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

Heco Precision 200 loudspeakers

Heco precision Series loudspeakers feature a patented woofer duet claimed to ensure accurae bass response. For prcise midrange and high frequency sound, both soft dome midrange drivers and tweeters utilize a special polymer material made exclusively for Heco.
To prevent the effects of spurious vibrations, the acoustic suspension cabinets are built of particle board that is "five times more dense than usually used for speaker cabinets".
All models have two environmental contour controls, a nominal DC impedance of 8 ohms, and an efficiency control rated at 91 dB/SPL at 1 m/1W.

Type:  3-way acoustic suspension
Power Handling:  80 - 140 watts
Frequency Response:  30 - 25,000 Hz
Impedance Nominal :  4 ohms
Crossover:  700 Hz / 4,000 Hz
LF :  230 mm (9-1/4) inch Woofer
MF :  50 mm (2 inch) Midrange
HF :  19 mm (3/4 inch) Tweeter
Volume:  31,1 litre
Dimensions (H x W x D):  460 x 290 x 233 mm
Weight:  12,5 kg

Heco Precision 100 loudspeakers

Heco Precision Series Model 100

Type:  3-way acoustic suspension
Power Handling:  60 - 110 watts
Frequency Response:  35 - 25,000 Hz
Efficiency Control Rated at 91 dB/SPL at 1 m/1W.
Impedance Nominal :  4 ohms
Crossover:  1,000 Hz / 3,500 Hz
LF :  200 mm (8 inch) Woofer
MF :  38 mm (1-1/2 inch) Midrange
HF :  19 mm (3/4 inch) Tweeter
Volume:  21,2 litre
Dimensions (H x W x D):  400 x 250 x 212 mm
Weight:  9,7 kg

Kenwood KX-71R cassette deck

Auto-Reverse Computerized cassette Deck with Dolby B-C NR
Bi-directional recording/playback with quick turnaround (0,4 seconds) from rotary head system
New Dolby C noise reduction greatly improves tape noise and saturation performance
DPSS 16-programme automatic music searc-and-play system in forward and reverse
Programmed multiple repeats of single selection, one side and entire tape
Index Scan 8-second sampling of recorded music selections
Blank Search space-finder for DPSS recording
Metal tape capability
Two-colour LED peak level meters
Wow and Flutter:  0,04% (WRMS)
Signal-to-Noise Ratio:  75 dB (Dolby C, all tapes)
Frequency Response:  20 Hz - 17 kHz (Metal, CrO₂ tape)
Dimensions (W x H x D):  17-5/16" x 4-5/8" x 9-1/8"
Weight:  10,8 lbs

Kenwood KT-7X tuner

Quartz Synthesizer FM/AM Tuner with program Timer
3-way 1-hour timer with Sleep, Every day and Once functions
Quartz synthesizer automatic digital tuning system with seek
12 memory presets (6 FM + 6 AM) with 5-second scan-sample and auto memory entry
New, simplified auto-tuning system
Digital frequency readout and clock
FM Usable Sensitivity:  10,8 dBf (0,95 µV/75 Ω)
FM Signal-to-Noise Ratio;
Mono :  74 dB
Stereo :  71 dB
FM Total Harmonic Distortion:
Mono :  0,07%
Stereo :  0,09%
Dimensions (W x H x D):  17-5/16" x 2-15/16" x 12-3/4"
Weight:  8,8 lbs

