Specifications

Electronic Laboratories'
THE MCINTOSH MX 117
AM/FM TUNER-PREAMPLIFIER
MANUFACTURER'S PUBLISHED SPECIFICATIONS:
FM Tuner Section:
Usable Sensitivity: 1 1 .2 dBf (2.0 uV/300 ohms) 50
dB Quieting Sensitivity: 19.1 dBf, mono; 39.5 dBf,
stereo. Signal-to-Noise Ratio: 70 dB minimum, both
mono and stereo. Harmonic Distortion: 0.18%
mono, 0.38% stereo, maximum. Alternate Channel
Selectivity: 78 dB minimum. Image Rejection: 100
dB minimum. Stereo Separation: 45 dB minimum at
1 kHz.
AM Tuner Section:
Sensitivity: 75 uV (external antenna) Signal-to-Noise
Ratio: 45 dB min IHF or 55 dB @ 100% modulation.
Adjacent Channel Sensitivity: 30 dB Minimum. Im-
age Rejection: 65 dB minimum from 540 kHz to
1600 kHz. Frequency Response: +0, —6 dB, from
20 Hz to 3500 Hz.
Preamplifier Section:
Frequency Response: +0, -0.5 dB, 20 Hz to 20
kHz. Rated Outputs: Main: 2.5 V; Line: 1.25 V;
Headphone: 750 mV; Tape: 250 mV. Distortion:
0.02% max. @ 2.5 V output from 20 Hz to 20 kHz.
Input Sensitivity for 2.5 V at Main Out: (Phono) 2.2
mV; (High Level) 250 mV. Signal-to-Noise: (Phono,
re: 10 mV in) 90 dB "A" wt'd, 80 dB unwt'd. (High
Level, re: 250 mV in): 100 dB wt'd; 90 dB unwt'd.
Input Impedance: (Phono 1 & 2): 47 K ohm & 50 pF.
High Level: 47 K ohm. Output Impedance: (Main):
Less than 100 ohms; (Line): 600 ohms; (Phone): 8
ohms; (Tape): Less than 200 ohms. Equalizer Con-
trol Response: ± 1 2 dB at 30 Hz, 750 Hz and 10
kHz.
GENERAL SPECIFICATIONS:
Dimensions: 16" wide x 5-7/16" high (panel).
Chassis: 13" deep. Knob clearance in front of panel:
1 ¼ ". Net Weight: 24 Ibs.
Mclntosh Laboratory Inc. remains one of the few
companies that continues to offer a high fidelity
component which incorporates both FM/AM tuner
circuitry and preamplifier-control circuits. It strikes
us that for those audio enthusiasts who do want to
include radio (and particularly high-fidelity stereo FM
radio) as a program source in their audio systems,
this combination, on a single chassis, makes a great
deal of sense; so much so, in fact, that we have al-
ways wondered why other manufacturers have not
offered this type of component in greater numbers.
After all, it permits the user to choose any power am-
plifier he or she requires, allows for the incorporation
of two turntables as well as two tape decks, offers
the versatility of a separate preamp-control unit
while at the same time incorporating a top-perform-
ing stereo FM/AM tuner.
Front Panel Layout
The MX 1 1 7 has the unmistakable Mclntosh front
panel look, with its anodized gold and black finish,
its gold/teal illuminated nomenclature and its exclu-
sive PANLOC mounting system which has become a
tradition of Mac equipment. A large, well-illuminated
cut-out area of the panel contains the calibrated AM
and FM dial scales, and evenly spaced "logging
scale" (calibrated linearly in 0.1 increments from 0
to 10), seven small indicator lights (which denote
program source selected as well as selection of in-
terstation muting during FM listening) and a four-
teen-LED solid-state tuning indicator system, con-
sisting of ten small dots arranged in a vertical row, a
small bar which illuminates to denote stereo signal
reception and three bars which tell you whether you
are tuned above, below, or precisely "on center"
frequency when listening to FM.
A conventional, flywheel-coupled tuning knob is
positioned to the right of the dial area. All remaining
front panel controls are neatly arranged along the
lower section of the panel. These include a six-posi-
tion, program source selector switch at the lower left
(AUX, AM, FM, MUTE {FM}, PH{ono}1 and
PH{ono} 2), three tone controls to the right of center
(Mclntosh prefers to call them equalizer controls,
since they do divide the audio spectrum into three
parts, as opposed to simple bass and treble tone
controls which usually control wider swaths of fre-
quencies), a dual-concentric balance and loudness
control and a master volume control at the lower
right. Six push-button switches plus a stereo head-
phone jack are located to the left of center of the
panel. A light-colored button serves as the power
on/off switch while the contrasting dark-shaded but-
tons handle such functions as TAPE 1 or TAPE 2
monitoring, Tape Copying from either connected
tape deck to another, and stereo/mono selection.
The loudness control arrangement found on the MX
1 1 7 is different from any that we have previously
encountered and we shall have more to say about its
action presently.
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PRODUCT
ANALYSIS
Fig. 1 —Front panel view of
Mclntosh MX 1 1 7 Tuner-Preamplifier