What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





Monitor Audio MA-201 loudspeakers

 Monitor Audio MA 201
Introducing - the one of two new models in the system 200 series are designed with precision tooling using unique materials for drive unit chassis and front baffle mounting. Micafilled polypropylene drive unit baffle is tongue and grooved resulting in rigid and non-resonant cabinet enclosures.

Model MA-201
is a compact speaker designed for stand or bookshelf mounting. two drive units are employed
a 165 mm paper cone bass driver and a Gold metal dome tweeter - in a rigid enclosure constrcted
from high-density particle board. Reflex loading is provided for the bass driver. Drive unit integration is performed by a first-order electrical network using high quality components.
Facilities are provided for bi-wiring.

Monitor Audio MA-202 loudspeakers

 Model MA-202
is a floor standing loudspeaker with an integral plinth and provision for floor spikes. Two drive units
are employed - a 165 mm paper cone bass driver and a Gold metal dome tweeter - in a rigid and well
braced enclosure constructed from 18 mm particle board. Reflex loading is provided for the bass driver.
Drive unit integration is performed by a first order electrical crossover network using high quality components.
Facilities are provided fpr bi-wiring

Fisher MT-6330 turntable

Linear Motor Direct Drive Turntable
Fisher's model MT-6330 "Studio Standard" semi-automatic direct-drive turntable makes use a linear drive in which the platter is actually the rotor of the motor. The company claims that this 120-pole linear drive design virtually eliminates "cogging action" and greatly reduces rumble. The unit offers convenient front-panel operation, variable calibrated anti-skate control, stylus pressure adjustment, strobe light and speed controls, viscous damped cueing, automatic tone arm return and shut-off, and a 2,2 pound cast aluminum platter.
Tracking force adjustment is by means of a calibrated counterweight.
Strobo Light
Automatic functions:  Tone arm return at end of record
Auto Functions: Stop, Reject
Manual Functions: Start, Stop

Specifications
Motor:  120-pole Linear AC Servo
Drive System:  Direct-drive
Wow and Flutter (WRMS):  0,035%
Rumble (DIN 45539B):  -70 dB
Speed Variation:  ±0,5%
Speed Control Range:  ±3%
Tracking Force Range:  0,6 - 3,5 grams
Platter Diameter:  314 mm
Platter Weight:  1,0 kg
Record Speeds:  33 and 45 rpm
Tone Arm
Resonance:  less than10 Hz
Balance Adjustment:  Counterweight
Effective Length:  222 mm
Shape:  S-form
Bearing Type
Horizontal:  Thrust
Friction Sensitivity:  0,18 gram
Vertical: Pivot
Friction Sensitivity:  0,22 gram
Max. Tracking Error:  ±1,8°
Anti-Skate Control:  Calibrated adjustable
Cueing:  Viscous Damped
Cartridge Supplied:  Stereo magnetic (MG-35V)
Power Requirements:  AC 110/120 V 50/60 Hz
Dimensions (W x H x D):  440 x 380 x 138 mm
Weight:  5,2 kg

Mitsubishi MS-40 loudspeakers

Mitsubishi Audio's MS-40 floor-standing loudspeaker system is a new top-of-the-line model that utilizes light and extremely rigid aluminum honeycomb in the woofer; the honeycomb is sandwiched between layers of glass fiber reinforced plastic to produce powerful bass response with excellent definition and clarity, according to the company. Ferro-nickel rings inn the woofer and midrange reduce distortion to a tenth of that in conventional designs. It's claimed, and a gain of 20 dB can be observed. The dome tweeter is nested in a cone-like recess to give a crisp, clear edge to transients and unusual smoothness to the highest frequencies.
The tweeter's edge material is of butyl rubber, which also permeates the foamed polystyrene that fills the cavity behind the hybrid dome tweeter. The tweeter also incorporates a drive magnet with very high flux density. A very sharp slope of 18 dB per octave for the high-pass filter between midrange and tweeter was selected as optimum. Inductors are dipped in special varnish to modify impedance characteristics of the crossover elements, capacitors with very low loss factors are used, and resistors are of special silicon-dipped material.
The speaker measures 15-3/8 inches in width, 15-5/16 inches in depth, and on its permanently attached base, it stands 34-5/8 inches high. If that's too tall for you, you can take the base off by loosening a set of holding screws.
The enclosure is finished in carefully matched walnut veneer, even on the front panel,, so you can play the speaker with the grille removed to show off its impressive array of drivers.
Its weight of 77 lbs, gives a clue too the solidity of the overall construction.

