The earliest
high-fidelity components were designed during the vacuum-tube era, and
generally followed broadcasting practice in separating tuner, power amplifier,
preamplifier and power supply, each circuit section on its own chassis.
The
characteristics of transistors, primarily their small size, cool operation and
indefinitive service life, permit the consoloidation of all of the electronic
circuitry needed in a high-fidelity system into one component, the receiver.
The AR
silicon solid state FM receiver is an integrated stereo FM tuner, stereo
preamplifier and power amplifier, mounted on one chassis. FET front end with 4-section capacitor,
multisection crystal IF filter, IC IF amplifiers, and 2µV sensitivity insure
superb FM reception.
The AR
receiver was under development for some time. When the amplifier section was
completed, several years ago, it was offered to the public as a separate
component. High Fidelity, citing test
reports from CBS laboratories, stated, "It is, in our view, an unqualified
success, a truly excellent and unimpeachable amplifier … (at 20% more than its
rated power) it either met or exceeded it specifications … the IM distortion
characterisctics must be counted as the best we've ever seen …" Stereo
Review called the amplifier's power "staggering", and added, "it
ranks among the very best available."
Circuit
Characteristics
(FM) FET
front end with 4-section variable capacitor;
Multisection
crystal IF filter;
IC
(integrated circuit) IF amplifiers;
Automatic
interstation noise suppression with defeat switch for very weak stations;
Automatic
mono/stereo FM switching with stereo indicator light;
Low-distortion
shunt multiplex detector;
Tuning
meter.
(Amplifier)
DC driver clamping for clean overload recovery;
Idling power
supply eliminates turn-on transient noises;
Bass and
treble separately controlled for each channel;
Differential
loudness compensation curves in bass control circuit;
Special null
circuit permits exact balancing of stereo source material;
Stable under
short-circuit of output terminals;
Line fuse,
speaker fuse and self-resetting circuit breakers for full protection.
The AR
receiver is guaranteed for 2 years from date of purchase.
The receiver
has now been completed by the addition of the circuitry required for stereo FM
broadcast reception which is in every respect the counterpart of the
performance of the amplifier. The receiver circuit is all-silicon solid state;
the most rigorous manufacturing and inspection techniques we know are used in
its assembly. The receiver is guaranteed for 2 years
While no
compromise is made with optimum performance, the AR receiver is lower inprice
than might be expected. This is because of the rational approach taken in its
design. The AR Receiver is as sensitive, precise and powerful a unit as is ever
likely to be needed in the home. In addition, it is one of the simplest to
operate; as in the best of professional equipment, control functions have been
limited to those which are actually needed.
Applicable
IHF test standards are used for the following guaranteed performance
specifications.
Specifications
Switched
Input Circuits: magnetic Phono; Tape
Playback; Extra high-level input pair
("Special")
Outputs: tape record;
4 - 16 Ω speakers; headphone jack on front panel; output to amplifier for center-channel or
mono extension speakers.
FM Section
Sensitivity: 2,0 microvolts or better (hush control
"off").
Signal-to-Noise
Ratio: 65 dB ASA "C" weighting
(flat)
Harmonic and
IM Distortion (Mono or stereo): less
than 0,5%
Frequency
Response: 20 to 15,000 Hz ±1 dB (mono or stereo)
Capture
ratio: 2 dB or less
Separation: 35 dB minimum at 50 Hz; 40 dB minimum at 400
Hz; 30 dB minimum at 10,000 Hz
Control
Amplifier Section
Power Output
(measured with both channels driven):
60
watts per channel RMS at 4 Ω
50
watts per channel RMS at 8 Ω
30
watts per channel RMS at 16 Ω
Distortion
(at any level up to and including full rated power)
IM
Distortion (60 and 7,000 Hz, 4:1): less
than 0,25%
Harmonic
Distortion: less than 0,5% from 20 to
20,000 Hz
Power
Supply: 110 - 220 V 50/60 Hz
Dimensions
(W x H x D): 16-5/8" x 5-11/16 x
11-1/8"(without cover)
With
Optional wood cover: 17-1/4" x
6" x 11-1/8"
