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

Torino 2014 Gran Galà dell’Alta Fedeltà

Saturday 1 and Sunday 2, returns a Torino the new appointment of "Gran Galà dell’Alta Fedeltà" at Hotel NH Lingotto di Torino, organized by Giulio Cesare Ricci. 

NAD 3020

 The NAD (New Acoustic Dimension) brand name has existed in Europe for about many years but is probably unfamiliar to most American audiophiles. NAD is an unusual company, involving an international group of independent dealers whose needs and suggestions play a major part in the development of its products, which are designed to sound as good as the state-of-the-art. Permits and to sell at prices within the reach of a broad segment of the buying public.
In designing its Model 3020 integrated amplifier. NAD began with the assumption that, for a given power-output level, a state-of-th-art. Unit need not cost significantly more than a poor or mediocre one. They focused on the design areas that can cause listening problems - for example, protective circuits that cause distortion with very low or highly reactive speaker loads, phono preamplifiers whose circuits interact with phono-cartridge inductance to affect high-frequency response, and circuits whose excessive bandwidth mekes them vulnerable to interference from radio transmitters and overload from infrasonic turntable rumble or disc warps.
 The NAD 3020 is a no-frills, moderately-prieced amplifier designed to provide state-of-the-art. Performance at volume levels far in excess of what would be expected from its conservative 20-watt per channel power rating. This remarkable characteristic is made possible by high-voltage, high-current output stages which can deliver short-term burst of two to five times the rated continuous power output into loudspeakers of widely varying impedances. The 3020's exclusive "Soft Clipping" circuit permits listening levels even beyond these limits by reducing harshness aat high volume settings.
The phono preamplifier section of the 3020 contains a sophisticated 6=transistor circuit which has been enginereed for extremely low noise and nearly distortion-free performance. Built-in infrasonic and ultrasonic filters further reduce the interference of non musical signals caused by turntable rumble, floor vibration, tone arm or stylus resonances.
These uniquely designed input and output stages combine to create an inexpensive amplifier which is easily capable of driving the very best loudspeakers.
 Designed for Real_Word Performance
If you read specificatoions and test reports you will find that the majority of modern amplifiers measure well on the test bench, with impressive figures for signal-to-noise ratio, power output at 8 ohmsm and ultra-low harmonic distortion. But outside the laboratory many of these products don't perform as well as their specifications suggest. In the home you don't listen tosignal generators and 8 ohms test resistors; you listen to complex musical waveforms generated by phono cartridges and reproduced through loudspeakers whose impedance is seldom 8 ohms.
Rather than incorporating costly refinements that may test well, but yeld little audible improvement, NAD's engineers have designed the 3020 for optimum performance in every day use.
 Effective Control Features
Like every other part of its design, the 3020's controls have been carefully considered for genuine usefulness. The Bass and Treble controls are tailored for musically effective response in the high and low frequencies without altering the critical mid-range tonal balance.
For listening at low volume levels or with sensitive headphones, the 3020's Audio Muting button reduces levels by 20 dB, expanding the useful range of the Volume control and subduing any residual circuit noise. A simple, elegant set of five LED's accurately displays the peak power level which the amplifier is delivering to the loudspeakers, form 1 to 35 watts into 8 ohms or 2 to 70 watts into 4 ohms. The circuit monitors both channels and displays the higher output at each instant.
 High-Performance Design
Wide Range Phono Preamplifier
In a moderately priced amplifier you might expect to find an economy preamp circuit, but the NAD 3020 contains a phono preamp stage which is audibly identical to the finest separate professional preamps. The 3020 preamp interfaces correctly with the impedances of real phono cartridges (as many preamps do not), it is quiet enough for use with either moving-magnet or high-output moving-coil pickups, and its distortion is extremely low, not only with sine-wave test tones but also when reproducing complex high-level music signals. The 3020 was designed to achieve the best signal/noise ratio when a cartridge is plugged in (rather than with the usual, but inappropriate, short-circuit input). The total dynamic range of the 3020 is typically 107dB, ample even for the digitally-mastered recordings of the 1980s.