Specifications
Type:  Acoustic Suspension 3-way speaker system
Drivers:
Low Frequency:  12" high-compliance honeycomb woofer
Mid Frequency:  4" honeycomb midrange driver
High Frequency:  Hi-performance Hybrid-Dome tweeter


Sanyo Plus T55 tuner

Digital Tuner with Memory
Described as "the first radical departure in tuner design in four decades". Sanyo's Plus T55 tuner combines an electronically tuned front end and digitally programmable quartz crystal reference oscillator to provide "superb" audio performance. And thre's another unique benefit; it's impossible to mistune a station. As long as the station's frequency appears in the bright fluorescent digital display and the center tune indicator is lit, the receiver is perfectly tuned at the exact point of minimum noise and distortion. Plus T55 has a passive four-pole LC filter that is double-tuned to reject not only the 19 kHz multiplex pilot tune, but also the 38 kHz multiplex subcarrier. Thus the high frequency subcarrier cannot interact with the bias frequency of tape decks. The band/mode selector lets you choose AM or either of two FM modes; auto, with automatic switching to stereo  mode in the presence of a multiplex signal; and mono, which suppresses stereo information in all signals, allowing noisy stereo signals to be heard with improved quality.
 Specifications
FM Section
Frequency Range:  88- 108 MHz (100 kHz steps)
Usable Sensitivity (Mono):  1,8 µV (10,3 dBf)
Signal-to-Noise Ratio
Mono :  75 dB
Stereo :  70 dB
Total Harmonic Distortion (1 kHz)
Mono :  0,15% (Narrow);  0,09% (Wide)
Stereo :  0,2% (Narrow);  0,1% (Wide)
Frequency Response:  20 Hz - 15,000 Hz   +1 dB -2 dB
Alternate Channel Selectivity (at ±400 kHz)
80 dB (Narrow)
55 dB (Wide)
Capture Ratio
1,8 dB (Narrow)
1,2 dB (Wide)
Stereo Separation at 1khz
42 dB (Narrow)
48 dB (Wide)
AM Suppression:  60 dB
Image Rejection (at 98 MHz):  70 dB
Antenna Input:  300 Ω (balanced);  75 Ω (unbalanced)
AM Section
Frequency Range:  530 - 1,600 kHz (10 kHz steps)
Usable Sensitivity (at Ferrite Antenna):  300 µV/m
Signal-to-Noise Ratio (at 5 mV/m):  45 dB
Selectivity:  35 dB
Image Rejection (at 1,000 Hz):  50 dB
IF Rejection (at 1,000 kHz):  45 dB
Antenna:  ferrite bar antenna; External Antenna
General
Power Requirements:  AC 120 V 60 Hz;  200 V 50/60 Hz
Power Consumption:  9 W
Dimension (W x H x D):  440 x 270 x 44 mm (17-3/8 x 10-1/16 x 1-3/4 inch)
Weight:  5 kg (11 lbs)

Toshiba PC-X40 tape deck

Metal capable Stereo Cassette Deck
Toshiba's PC-X40 stereo cassette deck is a fully featured unit with an AS )All-Sendust) record playback head and ferrite erase head. It can play metal tapes. Also incorporated are: a digital IC controlled programmable multi-music quick sensor system able to program up to six different selections. There's also a skip / play function, two LED peak meters with changeable bar dot readout, auto-repeat functions, cue and review, and soft eject mechanism. Frequency Response is put at 20 Hz to 18,000 Hz ±3 dB at an input level of 20 dB. Wow and flutter is 0,05% WRMS. Signal-to-Noise ratio with metal tape is 72 dB with Dolby ON; 62 dB with Dolby OFF. Also with CrO₂ tape, 68 dB with Dolby ON, and 58 dB with Dolby OFF.