Sansui XR-Q11 turntable

Minicomputerized Turntable
Sansui's model XR-Q11 turntable features an internal minicomputer that can be programmed to play up to seven selections on a record side in any desired order. After programming the unit's operation is completely automatic from initial cueing to the final arm return and motor shut-off. Electronic sensors constantly monitor the operation to ensure smooth and accurate performance, and to protect the stylus and record. It has a "fail-safe" provision that shuts the turntable down and illuminates a waring indicator in the event of a malfunction. All controls are up front and outside the dust cover for convenience and added record protection. A dual-head magnetic sensing system measures platter speed by reading magnetic pulses. It has five times the accuracy of conventional systems, according to Sansui, and triggers a fast-acting quartz-servo speed correction system. Wow and flutter have been reduced to 0,015 percent, and Signal-to-Noise ratio is 78 dB.
The tonearm is a patent pending DOB unit which makes use of optimum pivot-point technology. The straight, low mass arm is pivoted at the exact point that minimizes vibration transfer. Dynamic balance is said to be nearly perfect. The DOB arm suspension and special high-density BMC (Bulk Molding Compound) turntable base form an effective barrier against acoustic feedback. Even more feedback isolation and protection is provided by mounting the motor and arm on a rigid cast-zinc subassembly within the turntable base.
Type:  2-speed direct drive
Speeds:  33-1/3 and 45 rpm
Platter:  aluminum alloy die-cast
Diameter:  350 mm (13-3/4")
Weight:  1,7 kg (3,74 lbs(
Motor:  DC Brushless servo type; Quartz servo
Wow and Flutter:  less than 0,022% WRMS
(less than 0,015% WRMS, read out direct at the FG output)
Signal-to-Noise Ratio:  better than 62 dB (IEC B);
Rumble:  better than 78 dB (DIN B)
Tonearm:  Statically balanced type
Toneran length :  245 mm (9-11/16")
Overhang :  16 mm (5/8")
Optimum Cartridge Weight :  4 - 10 g
Power Source:  120 V, 220 - 240 V, 50/60 Hz
Power Consumption:  33 W
Dimensions (W x H x D):  483 x 142 x 420 mm (19" x 6-5/8" x 16-9/16")
Weight:  12,5 kg (27,5 lbs) net

Cartridge model SV-101
Type :  Dual magnet
Frequency Response:  10 - 20,000 Hz
Output Voltage:  2,5 mV per channel ( 1,000 Hz, 35,4 mm/sec)
Load Impedance:  47 k Ω
Tracking Force:  2 g
Stylus:  0,6 mil, diamond spherical (SN-101)

KEF Model 103.2 loudspeakers

Two way bookshelf loudspeaker
KEF Electronics RS Model 103.2 2-way bookshelf loudspeaker is said to use a 20 cm low-frequncy driver that is mechanically isolated from its enclosure to reduce the transference of inertial forces and thereby greatly reduce coloration caused by cabinet resonance. Electrical compensation is also used to improve efficiency and provide highpass signal filtering. Electronic overload protection is in the form of an automatic self-powered device called S-Stop, which is an acronymm for Steady static and Transient Overload protection. Because this protective device is so effective, the Model 103.2 is conservatively rated at 150 watts.

KEF 103.2 features:
Flat frequency response of direct sound
Minimum inter-unit time delay
Unique bass loading technique giving higher efficiency and greater power handling capacity than conventional systems
Electronic overload protection
Computer matching of component parts and drive units.
Sound Quality
KEF speakers are known the world over for their smooth, natural sound and capacity for reproducing fine detail. Their refined performance is due to a combination of unusual diaphragm materials, crossover design and careful assembly methods.. The Model 103.2 for instance is equipped with two drive units, both of which employ special plastic diaphragms and a computer designed dividing network. The intricate design procedures which KEF developed in the early seventies have been applied to every vital feature of the new speaker.
The resulting sound possesses a transparent airy quality which constantly dlights the ear and never causes listener fatigue. The precise matching of speaker pairs produces convincing stereo images of great depth and sharpness.

Bass Loading
Model 103.2 possesses some important new features which improve bass and lower mid range reproduction. The chassis of the 200 mm low frequency driver is mechanically isolated from its enclosure to reduce the transference of inertial forces and thereby greatly reduce colouration from cabinet resonance.
Electrical compensation is also incorporated in the dividing network to improve efficiency and provide high-pass signal filtering.

