
tion the stronger the signal.
AMPLIFIER POWER
OUTPUT INDICATORS
The amplifier POWER output in-
dicators are to the left of the tuning
dial. There are two vertical columns
of seven yellow Light Emitting Diode
[LED] indicators - the left column for
the left channel and right column for-
the right channel.
As power to the loudspeakers is increased, more
LEDs are turned on, vertically, indicating the in-
crease. Each row is independent of the other. The
LEDs provide constant and instant information on
the amount of power being fed to your speakers.
POWER GUARD
POWER GUARD assures that the amplifier can not
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