Specifications
Type: 2- head; 4-track; 2-channel stereo
Tape Speed:  4,75 cm/s
FF/Rewind Time C-60 :  80 sec
Input Sensitivity/Impedance:
Line :  70 mV/ 47 k Ω
Mic :  0,25 mV/600 Ω - 10 k Ω
Output Level/Impedance:
Line  Out :  0,5 V/47 k Ω
Phones:  1 mW/8 Ω
Power Source:  220 - 240 V 50/60 Hz
Power Consumption:  22 W
Dimensions (W x H x D):  420 x 116 x 278 mm
Weight:  5,3 kg

Shure M95 HE cartridge

Phono pickup
This is the next-to-the top-of the line Shure pick-up, which incorporates the same stylus as is used in the top-of-the-line model. Overall the sound quality is very good, with slightly hot highs, with user-replaceable stylus (which may also be used by those who now own the M95 pickup) .
A magnetic pickup with a "Hyper-elliptical" stylus and built-in "hinged" stylus guard. Recommended vertical tracking force is 3/4 to 1-1/2 grams and best rsults were attained in the 1-1/4 to 1-1/2 gram range.
The Frequency Response measured ±3 dB from 20 to 15,000 Hz, rising to +4,5 dB at 20,000 Hz. Overall channel balance was within 2 dB. The worst-case stereo separation was 23 dB at 1000 Hz; 20 dB at 15,000 Hz.
This pickup sounds a lot better than it measures.

Specifications
Frequency Response: 20 - 20,000 Hz
Output (at 1,000 Hz):  4,7 mV (at 5 cm/sec peak recorded velocity
Channel Separation:  25 dB at 1 kHz (minimum)
Channell Balance:  within 2 dB
Tip Tracking Force:  0,75 - 1,5 grams
Total Tone Arm Tracking Force (Destaticizer on record):  1,25 to 2,0 grams
Force Exerted by Destaticizer:  0,5 grams
Typical Trackability (in cm/sec. Peak recorded velocity)
400 Hz :  24 cm/sec
1,000 Hz :  33 cm/sec
10,000 :  19 cm/sec
Inductance:  700 millihenries
DC Resistance:  1550 Ω
Optimum Load:  47 Ω 9resistance in parallel with 200 to 300 picofarads capacitance per channel)
Net Weight:  6,4 grams

JVC SEA-80 equalizer

A new 10-band equalizer from JVC Corp can "tune your room" for audio reproduction of the highest quality. The equalizer utilizes a pink noise generator that simulates the response of the human ear; energy distribution is constant as the signal doubles between 100 Hz and 200 Hz ; for example. The SEA-80 is claimed to actually analyze a room's acoustic so that you can make exact compensations on each of the ten channels. A Fluorescent Spectrum Analyzer Display divides input into ten bands (corresponding to the center frequencies of the equalization controls) and displays the dB level of each on ten, bright fluorescent bars. An eleventh bar charts over-all volume. This visual graph of a room's acoustics ensures real equalization, says JVC. Each display bar is designed to rise rapidly and fall slowly to enhance the visual representation of what your ears actually hear. The display covers the frequency range from 32 Hz to 16,000 Hz over the range from "0" to 26 dB. The SEA-80's mode switch allows a graphic reading of either the left- or right channel signals alone, as well as both together. A memory feature allows holding an input indication for closer inspection. The unit is said to aid in control of high frequency signals when recording on cassette tapes.
 Specifications
Circuitry:
Buffer Amplifier:  FET-equiped, ICL-input, double-differential, equiphase-feedback circuit
S.E.A. Amplifier:  Double-differential input, DC configuration circuit
Semiconductor L Circuit:  Transistor-inductor circuit
Input Section Impedance:
SEA Input :  47 k Ω
Tape Mon. :  47 k Ω
Output Section Impedance:
SEA Output :  100 Ω
Tape Rec :  100 Ω
Rated Output:  2 V RMS (with all S.E.A. controls pos. At "0")
Total Harmonic Distortion:  0,003% (at 1 kHz rated output)
Intermodulation Distortion:  0,003%  (with all S.E.A. controls pos. At "0")
Gain:  0 dB with SEA switch Off; 0 dB with SEA switch On; -6 dB with SEA switch at -6 dB
Frequency Response :  10 - 100 kHz (+0 -2 dB)
Signal-to-Noise Ratio:  118 dB (at rated output IHF A-network short-circuit)
Control Section
SEA Center Frequencies:  31,5 Hz; 63 Hz; 125 Hz; 250 Hz; 500 Hz; 1 kHz; 2 kHz; 4 kHz; 8 kHz; 16 kHz
SEA Control Range:  ±12 dB
Pink Noise Section
Output ;  50 mV RMS
Microphone Amplifier
Matching Mic. Sensitivity:  more than -72 dB
Matching Mic. Impedance:  less than 1 k Ω
Mic. Attenuator;  -20 dB
Graphic Display Section
Mic. Switch at Off:  Indicates the level of signals leaving the SEA Output terminals
Mic. Switch at on or -20 dB:  Indicates the level of input signals to the microphone
Display Modes;  L; R; L + R; Off
Memory:  Normal display is restored a few seconds after the Memory switch is released to Off
General Section
Power Source:  AC 110 V / 120V / 220 V / 240 V (selectable) 50/60 Hz
Power Consumption:  26 W
Dimensions (W x H x D):  450 x 158 x 319
Weight:  8 kg