Electric Overload protection
The widespread use of high powered amplifiers has made it necessary to protect loudspeakers against accidental overload. KEF pioneered electronic overload protection for professional monitoring loudspeakers in the sixties and more recently developed a completely automatic self-powered device called S-STOP ( Steady State and Transient Overload Protection).
S-Stop is the most comprehensive, practical and effective protection circuit in use. It guards thermal overload, woofer over-swing and voltage surges. Immediately any sale limit is exceeded the input level is reduced by means of a relay-operated attenuator. Because S-STOP is so effective Model 103.2 conservatively rated at 150 watts.
Frequency Range:  60 Hz - 20,000 Hz ±2 dB (at 2m on design axis)[-10 dB at 37 Hz and 30 kHz]
Directional Characteristics (within 1 dB of response on design axis):
Up to 20,000 Hz :  ±5° Vertically
Up to 10,000 Hz :  ±20° Horizontally
Sensitivity Level:  86 dB SPL (anechoic condition, at 1W/1m)
Maximum Output:  106 dB SPL (on programme peaks under typical listening conditions)
Distortion Second Harmonic:
20 Hz to 150 Hz :  less than 2%
150 Hz to 20 kHz :  less than 1%
Distortion Third Harmonic:
20 Hz to 50 Hz :  less than 2%
50 Hz to 20 kHz :  less than 1%
Enclosure:  10 liters
Power Handling Capacity:
Programme Rating :  150 W
Max. Continuous Sinusoidal Input :  20 V RMS, 100 Hz - 2,5 kHz 9falling to 8 V RMS from 4 kHz - 20 kHz)
Electronic protection S-STOP:  the system is protected against any continuous or intermittent fault conditions which produce input signals not greater than 60 V peak from DC to 50 kHz
Nominal Impedance:  8 Ω
Finishes:  Choice of walnut, teak, rosewood and black ash veneers with blac or brown grille fabric as appropriate.
Dimensions (W x H x D):  265  x 510 x 240 mm
Weight:  8,6 kg (19 lbs)

Sanyo RD 5009 cassette deck

Sanyo says this RD5009 cassette deck is another "first" because it offers metal tape capability at a very small price. Other features include: Dolby noise reduction circuitry; instantaneous LED bar=graph meters to monitor input levels or playback output; full auto-stop to disengage the mechanism at the end of the cassette tape to protect both the tape and deck transport mechanism; viscous-damped cassette door; mic/line mixing; digital tape counter with reset. The RD5009 is said to deliver a frequency response of 30 to 16,000 Hz ±3 dB with metall tape. Wow and flutter is put at 0,07 WRMS
Tape Type:  Metal, CrO₂, Normal
Tape Speed:  4,75 cm/sec. (1-7/8 ips)
Recording System:  AC bias, 1/4 track stereo
Erasing System:  AC erasing, 1/2 track
Wow and Flutter:  0,07%
Frequency Response:
Normall tape :  30 - 10,000 Hz
CrO₂ tape :  30 - 14,000 Hz
Metal tape :  30 - 16,000 Hz
Signal-to-Noise Ratio (for CrO₂ tape)
Dolby On :  60 dB
Dolby Off :  52 dB
F FWD & REW Time:  approx. 90 sec (C-60 cassette)
Input Sensitivity/Impedance
Mic :  0,3 mV/ 400 oh - 10 k Ω
Line In :  50 mV / 50 k Ω
Output level/Impedance
Line out :  0,36 V / 2 k Ω
Headphone :  8 Ω - 10 k Ω
Power Source:  120 V AC, 220 - 240 V AC, 50/60 Hz
Power Consumption:  6 W ( at 120 V)
Dimensions (W x H x D):  400 x 139 x 220 mm (15-3/4" x 5-1/2" x 8-11/16")
Weight:  4 kg (8 lbs, 13 oz)

