Specifications

THE McINTOSH C 27
STEREO PREAMPLIFIER
STATE-OF-THE-ART
PERFORMANCE WITH
FLEXIBILITY
PERFORMANCE LIMITS and RATINGS
FREQUENCY RESPONSE:
+ 0, -0.5 dB 20 Hz to 20,000 Hz.
DISTORTION:
Will not exceed 0.05% at rated output level, 20 Hz
to 20,000 Hz.
INPUT SENSITIVITY AND IMPEDANCE:
Auxiliary 1 and 2, Tuner, Tape 1 and 2: 250
millivolts at 100,000 ohms. Phono 1 and 2: 2
millivolts at 47,000 ohms and 100 pF.
HUM AND NOISE:
Auxiliary 1 and 2, Tuner, Tape 1 and 2: IHFA 90 dB;
unweighted 85 dB below rated output. Phono 1
and 2 IHFA 85 dB; unweighted 80 dB below 10
millivolts input.
OUTPUT LEVEL:
Main Output: 2.5 volts with rated input. Maximum
output is greater than 10 volts. Tape Output: 0.25
volts with rated input. Maximum output is greater
than 10 volts. Center Channel Output: (L + R) 2.5
volts with rated input.
SEMICONDUCTOR COMPLEMENT:
18 silicon-planar transistors, 4 silicon diodes, 5
light emitting diodes.
AC POWER OUTLETS:
1 unswitched (red), 4 switched (black).
POWER REQUIREMENT:
120 volts, 50/60 Hz, 15 watts.
FACILITIES AND FEATURES
BASS:
Separate 11 position rotary switches for each
channel. - 17 dB to + 16 dB at 20 Hz.
TREBLE:
Separate 11 position rotary switches for each
channel -20 dB to +20 dB at 20kHz.
LOUDNESS:
Flat response, or continuously variable loudness
equalization as volume level is reduced.
BALANCE:
Natural balance at center position, attenuation of
left or right channel by rotating control.
VOLUME:
Precision step attenuator for precision tracking at
all listening levels. Does not change stereo
balance as volume is changed.
INPUT:
5 positions—Auxiliary 1 and 2, Tuner, Phono 1 and 2.
MODE:
7 positions—Left channel only to both speakers.
Right channel only to both speakers, Stereo
Reverse, Stereo, Mono (L + R), L + R to Left
speaker only, and L + R to Right speaker only.
TAPE MONITOR:
Two pushbutton switches. Either of two tape
recorders may be monitored.
TAPE COPY SWITCH:
Two pushbutton switches. Either of two tape
recorders may be connected to copy from one to
the other in either direction.
LF FILTER (Rumble Filter):
Flat or roll-off 6 dB per octave below 50 Hz, down
12 dB at 20 Hz.
HF FILTER (Scratch Filter):
Flat or roll-off 6 dB per octave above 5kHz, down
12 dB at 20k Hz.
C 504 is a compact
state-of-the-art preamplifier.
PERFORMANCE LIMITS and RATINGS
C 504 is the same as the preamplifier section of
the MX 117 found on page 38.
MECHANICAL INFORMATION
SIZE:
Front panel measures 16 inches wide (40.6 cm) by
3 5/8 inches high (9.2 cm). Chassis measures 14
3/4 inches wide (37.5 cm) by 2 3/8 inches high (6.0
cm) by 14 1/2 inches deep (36.8 cm), including con-
nectors. Knob clearance required is 1 1/4 inches
(3.2 cm) in front of mounting panel.
FINISH:
Front panel is anodized gold and black with
special gold/teal nomenclature illumination.
Chassis is black.
MOUNTING:
Mclntosh developed professional PANLOC.
WEIGHT:
14 pounds (6.4 kg) net, 25 pounds (11. kg) in ship-
ping carton.
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