Sansui G-4700 receiver

Digital readouts and digital circuitry. Great specs. And the best-price / performance ratio in the business. All the right numbers. That's the new Sansui G-4700.
Double digital Design.
The front panel of the G-4700 has a bright electronic digital readout that shows the frequency of the station you've selected; and behind the front panel is one of the most advanced tuning systems in the world.
Sansui's patented Digitally Quartz-Locked Circuit uses a precise quartz crystal time base to keep your station locked in, even through many hours of listening or if you turn the receiver off and back on again.
Conventional quartz-controlled receivers use analog phase comparison circuits that can become inaccurate because of harmonic interference. Our system uses a new LSIC (Large Scale Integrated Circuit) digital processor that actually counts the vibrations of the quartz crystal to compare to the tuned frequency. The frequency is perfectly locked in the instant you find the station you want.
With the unique Digitally Quartz-Locked system, the G-4700 delivers high sensitivity , a better Signal-to-Noise ratio, and a better spurious rejection ratio.
DC Power Amplifier.
Power is ample for almost any speaker made, with 50 watts per channel, min. RMS, both channels driven into 8 ohms from 20 Hz to 20 kHz with no more than 0,05% Total Harmonic Distortion.
And the wide bandwidth DC power amp circuit responds quickly to transient music signals for the most accurate and pleasing music reproduction. What you hear is clean and sharp, just the way it was recorded.
Electronic LED Power Meters
Don'r worry if you present speakers can't handle 50 watts. The array of fast-actling LED's on the Sansui G-4700 lets you monitor and control the output level so you don't damage your speakers.
Electronic Tuning Meters.
Two fluorescent readouts help to zero-in on each station with accuracy and ease. Both the signal strength and center-tune indicators operate digitally for precise station selection, and the nearby LED verifies that the quartz circuit has locked in your station.
Superb Human Engineering.
A full complement of genuinely useful knobs, switches and jacks gives you complete control over what you hear and how you hear it.
Specifications:
Audio Section
Power Output (min. RMS, both channel driven, 20-20,000 Hz, no more than 0,05% T.H.D.):  50 watts per channel into 8 ohms
Load Impedance:  8 ohms
Total Harmonic Distortion :  less than 0,05% at or below rated min. RMS power output
Intermodulation Distortion (70 Hz : 7 kHz = 4 : 1 SMPTE method):  less than 0,05% at rated power output 
Frequency Response ( Overall from Tape/AUX, at 1 watt):  10 Hz to 70,000 Hz, +1,0 dB, -2,0 dB
RIAA Curve Deviation (Phono, 30 Hz - 15 kHz):  +0,5 dB, -0,5 dB
Damping Factor (1 kHz, both channel driven):  30 into 8 ohms
Input Sensitivity/ Impedance:
Phono 1 :  2,5 mV/47 k Ω (max. input capability :  200 mV at 1 kHz, less than 0,5% T.H.D.)
Aux, Tape  :  150 mV/47 k Ω
Output Level (at 1 kHz):  
Tape Rec (Pin jacks) :  150 mV
Hum and Noise (short-circuit, A-network):
Phono :  76 dB
Aux, Tape  :  95 dB
Channel Separation (at 1 kHz)
Phono :  50 dB
Aux, Tape :  50 dB
Controls
Bass :  ±10 dB at 50 Hz
Trebele :  ±10 dB at 10 kHz
Susbsonic Filter:  -3 dB at 18 kHz (6 dB/oct)
High Filter :  -3 dB at 3 kHz (6 dB/oct)
Loudness (Volume control -30 dB position):  9 dB at 50 Hz ;  6 db at 10 kHz
FM Tuner Section
Tuning Range:  88 to 108 MHz
Usable Sensitivity:
Mono  [IHF/DIN]:  10,8 dBf (1,9 µV) / 1,2 µV
Stereo IHF :  19 dBf
50 dB Quieting Sensitivity:
Mono :  15 dBf
Stereo :  38 dBf
Signal-to-Noise  Ratio (at 65 dBf):
Mono :  75 dB
Stereo :  70 dB
Distortion (at 65 dBf) Mono :  
at 100 Hz :  less than 0,18%
at 1 kHz :  less than 0,15%
at 6 kHz :  less than 0,25%
Distortion (at 65 dBf) Stereo :  
at 100 Hz :  less than 0,3%
at 1 kHz :  less than 0,25%
at 6 kHz :  less than 0,3%
Alternate Channel Selectivity (at 400 khz):  50 dB
Capture Ratio:  1,0 dB
Image Response Ratio:  48 dB
Spurious Response Ratio: 70 dB
IF Response Ratio:  90 dB
Stereo Separation:
30 dB at 100 Hz
40 dB at 1 kHz
28 dB at 10 kHz
Frequency Response:  30 to 15,000 Hz
Antenna Input Impedance:  300 Ω (balanced); 75 Ω (unbalanced)
AM Tuner Section
Tuning Range:  530 to 1,600 kHz
Usable Sensitivity (bar antenna):  50 dB/m (300 µV/m)
Selectivity (±10 kHz):  33 dB
Signal-to-Noise Ratio:  46 dB
Distortion (at 30% Modulation, 80 dB/m):  less than 0,5%
General Section
Power Requirements:  100, 120, 220, 240 V, 50/60 Hz
Power Rated Consumption:  160 watts, 190 VAC
Dimensions (W x H x D):  433 x 155 x 355 mm (17-1/16" x 6-7/8" x 14")
Weight:  8,6 kg (19 lbs) net