Yamaha K-950 cassette deck

Yamaha claims this model K-950 cassette deck "closes the gap" between cassette tapes and discs, in terms of performance, while still providing the traditional benefits of tape, including elimination of dirt problems and uninterrupted playback of long selections. One reason for improved performance is the capability to play metal tape. Wow and flutter rated at 0,025 perceent WRMS, results from use of an independent two-motor drive system. This spec, it's pointed out, is comparable to the drive stability of a quartz-locked turntable. Frequency Response is 30 to 22,000 Hz, 3 dB, with metal tape.
The K-950 also features a pure plasma process sendust head for better frequency response and reduced dropout and modulation noise. The use of a core/coil design and silver wires substantially lowers head impedance to provide improvend square-wave response, improved linear phase response at high frequencies,, greater dynamic range and better channel separation, according to Yamaha.
Other performance and/or convenience features include; a fluorescent bar-graph peak meter to facilitate home recording; IC logic controls; continuously adjustable bias control; timer recording switch; subsonic and MPX filters. Dolby noise reduction; a focus switch to extend high-end frequency response, or to improve phase coherance.
Track Configuration:  4-track 2-channel
Tape Speed:  4,8 cm/s ±1%
Wow and Flutter:  0,028% WRMS
Rapid  F.FWD/Rew:  75 sec. C-60 cassette
Capstan :  FG servo DC motor
Reel :  Governorless DC motor
Logic Controlled Feather Touch Operation
Full Auto Shut-Off System
2 head Recording/Playback :  pure &Plasma process head
Erase :  Ferrite head
Frequency Response Rec/Pb
LH Tape ;  30 to 17,000 Hz ±3 dB
Cr02 Tape :  30 to 19,000 Hz ±3 dB
Metal Tape :  30 to 22,000 Hz ±3 dB
Input Sensitivity.Impedance
Mic :  0,3 mV/5 k Ω
Line :  60 mV/50 k Ω
Output Level/Impedance:
Line :  340 mV/50 k Ω
Phones :  5 mW/150 Ω (1 mW)
Variable Bias Range:  ±8%
Signal-to-Noise Ratio [CrO₂]:  better than 52 dB
Overall Distortion
LH Tape :  less than 1%
CrO₂ Tape :  less than 1,5%
Metal tape :  less than 1%
Power Supplies;  120 V, 220 V - 240 V, Ac 50/60 Hz
Power Consumption:  26 W
Dimensions (W x H x D):  435 x 140 x 305 mm ( 17-1/8" x 5-1/2' x 12")
Weight:  8,8 kg ( 19,4 lbs)

JVC T-V5 tuner

PLL FM Multiplex Demodulator IC for Low Distortion and Wide Separation
IC Construction in FM/AM IF for Dependability
Wide 240 mm Frequency-Linear Tuning Dial
5-LED Signal Strength Meter for FM/AM and 3-LED Center Tune for FM
Muting and Mode Switches

FET RF Amplifier in Fronted
 a high-performance 3-gang variable capacitor and an FET RF amp are found in the FM frontend of the T-V5. They team up to give remarkable performance constancy anywhere, anytime. When signals are weak capture is strong. When signals are strong, suppression of interference is especially good so that crossmodulation and intermodulation distortion are better controlled. Tarcking between the variable capacitor and the tuning pointer is critically matched for tuning accuracy.

Low-Noise / Low-Distortion FM IF IC
All the important circuits for IF, including an IF amp, quadrature detector AFC/AGC circuits, etc., are included in an improved IC taking advantage of all the latest microelectronic techniques. An array of ceramic filters reduces group delay distortion. Thus the T-V5 boasts specifications much better than those found in competing models; less than 0,15%/0,3% (mono/stereo) Total Harmonic Distortion; 82 dB Signal-to-Noise Ratio ratio ; 45 dB stereo separation; 65 dB selectivity and so on, impressive.
Low-Noise / High-Separation FM Stereo IC
Multiplex demodulation for stereo FM signals requires high precision indeed if hi-fi musicality is to be maintained JVC has been in the lead of stereo FM electronics since the beginning, and we've developed a new, improved IC containing the FM MPX of the PLL type. It promises low didtortion and wide channel separation. And best of all, it never requires realignment and is never affected by external, environmental changes or the passage of time.

