McIntosh MX-117 Brochure

MX 117

AM-FM STEREO TUNER-PREAMPLIFIER

The MX 117 AM-FM Stereo Tuner-Preamplifier
concept is a total Mclntosh master control center
that allows you to select the matching Mclntosh

power amplifier for your individual requirements.
All needed inputs such as two record players, two
tape recorders and auxiliary can be accommodated,

along with the built-in AM-FM stereo tuner. The

advanced circuits and performance features of the

Mclntosh MX 117 make it an ideal and especially
convenient solution for the most discriminating
stereo listener.

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MX 117

The Mclntosh MX 117 is
shown in optional walnut veneer cabinet.

MX 117 F

1. FM AFL AUTOMATIC FREQUENCY LOCK

The Automatic Frequency Lock is a patented

Mclntosh circuit that activates when you tune to
the center frequency of an FM station. A varacter
diode fine tunes the tuner with a correction volt­age from the AFL circuit. When the center ON

-station vertical LED indicator lights, the AFL cir­cuit is in operation and the tuner stays locked to
the signal. There will be no drift from this accu-

rate tuning, insuring minimum distortion and best

overall FM performance.

2. ELECTRONIC FET ANALOG INPUT SWITCHING

All critical input switching is done electronically

using field effect transistor analog switches. The
front panel selector simply switches small
amounts of control DC voltage which turn the FET
analog switches on or off. Since the FET analog

switches are located near the input jacks, the

length of interconnecting leads is much shorter.
This design eliminates switching noise as well as
frequency loss caused by the longer signal leads

necessary in conventional circuits.

3. HEADPHONE—OUTPUT AMPLIFIER

The built-in headphone amplifier is capable of
driving a pair of dynamic headphones with less
than 0.02% harmonic distortion. Because of its
extremely low distortion and power capability, it

is also the main preamplifier output.

4. TRI-FREQUENCY PROGRAM EQUALIZER

Three separate controls allow the balance and re-

sponse of musical information to be adjusted
with far more flexibility than with conventional
tone controls. The center frequencies of the con­trols are 30 Hz, 750 Hz and 10 kHz. Plus and minus

12 dB of control is available. Use of the program
equalizer controls does not affect in the slightest
the low noise, low distortion performance of the

tuner-preamplifier. When the equalizer controls

are in their center detent or flat position, their ac-

tion is neutral and response of the tuner-pre-

amplifier is absolutely flat.

5. TRUE LOUDNESS

COMPENSATION

The MX 117 active circuit loudness control is con­tinuously variable with constant midrange gain
and operates independently of the volume con­trol. The loudness contour is accurately modeled
after the Fletcher Munson family of "Equal Loud-

ness" curves. Use of this control restores proper
perceived frequency response at even the softest
listening levels.

6. PRECISION TRACKING VOLUME CONTROL

The volume control manufactured for Mclntosh

Laboratory is a step attenuator which has track-

ing accuracy within 1 dB throughout its entire
range. Such extremely accurate matching is
achieved through electronically controlled trimm-

ing of the resistance material deposited on pairs
of miniature printed circuits. Tracking accuracy
and quiet performance are permanently maintain­ed. Use does not affect performance as in ordin­ary volume controls.