Sennheiser HD-430 headphones

With HD-430 Sennheiser offers "new generation" headphones featuring improved magnet and sound-surround diaphragm design. Said to be "virtually distortion free", the headphones weighing only seven ounces provide audio frequency response from  16 to 20,000 Hz. Hearmonic distortion is put at less than 0,5% (DIN 45 500). This performance is achieved by use of a new diaphragm design and of a more powerful magnet weighing one-third as much as those made of conventional materials. Model HD-430 is also the first Sennheiser headphone to combine an open air design with circumaural ear cushions which lightly surround the outer ear to separate the ear from direct contact with the inner foam pad and yet permit all the advantages of openxerts a handband pressure of only about three Newtons which is an index of listener comfort. Typically. Open air headphones have half the headband pressure of conventional closed headphones, says Sennheiser. Impedance is 600 ohms per channel, and sensitivity (nominal spl at 1 kHz) is 94 dB at 1 mW input. HD-430 is provided with a 10-foot stranded-steel cable with stereo phone plug.

Performance
A very comfortable pair of headphones with very light pressure on head and ears. Suspension headband is somewhat difficult to adjust for optimum fit. Sound quality is slightly bright. Definition is exceptional. Efficiency is much higher than average, and headphones can be driven to high sound levels with relatively little power. Extremaly clean sound.

Specifications
Frequency Range:  16 Hz - 20 kHz
Impedance:  600 Ω /channel
Nominal Sensitvity SPl (at 1 kHz):  94 dB (1 mW input)
Harmonic Distortion:  less than 0,5%
Weight:  7 ounces
Cable:  10 foot cable and stereo phone plug



Kenwood KR-5400 receiver

The Kenwood KR-5400 is the most sophisticated stereo receiver ever offered at a medium price. It dlivers more power than most listeners will ever use. And it combines this performance with features and controls that rival those of more expensive separate tuners and amplifiers.
Kenwood utilizes the finest parts and materials and incorporates the most advanced engineering concepts in this fine  unit, to assure you of top performance through years of constant use. From preamp yo power amp to tumer section, the KR-5400 is a receiver you will find hard to beat.