Self-Contained IC for AM
Even the AM section has been refined for better sound A third IC contains the RF and IF amps for AM, highlighting low noise and low distortion. A new ceramic filter in the IF improves AGC (Automatic Gain Control); whatever the strength of the incoming AM signal sound reproduction is always ideally clean.
FM Section
Usable Sensitivity:  10,3 dBf (0,9 µV / 75 Ω )
50 dB Quieting Sensitivity
Mono :  14,8 dBf
Stereo :  36,3 dBf
Signal-to-Noise Ratio
Mono :  82 dB
Stereo :  70 dB
Frequency Response
50 Hz - 15 kHz (+0,5 dB  -1,0 dB)
30 Hz - 17 kHz (+0,5 dB  -2,0 dB)
100 Hz :  0,15% (mono); 0,3% (stereo)
1 kHz :  0,15% (mono);  0,3% (stereo)
6 kHz :  0,4% (mono); 0,8% (stereo)
Capture Ratio:  1 dB
Alternate Channel Selectivity:  65 dB (±400 kHz)
Spurious Response Ratio:  75 dB (at 98 MHz)
Image Response Ratio:  60 dB (at 98 MHz)
IF Response Ratio:  90 dB (at 98 MHz)
AM Suppression Ratio:  55 dB
Stereo Separation:  45 dB (1 kHz), 35 dB (50 Hz - 10 kHz)
SCA Rejection Ratio:  70 dB
Muting Threshold:  25,2 dBf
Stereo Automatic Switching Level:  600 mV/3,3 k Ω
Antenna Impedance:  75 Ω  (unbalanced)
AM Section
Usable Sensitivity:  30 µV
Signal-to-Noise Ratio:  50 dB
Selectivity:  45 dB (±10 kHz)
Image Response Ratio:  45 dB
IF Response Ratio:  40 dB
Output Level:  250 mV
Antenna:  Built-in ferrite core bar antenna
Dimensions (W x H x D):  420 x 108 x 313 mm ( 16-1/2" x 4-1/4" x 12-4")
Weight:  3,7 kg (8,16 lbs)

JBL L 112 loudspeakers

J.B. lansing claims that these L112 bookshelf loudspeaker system are  of "state-of-the-art." 3-way design, partly beacuse they are designed as "mirror-imaged pairs". The L-112 features a new 1-inch dome radiator, a 5-inch midrange speaker and a 12-inch low frequency transducer. A new, high-resolution dividing network provides smooth transition between the drivers, controlling each throughout its entire operating range. The woofer utilizes JBL's unique Symmetrical Field geometry flux-stabilized magnetic structure ; it delivers deep, extended low frequency response according to JBL. A powerful magnet weighing more than 10 pounds and a 3-inch copper edge wound voice coil contribute to high power handling capability, low distortion and "outstanding" transient response. The midrange is housed in an isolated subchamber to prevent interaction with the low frequency driver. A new dome radiator is said to reproduce the highest harmonics with power and clarity.
The system's enclosure measures 21-1/2 inches by 14-1/4 inches by 13 inches, and is constructed of dense compressed wood panels veneered in American black walnut and lined with fibreglass to absorb unwanted resonances.  The speaker can be driven by any amplifier delivering from 10 to 300 watts continuous sine wave per channel.
 new Dome Radiator
Designed specifically for the L112, the new high frequency dome radiator has the extraordinary ability to acurately reproduce the highest harmonics - the subtlest shadings of music -  with depth. Yet it clenly handles the loudest musical peaks with authority. In developing this transducer, we utilized the capabilities of our fully equipped laser-optics laboratory. Highly detailed holograms (three-dimensional photographs) allowed us to study diaphragm motion and identify flaws that would have otherwise gone undetected (much the way X-rays aid a doctor). The high-frequency dome of the L112 is formed of a lightweight phenolic material, coated with aluminum by means of a vaper deposition process. The dome has the optimum combination of strength, mass, and rigidity, and a copper voice coil drives it over the full circumference for smooth, low-distortion response acros its entire wide operating range.