Infrasonic and Ultrasonic Filters
Audio signals are often contaminated with interference at frequencies below and above the audible range, such as acoustic feedback, disc warps and radio interference. Amplification of such signals yields no sonic benefit, wastes amplifier power, and may cause intermodulation distortion muddy bass, excessive woofer cone motions, and even tweeter burnout. The NAD 3020 contains a precise, minimum-phase audio-bandpass filter which strips off such interference and preserves a clean musical waveform.
 Dual-Mode Power Supply
The power supply circuit for the output stage is only loosely regulated, so it is free to supply the high voltages needed for a high IHF headroom factor (at 8 ohms) and also to supply the large currents at lower voltages needed for driving low-impedance loads (down to 2 ohms). An entirely separate power supply circuit, operating from another secondary winding on the power transformer, supplies extremely stable, noise-free, regulated operating voltages for the preamplifier and tone control stages; thus distortion and blurring of the stereo image due to power supply modulation cannot occur in the 3020. The NAD 3020 has earned a world-wide reputation among audio reviewers for its sensible and efficient design and superb performance.
Numerous test reports, comparing the 3020 with equipment of far greater power rating and cost have proven the 3020 to be an outstanding value.
 The power supply for the NAD 3020 output stages is loosely regulated - that is, when there is little or no audio signal present, the supply voltage is relatively high, giving the amplifier a large short-term power-output capability (which is reflected in its very high IHF dynamic-headroom rating). A heavy load, whether from high average signal levels or from aa very low load impedance, causes the power supply voltage to drop, limiting the current through the output transistors to a safe value.
Pre-Amp Section
Phono Input
Input Impedance (R and C):  47 kΩ/ 47pF
Input Sensitivity (1kHz):  2.5 mV ref. 20W
Signal-to-Noise Ratio (A-weighted with cartridge connected):  75 dB ref. 5mV
Line Level Inputs
Signal-To-Noise Ratio (A-weighted ref 1W):   greater than 86 dB
Channel Separation:  greaer than 60 dB
Frequency Response:  20 Hz - 20 kHz (±0.5 dB)
Infrasonic Filter:  -3 dB at 15 Hz, 24 dB/octave
Ultrasonic Filter:  -3 dB at 35 kHz, 12 dB/octave
Power  Amp Section
Continuous Output Power (into 8 W )*:  20 W (13 dBW)
Rated Distortion (THD 20Hz - 20kHz):  0.02%
Clipping Power (maximum continuous power per channel):  30W
IHF Dynamic Headroom (at 8W):  +3 dB
IHF Dynamic Power (maximum short term power per channel):
40 W at 8 Ω
58 W at 4 Ω
72 W at 2 Ω
Physical  Specifications
Dimensions (W x H x D):  420 x 96 x 240 mm
Net Weight:  5,3 kg

Shipping Weight:  6,7 kg

B&W DM-550

 Following on from B&W's highly acclaimed and successful 100 Series, the DM550 digital monitor takes full advantage of a whole new generation of design technology to produce improved performance with a higher frequency range and lower colouration.  With its aesthetically pleasing styling, your DM550 is designed to anticipate individual preferences and match all types of environment.
System parameters for the B&W 500 Series have been optimised by the extensive use of computer aided design to ensure efficient and extended low frequency performance. To achieve the goal of flatter response curves and lower colouration, totally new drive unis have been designed - benefiting from the use of finite element predictions of cone behaviour and laser interferometer assessment of prototypes. Quite deliberately, the B&W 500 Series of loudspeakers are described as digital monitors. They have been designed for the age of the compact disc, with all the additional requirements that this material places on the loudspeaker system - such as increased dynamic range, increased transient information, lower noise floor, etc. B&W DM550 is however, just as much at home with good analogue material and essentially will faithfully reproduce whaatever signals are fed to it.
 Stand-mount/Bookshelf loudspeaker system
The tailored two-way closed box design incorporates a 6" bass/midrange driver with a large magnet assembly thrusting high pressure sound reproduced to precise limits dictated by the dimensions of small enclosure.
A one piece moulding has been used to strengthen the cabinet rigidity between drivers and front baffle. The metal-domed high frequency unit dictated by CAD allows the simplest of crossovers to be used. All of which increases cost-effectiveness without impairing linearity.
 Technical highlights
B&W's Tweeter technology ensures that the sound remains focused and time sensitive and that the stereo image is presented with unparalleled three dimensional accuracy.
The cabinets feature a specially designed high density front baffle which achieves almost Matrix-like stability in strengthening overall enclosure construction. The bevel edges of the front moulding reduce diffraction and improve dispersion.
The crossover components use heavy gauge wire throughout and new drivers guarantee not only high reliability but ensure that top specifications are met
 The design brief for DM550 called for a small and cost-effective loudspeaker that could be incorporated unobtrusively into the home, while still possessing the linearity and bass extension of true monitor system.