Direct-Coupled, Pure Complementary Symmetry Output Circuitry.
Nothing comes between you and your music with Kenwood's direct coupled circuitry. Flat frequency response from ultra-lows to highest highs is assured at all power levels ip to rated output.
Large Power Transformer - Oversize heat Sinks
Kenwood's massive power transformer forms the heart of a dual positive-negative supply to symmetrically power the high output transistor stages. These are mounted on massive heat sinks for safe, cool operation even under conditions of continuous full power output. This no-compromise design assures years of stable, trouble-free performance.
Exclusive ASO Dual protection
Circuit protects both your speaker system and your receiver. Should the 'area of sale operation" be exceeded, en instant-acting relay disengages the speakers.
Three Speaker System Capability.
The KR-5400 lets you enjoy stereo in as many as three separate listening areas of your home. Listen to any one speaker system or activate two systems at once with a touch of the front panel selector switch. A front panel headphone jack adds another listening dimension.
An Advanced new preamplifier
The precision equalizer-phono preamplifier section of the KR-5400 uses low-noise metal encapsulated transistors for the ultimate in Signal-to-Noise ratio and reliability. With phono input sensitivity of 2,5 mV up to 330 mV (p-p) of input signal can be accommodated at less than 0,5% Total Harmonic Distortion. Mic input facilities on the front panel are equally noise-free and low in distortion.
Dual tape Monitor Circuits
The Kenwood dual tape facilities and individual tape monitor pushbuttons allow you to monitor two tape decks, or to dub from one deck to another while listening to program source or recorded results.
Precise Tonal Compensation
The bass and treble controls of the KR-5400 employ an ingenious multi-purpose integrad circuit. Negative feedback is used to assure no audible distortion regardless of how much tonal compensation is required to match room acoustics, speaker characteristics or program source deficiencies.
FM IF Stages.
The IF section of the KR-5400 is equipped with permanently aligned solid state filters for high selectivity, superb capture ratio, and superior AM suppression. Spurious signal rejection is more than 90 dB.
Exceptional Tuner Performance
The tuner of the KR-5400 is one of the most advanced available today. It achieves a sensitivity of 1,9 µV with an unusually sharp quieting slope to assure noiseless and distortion-free reception.
Phase-lock-Loop Multiplex Decoder
A multi-function IC, used in the stereo decoder section, operates on the phase-lock-loop principle to insure uniform separation at all audio frequencies. A newlly designed LC filter effectively reduces beat interference and intermodulation distortion normally caused by carrier leakage.
4-channel Ready