SFG - Cleaner, More Powerful Bass
The 300 mm 912 in) low frequency transducer of the l112 utilizes JBl's unique SFG (Symmetrical Field Geometry) magnetic structure to produce deep, powerful, clean bass. The SFG innovations - the symmetrical magnetic field at the voice coil gap and the aluminum Flux Stabilizing Ring - dramatically reduce the second harmonic distortion found in conventional drivers. A powerful magnet and large 75 mm (3 in) voice coil give the driver high power-handling capability, further reduction of distortion, and outstanding transient response. The thick white coating on the cone is an exclusive JBL, formulation that gives the cone the optimum mass and stiffness for flatest frequency response.
Max. Recommended Amplifier Power:  300 watts per channel
Nominal Impedance:  8 Ω
Crossover Frequencies:  1,2 kHz, 3,7 kHz
System Sensitivity:  89 dB SPL, 1 W/1 m
Low Frequency Driver
Nominal Diameter :  300 mm (12")
Voice Coil :  76 mm (3") copper
Magnetic Assembly Weight:  4,7 kg (10,25 lb)
Flux Density:  1,05 tesla ( 10,500 gauss)
Sensitivity :  89 dB SPL
Midrange Driver
Nominal Diameter :  130 mm (5")
Voice Coil :  22 mm (7/8") copper
Magnetic Assembly Weight:  0,74 kg (1,62 lb)
Flux Density:  1,4 tesla ( 14,000 gauss)
Sensitivity :  91 dB SPL
High Frequency Dome Radiator
Nominal Diameter :  25 mm (1")
Voice Coil :  25 mm (1") copper
Magnetic Assembly Weight:  0,9 kg (2 lb)
Flux Density:  1,4 tesla ( 14,000 gauss)
Sensitivity :  89 dB SPL
Finish/Grille Colors:  Oiled walnut /  brown
Dimensions (W x H x D):  622 x 362 x 333 mm (24-1/2" x 14-1/4" x 13")
Weight (shipping):  25 kg (55 lb)

Sony TA-F 220 amplifier

Integrated Stereo Amplifier System:
Preamplifier :  Low-noise, High-gain equalizer amplifier
Power Amplifier ;  Pure-complementary SEPP OCL power amplifier with all stages directly coupled
Continuous PowerOutput RMS (both channel driven simultaneously):
70 W + 70 W at 4 Ω (DIN, 1 kHz)
70 W + 70 W at 8 Ω (DIN, 1 kHz)
50 W + 50 W at 8 Ω ( 20 Hz - 20 kHz, T.H.D. 0,05%)
Input Sensitivity/Impedance
Phono (MM) :  2,0 mV/50 k Ω
Tuner, CD, Video, Aux, Tape, DAT :  150 mV/ 50 k Ω
Signal-to-Noise Ratio (weighting network, input level)
Phono (MM) :  70 dB (A, 2 mV)
Tuner, CD, Video, Aux, Tape, DAT :  100 dB ( 150 mV)
Total Harmonic Distortion:  less than 0,05% at rated output
Intermodulation Distortion (60 Hz :7 kHz = 4:1):  less than 0,05% at rated output
Frequency Response:
Phono :  RIAA equalization curve ±0,5 dB
Tuner, CD, Video, Aux, Tape, DAT :  7 Hz - 100 kHz ±3 dB
Residual Noise:  less than 170 µV (network A)
Damping Factor:  40 ( 8 Ω, 1 kHz)
Output Level / Impedance:
Rec Out :  150 mV/ 1 k Ω
Speakers :  4 - 6 Ω / 8 - 16 Ω
Headphones :  Accepts low/high impedance
Tone Controls
Bass Control
Response ;  ± 7 dB at 100 Hz
Turnover Frequency :  500 Hz
Treble Control
Response :  ±8 dB at 15 kHz
Turnover Frequency :  3 kHz
Loudness (Attenuation 30 dB):  +6 dB at 100 Hz ; + 3 dB at 10 kHz
Power Requirements:  220 V / 240 V AC, 50/60 Hz
Poer Consumption:  150 W (220 V); 380 W (240 V)
Dimensions (W x H x D):  430 x 135 x 315 mm ( 17" x 5-3/8" x 12-1/2")
Weight:  7,4 kg (16 lb 5 oz)