The drive units
The two-unit closed box alignment chosen for DM550 employs a specially designed 160 mm (6") bass driver, with 26 mm (1") high temperature voice coil. This enables a simple crossover to be employed which not only increases cost effectiveness but retains system linearity.
The new metal-domed tweeter uses the same diaphragm as the highly acclaimed Matrix 801 Series 2, and gives true piston behaviour up to frequencies in excess of 20 kHz. And like all B&W components, it's B&W made.
The enclosure
The expertise B&W have gained with cabinet technolgy following the invention of the B&W Matrixx Series has enabled us to reduce unwanted cabinet vibration. In the case of the 500 Series  our attention has been focused on the front baffle construction, and we make full use of modern structural plastics, to both strengthen and enhance the appearance.
 The crossover
Sophisticated computer technology has enabled B&W  to optimise each component in the crossover network at the design stage. Every production sample is also computer-tested to close tolerance, ensuring that each loudspeaker faithfully reproduces the original design specifications.

Overload protection
A 2-amp quick-blow fuse protects the system against excessive input of normal musical signals. However, certain abnormal signals, particularly those containing only high frequencies, could damage the tweeter. The usual precautions, such as turning off the amplifier before connections are made, should be observed. The fuse is located in the rear of the cabinet.
Frequency Range:  56 Hz to 30 kHz (-6 dB points)
Bass Loading:  Second-order closed box alignment
Frequency Response:  75 Hz 20 kHz, ±2,5 dB on reference axis
Dispersion:  20 Hz to 15 kHz
Vertical :  ±2 dB over 10° arc
Horizontal :  ±2 dB over 40° arc
Sensitivity:  87 dB (2,83 V/ 1 m)
Distortion (For 90 dB at 1 m)
Second Harmonic :
Less than 3% at 20 Hz to 200 Hz
Less than 1% at 200 Hz to 20 kHz
Third Harmonic:
Less than 2% at 20 Hz to 200 Hz
Less than 1% at 200 Hz to 20 kHz
Impedance: Nominal 8 Ω (not faling below 4 Ω)
Crossover:  third-order acoustic response low-pass and high-pass
Drive Units:
1 x 26mm high-frequency with aluminium dome, One 26mm coil on aluminium former, wound with polymide resin and heat cured
1 x 160mm bass/midrange with composite short fibre, 26mm coil on high temperature former, wound with polymide resin and heat cured
Power Handling:  Suitable for amplifiers with 10 W to 75 W output
Dimensions (H x W x D):  352 x 204 x 243 mm (13-7/8" x 8" x 9-1/2")
Weight:  5,5 kg  (12 lbs)

Cabinet Finish:  Simulated veneers of walnut or black ash

Akai AA-6300

 Akai's AA-6300 Solid State Am/FM Multiplex Stereo Receiver with FET for improved FM sensitivity and IC for high Selectivity is designed especially for the low budget buyer seeking a high-quality tuner-amplifier. Among the outstanding features of this versatile instrument are:
FET (Fiel Effect Transistor) Front End for improved FM sensitivity.
IC (Integrated Circuit) in IF stages for high selectivity.
80W (40W per channel) Music Power
AM/FM Signal Strength Meter
Automatic FM Stereo/Monaural Switching
Speaker System Selector
Tape Monitor and Monitor Switches
Bass, Treble and Loudness Control
Stereo Headphone and DIN Jacks
FM Tuner Section
Frequency Range:  88 to 108 MHz
Sensitivity (IHF):  2,0 µV
Signal-to-Noise Ratio:  better than 65 dB
Selectivity: better than 50 dB
AM Tuner Section
Frequency Range:  535 to 1605 kHz
Sensitivity (IHF):  20 µV at 1 MHz
Signal-to-Noise Ratio:  better than 50 dB
Selectivity:  better than 20 dB
Amplifier Section
Frequency Response:  20 Hz to 40,000 Hz (-3 dB)
Output Power:  80 W at Music Power
Dimensions (W x H x D):  445 x 133 x 340 (17-1/2" x 5-3/4" x 13-1/2")

Weight:  10,4 kg (22,5 lbs)

Akai AA-6200

 Akai AA-6200 all Silicon Transistorized Solid State FM/AM Multiplex Stereo Tuner-Amplifier with Two Integrated Circuits.
Simplified controls for easier operation
Attractive black and silver front panel design.