Special, inputs and outputs for connection of any four-channel decoder or adapter are provided on the KR-5440. when you are ready for quadraphonic sound, there will be no need to upset tape inputs or outputs. You retain full tape monitoring facilities for as many as two tape decks. There's even a 4-channel detector output for future discrete four-channel broadcasting when it's approved.
Specifications
FM Tuner Section
Frequency Range:  88 MHz - 108 MHz
Usable Sensitivity (IHF):  1,9 µV
Quieting Slope:   5 µV (48 dB); 10 µV (60 dB);  50 µV (70 dB)
Frequency Response:  20 Hz to 15,000 Hz +0,5 dB, -1,5 dB
Harmonic Distortion:
Mono :  0,3% (at 400 Hz, 100% modulation)
Stereo :  0,5% (at 400 Hz, 100% modulation)
Signal-to-Noise Ratio:  68 dB at 1 mV input
Image Rejection:   70 dB
Selectivity (IHF ALT channel):  65 dB
IF Rejection:  90 dB
Spurious Signal Rejection:  90 dB
AM Suppression:  70 dB
Capture Ratio:  1,5 dB
Stereo Separation:  35 dB at 1 kHz ;  25 dB at 10 kHz
Sub Carrier Suppression:  60 dB
Antenna Impedance:  300 Ω balanced; 75 Ω unbalanced
AM Tuner Section
Usable Sensitivity (IHF):  18 µV
Signal-to-Noise Ratio:  45 dB at 1 mV input
Image Rjection:  60 dB
Selectivity (IHF):  30 dB
IF Rejection:  40 dB
Antenna:  Buily-in ferrite bar antenna . External antenna terminal
Main Amplifier Section
Continuous Power Output RMS
Both Channel Driven:
35 + 35 watts into 8 Ω at 20 Hz to 20 kHz
37 + 37 watts into 8 Ω at 1 kHz
47 +47 watts into 4 ohms at 1 kHz (DIN)
Dynamic Power Output (IHF):
115 watts into 8 Ω
150 watts into 4 Ω
Total Harmonic Distortion: 
0,5% at rated power into 8 Ω
0,07% at 1/2 rated power into 8 Ω at 1 kHz
Intermodulation Distortion (60 Hz :7 kHz = 4:1): 
0,5% at rated power into 8 Ω
0,07% at 1/2 rated power into 8 Ω
Power Bandwidth:  10 Hz to 30,000 Hz
Damping Factor:  50 at 8 Ω
Frequency Response :  10 Hz - 40 kHz
Speaker Impednce:  accept 4 Ω to 16 Ω
Preamplifier Section
Input Sensitivity /Impedance:
Phono 1, 2 :  2,5 mV/50 k Ω
Aux :  150 mV/80 k Ω
Tape Play :  150 mV/80 k Ω
Mic :  2,5 mV/50 k Ω
Maximum Input Voltage (RMS)
Phono 1, 2 :  120 mV (T.H.D. 0,3% at 1 kHz)
Signal-to-Noise Ratio (IHF A Curve):
Phono 1, 2 :  70 dB
Aux :  90 dB
Tape Play :  90 dB
Mic :  65 dB
Output Voltage/Impedance
Tape Rec (Pin) :  150 mV/ 100 Ω
Tape rec (DIN) :  30 mV/80 k Ω
Frequency response
Phono :  RIAA Standard curve ±1 dB
Tone Controls
Bass :  ±10 dB at 100 Hz
Treble :  ±10 dB at 10 kHz
Loudness Control (-30 dB) :  ±8 dB at 100 Hz; ±5 dB at 10 kHz
High Filter :  -10 dB at 10,000 Hz
Low Filter :  - 8 dB at 100 Hz
General
Switches:
Speaker Selector :  Off, A, B, C,  A + B, A + C
Input Selector:  AM - FM - PHONO 1 - PHONO 2 - AUX - MIC
Mode :  Left - Right - Stereo - REV - MIX
Tape Monitor :  Source Mon - B Mon - A Play ;  Source - B Play - A Mon
Others:  Low and High Filter, Loudness, FM Muting, Mic and Phone jack
AC Outlets:  Switched 1
Power
Supply :  110 - 120 - 220 - 240 V AC, 50/60 Hz
Consumption:  340 watts at full power; 40 watts at no signal
Dimensions (W x H x D):  480 x 151 x 344 mm (18-15/16" x 5-15/16" x 13-9/16")