Denon PMA-550 amplifier

Denon Integrated Amplifier model PMA-550 is rated at 100 watts per channel, with both channels driven into 8 Ω, and a total harmonic and intermodulation distortion below 0,005 percent. The unit may be direct-coupled from input to output by means of a front-panel switch, and it incorporates electronic switching for input sources, a separate record-out selector that permits the user to listen to one source while recording another, a subsonic filter, defeatable tone controls, and switching for two sets of speakers. Phono overload levels are 160 millivolts for the moving-magnet, and 8 millivolts for the moving-coil phono sections. Phono Signal-to-Noise ratios are 89 dB for MM and 73 dB for MC.
Rated Output (both channels driven): 
100 W + 100 W (20 Hz - 20 kHz, 8 Ω, T.H.D. 0,005%)
140 W + 140 W (1 kHz, 4 Ω, )
Total Harmonic Distortion:  less than 0,005%
Intermodulation Distortion:  less than 7 kHz/60 Hz :1/4, 0,008% (at amplitude output) equivalent to rated output)
Power Bandwidth:  5 Hz - 100 kHz (IHF T.H.D. 0,035%)
Transmission Characteristics:  1 Hz - 400 kHz +0 -3 dB ( at 1 W output)
Input Sensitivity:  150 mV
Input Impedance:  40 k Ω
Output Impedance:  0,1 Ω ( 1 kHz)
Signal-to-Noise Ratio (IHF A Network):  108 dB ( Input terminals short circuited)
Output Terminals:  
Speaker :  A & B load 4 - 16 Ω,  A + B load 8 - 16 Ω
Equalizer Amplifier Output (Rec Out Terminal):
Maximum Output :  10 V (at 50 k Ω load)
Rated Output :  150 mV
Total Harmonic Distortion :  bellow 0,001% ( at 1 kHz, 8 V output)
Input Sensitivity/Impedance:
Phono 1 (MM) :  2,5 mV/ 50 k Ω
Phono 2 (MC) :  125 µV/100 Ω
Tuner :  150 mV/40 k Ω
Aux, Tape :  150 mV/40 k Ω
RIAA Deviation:
Phono 1 (MM) :  within ±0,2 dB ( 20 Hz - 100 kHz)
Phono 2 (MC) :  within ±0,2 dB ( 20 Hz - 100 kHz)
Signal-to-Noise Ratio (IHF A Network):
Phono 1 (MM) :  90 dB ( input terminals short-circuited at 2,5 mV inpit)
Phono 2 (MC) :  73 dB (input terminals short-circuited at 250 µV input)
Tuner, Tape, Aux :  108 dB ( input terminals short-circuited)
Tone Control
Bass :  100 Hz ±8 dB
Treble :  10 kHz ±8 dB
Equalizer Subsonic:  18 Hz , 6 dB/oct
Loudness Characteristics:
Low Frequency :  100 Hz +7 dB
High Frequency :  10 kHz +6 dB
Power Source:  AC 120 V, 60 Hz ; 220 - 240 V 50/60 Hz
Power Consumption: 740 W at maximum output (IEC)
Dimensions (W x H x D):  434 x 132 x 407 mm
Weight:  13,5 kg

Nikko Alpha 130 power-amp

Nikko Power Amplifier 130
Continuous Power Output per Channel:
More than 100 watts  - 20 -20,000 Hz at 8 Ω
More than 100 watts - 20 - 20,000 Hz at 4 Ω
More than 120 watts - 1000 Hz at 8 Ω
More than 130 watts - 1000 Hz at 4 Ω
Total Harmonic Distortion :
Continuous Power Output  at 8 Ω :   no more than 0,01%
Continuous Power Output  at 4 Ω :  no more than 0,03%
1 Watt power Output (8 ohms):  no more than 0,01%
Intermodulation Distortion :
Continuous Power Output  at 8 Ω :  no more than 0,01%
1 Watt Power Output :  no more than 0,03%
IHF Power Bandwidth (8 ohms):  10 - 50,000 Hz
Damping Factor at 1000 Hz (8 ohms):  more than 50
Frequency Response (Normal Input 8 Ω)
At 1 Watt Power Output :  10 - 50,000 Hz  ±0,2 dB
Input Sensitivity for 120 watts Power Output
Main In :  1 V ±2 dB
Signal-to-Noise Ratio (IHF A network):
Main (Normal, Direct) :  better than 110 dB
Signal-to-Noise Ratio (DIN Filter):
Main IN (Normal, Direct) :  better than 90 dB
Channel Balance:  no more than 1 dB
Residual Hum and Noise, 8 Ω:  no more than 0,5 mV
Idling Current:  20 - 60 mA
Midpoint Voltage:  0 ±20 mV
Muting Delay Time:  3 - 7 seconds
Power Requirements:
W-type :  AC 120 V, 60 Hz
E-type :  AC 220 V, 50 Hz
B-type :  AC 240 V, 50 Hz
Power Consumption:  310 W (420 VA)
Dimensions (W x H x D):  482 x 138 x 344 mm (19" x 5-1/3" x 13-1/2")
Weight:  12 kg (26,5 lbs)

Nikko Alpha 220 power-amp

Nikko Audio's Alpha 220 is a 120 watts per channel power amplifier having a DC servo-feedback loop, non-switching output circuitry, and a high slew rate The unit's input circuitr uses dual field effect transistors (FEDs) for lowest noise and distortion; the remaining stages employ wideband bipolar transistors. The amplifier has a slew rate of 100 volts per microsecond and a rise time of one microsecond. Low frequency signals are monitored and corrected by a DC servo-feedback loop.
The output stage is operated in a continuous non-switching mode, using circuitry that tracks transistor bias in synchonization with the music signal, to avoid excessive heat generation and resultant cost associated with traditional Class A designs while nonethless offering the exceptional degree of sonic clarity and openness of Class A operation. Additional features include; protection circuits to prevent speaker damage even if the preamp has a DC offest signal; front panel headphone jack and speaker selector switches; indicator lamps that monitor power-on and protection-circuit status.
Continuous Power Output per Channel:
More than 120 watts  - 20 -20,000 Hz at 8 Ω
More than 130 watts - 20 - 20,000 Hz at 4 Ω
More than 120 watts - 1000 Hz at 8 Ω
More than 130 watts - 1000 Hz at 4 Ω
Total Harmonic Distortion :
Continuous Power Output  at 8 Ω :   no more than 0,008%
Continuous Power Output  at 4 Ω :  no more than 0,02%
1 Watt power Output (8 ohms):  no more than 0,02%
Intermodulation Distortion :
Continuous Power Output  at 8 Ω :  no more than 0,01%
1 Watt Power Output :  no more than 0,02%
IHF Power Bandwidth (8 ohms):  5 - 70,000 Hz
Damping Factor at 1000 Hz (8 ohms):  more than 60
Frequency Response (Normal Input 8 Ω)
At 1 Watt Power Output :  10 - 100,000 Hz +0, -1 dB
Input Sensitivity for 120 watts Power Output
Main In :  1 V ±2 dB
Signal-to-Noise Ratio (IHF A network):
Main (Normal, Direct) :  better than 105 dB
Signal-to-Noise Ratio (DIN Filter):
Main IN (Normal, Direct) :  better than 90 dB
Channel Balance:  no more than 1 dB
Residual Hum and Noise, 8 Ω:  no more than 0,5 mV
Idling Current:  40 - 120 mA
Midpoint Voltage:  0 ±20 mV
Muting Delay Time:  3 - 7 seconds
Power Requirements:
W-type :  AC 120 V, 60 Hz
E-type :  AC 220 V, 50 Hz
B-type :  AC 240 V, 50 Hz
Power Consumption:  480 W (620 VA)
Dimensions (W x H x D):  482 x 138 x 344 mm (19" x 5-1/3" x 13-1/2")
Weight:  13,5 kg (29,7 lbs)