Weight:  11,5 kg (25,4 lbs)

Kenwood KR-6400 receiver

Main Amp and Preamp section.
The OCL type main amplifier consists of a differential amplifier in the first stage and direct-coupled, complementary symmetry amplifier circuit in every following stage. It is designed for heavy duty use and features an oversize heat sink and rugged power transistors. It is also equipped with a "sure-action" protection circuit which includes a sensitive DC current detector that protects speakers, and an ASO limiter type detector that protects power transistors by circuit breaking relay action.
The equalizer amplifier is a dual cantype, low noise operational IC amplifier which has very high stability and low distortion ratio. Every audio stage from input to output is supplied by a positive, negative dual power supply. The speakers can easily be phase shifted to correspond with Aux, Tape Play and 4CH inputs, making this receiver easily adaptable for 4-channel reproduction.

Tuner Section features;
The FM front end consists of one FET and two other transistors used in one RF stages. It also includes a frequency linear 4-gang tuning condenser.
PLL is employed in the MPX section and assures excellent channel separation and improved stability.
FM DET Out connectors are available, permetting this receiver to be ready for FM 4-channel broadcasts whenever they become available.linear scaled front dial assures fast, accurate tuning.
Specifications
FM Tuner Section
Frequency Range:  88 MHz - 108 MHz
Usable Sensitivity (IHF):  1,9 µV
Quieting Slope:   5 µV (48 dB); 10 µV (60 dB);  50 µV (68 dB)
Frequency Response:  20 Hz to 15,000 Hz +0,6 dB, -1,6 dB
Harmonic Distortion:
Mono :  0,3% (at 400 Hz, 100% modulation)
Stereo :  0,5% (at 400 Hz, 100% modulation)
Signal-to-Noise Ratio:  68 dB at 1 mV input
Image Rejection:   70 dB
Selectivity (IHF ALT channel):  65 dB
IF Rejection:  90 dB
Spurious Signal Rejection:  90 dB
AM Suppression:  70 dB
Capture Ratio:  1,5 dB
Stereo Separation:  33 dB at 1 kHz ;  27 dB at 10 kHz
Sub Carrier Suppression:  60 dB
Antenna Impedance:  300 Ω balanced; 75 Ω unbalanced
AM Tuner Section
Usable Sensitivity (IHF):  18 µV
Signal-to-Noise Ratio:  45 dB at 1 mV input
Image Rjection:  60 dB
Selectivity (IHF):  30 dB
IF rejection:  40 dB
Antenna:  Buily-in ferrite bar antenna . External antenna terminal
Main Amplifier Section
RMS Power Output
Both Channel Driven:
45 watts x 2 into 8 Ω at 20 Hz to 20 kHz
52 watts x 2 into 8 Ω at 1 kHz
65 watts x 2 into 4 ohms at 1 kHz (DIN)
Dynamic Power Output:
160 watts into 8 Ω
240 watts into 4 Ω
Total Harmonic Distortion: 
0,3% at rated power into 8 Ω
0,07% at 1/2 rated power into 8 Ω at 1 kHz
Intermodulation Distortion (60 Hz :7 kHz = 4:1): 
0,3% at rated power into 8 Ω
0,07% at 1/2 rated power into 8 Ω
Power Bandwidth:  10 Hz to 30,000 Hz
Damping Factor:  50 at 8 Ω
Speaker Impednce:  accept 4 Ω to 16 Ω
Preamplifier Section
Input Sensitivity /Impedance:
Phono 1, 2 :  2,5 mV/50 k Ω
Aux :  150 mV/80 k Ω
Tape Play :  150 mV/80 k Ω
Mic :  2,5 mV/50 k Ω
Maximum Input Voltage (RMS)
Phono 1, 2 :  120 mV (T.H.D. 0,3% at 1 kHz)
Signal-to-Noise Ratio (IHF A Curve):
Phono 1, 2 :  70 dB
Aux :  90 dB
Tape Play :  90 dB
Mic :  65 dB
Output Voltage/Impedance
Tape Rec (Pin) :  150 mV/ 100 Ω
Tape rec (DIN) :  30 mV/80 k Ω
Frequency response
Phono :  RIAA Standard curve ±1 dB
Aux, Tape Play :  10 Hz to 40,000 Hz ±1 dB
Tone Controls
Bass :  ±10 dB at 100 Hz
Treble :  ±10 dB at 10 kHz
Loudness Control (-30 dB) :  ±8 dB at 100 Hz; ±5 dB at 10 kHz
High Filter :  -10 dB at 10,000 Hz
Low Filter :  - 8 dB at 100 Hz
General
Switches:
Speaker Selector :  Off, A, B, C,  A + B, A + C
Input Selector:  AM - FM - PHONO 1 - PHONO 2 - AUX - MIC
Mode :  Left - Right - Stereo - REV - MIX
Tape Monitor :  Source Mon - B Mon - A Play ;  Source - B Play - A Mon
Others:  Low and High Filter, Loudness, FM Muting, Mic and Phone jack
AC Outlets:  Switched 1
Power
Supply :  110 - 120 - 220 - 240 V AC, 50/60 Hz
Consumption:  340 watts at full power; 40 watts at no signal
Dimensions (W x H x D):  480 x 151 x 344 mm (18-15/16" x 5-15/16" x 13-9/16")
Weight:  13,5 kg (29,8 lbs)