Outstanding Features:
FM and AM Sections - Ceramic Filters for better selectivity.
Field Effect Transistor front end for extra sensitivity
FM Center Tuning and FM/AM Signal Strength Meter
Stereo Indicator Lamp
4-Stage FM IF Amplifier
AM Bar Antenna
2 AC Outlets for extra convenience
40 W Music Power
Tape Monitor and Stereo/Mono Switches
Loudness Control
Bass, Treble and balance Controls
Headphone and DIN Jacks
Universal Voltage Selector
FM Tuner Section
Frequency Range:  88 to 108 MHz
Sensitivity (IHF):  2,5 µV
Signal-to-Noise Ratio:  better than 60 dB
Stereo Separation:  better than 33 dB
Selectivity: better than 60 dB
AM Tuner Section
Frequency Range:  535 to 1605 kHz
Sensitivity (IHF):  25 µV at 1 MHz
Signal-to-Noise Ratio:  better than 50 dB
Selectivity:  better than 20 dB
Amplifier Section
Frequency Response:  20 Hz to 50,000 Hz (-3 dB)
Output Power:  40 W at 4 Ω ; 15 W at 8 Ω
Harmonic Distortion:  0,2%
Input Sensitivity:
Phono :  3 mV
Aux, Tape :  150 mV
Signal-to-Noise Ratio: 
Phono :  better than 60 dB
Aux, Tape :  better than 70 dB
Dimensions (W x H x D):  445 x 133 x 340 (17-1/2" x 5-3/4" x 13-1/2")

Weight:  8,4 kg (18,5 lbs)

Kenwood KA-6004

 Exceptinal Stability of Amplification achieved Constant Current Driving System
The KA-6004 achieves an over-all high level of reliability in every performance phase. If only the strictest requirements are met by each component, then they are included in the full assembly potential of this outstandingly unique amplifier. For example, the pre-amplifier uses a new type of can seal (metal cased) transistor which is capable of off-setting usual characteristic deterioration in S/N ratio resulting from humidity and temperature wear. Low noise PNP transistors have been attached to the top of the equalizer circuit. Also, super-high nichrome evaporated metal film resistors have been used in the feedback circuit in the equalizer stage. Each error thus occurs only within ±1%. These same resistors are also only equipped in all other significant circuits to vastly improve S/N and block S/N age deterioration.
 Linear Frequency Power Output Kept 40 W in 20 Hz to 20 kHz
Kenwood has been improved in output indication. In the conventional way, output was indicated in just one point of 1 kHz. However, in Kenwood's latest way of improving over-all quality guaranteed output is indicated in the entire range of audio frequency of 20 Hz to 20 kHz, i.e. the output is indicated in "minimum point", but not in "maximum point".
The maximum output is a performance figure that implies the dynamic range of the power amplifier, therefore, only the output of 1 kHz will imply the imperfect performance of the amplifier because the output of any amplifier is usually best near 1 kHz. However, as described in the preceding, KA-6004 has the circuits to allow the simultaneous indication of entire performance. With an all stages direct-coupled circuit provided, the output linearity in low pass will be shown by power output data
 Higher Reliability Achieved by Strictly Selected Components
The pre-amplifier employs a new type of can seal transistors that are capable of precluding the characteristic changes, i.e. the characteristic deterioration of S/N caused by humidity and temperature. At the top of equalizer circuit, low noise type PNP transistors are equipped.  The feedback circuit in the equalizer stage employs super-high precision nichrome evaporated metal film resistors, each error within ±1%. The nichrome evaporated metal film resistors are equipped in all other important circuits to prominently improve S/N and preclude age deterioration of S/N.
Pure-complementary Circuit + Constant Current Driving
The KA-6004 employs Kenwood's exclusive Constant Current Driving system in the pure-complementary and direct coupling driver stage. The highest stability in the amplification is now obtainable. By minimizing crossover distortion and by improving phase characteristics, the KA-6004 guarantees superb performance quality from ultra low range to far above the limit of audio frequency. It also prevents performance from deterioration caused by the deviation in power voltage. Kenwood has overcome the last problem-instability-remaining in direct coupling amplification. The refined reproduction is fully enjoyable.
Protection Circuit
All stages direct-coupled circuit in KA-6004 includes constant current driver circuit capable of amplifying from DC. The driving way will amplify faithfully the superlow pass, i.e. plus  minus several Hz of the frequency picked up by cartridge on bowed record plate and wow-fluttered turntable, thus the faithful amplification will permit unnecessary critical load on speaker. In addition, if direct current input should be applied, burning of voice coil may by caused.  To prevent the preceding troubles in KA-6004, a protecting circuit is employed to cut superlow pass of 10 Hz or less in order to protect speaker against overload.
 Exceptional Dynamic Range
The equalizing stage of preamplifier has been entirely redesigned to obtain exceptionally wide dynamic range. The KA-6004 assures 420 mV p-p maximum input level (at 1 kHz). Any fortissimo peak can faithfully reproduced without saturation. Further, thanks to the minimized RIAA deviation of within ±0,2 dB, playback with real high fidelity is guaranteed.

Attenuator Type Tone Control
Attenuator is employed in tone control, +10 dB to -10 dB is covered by 2 dB controlled. Left and right characteristics are correctly coincided, so that no unbalance will be caused in tone control.
In conventional volume type, frquency characteristic is not perfectly flat even at zero degree, but is waved. In KA-6004, with tone control positioned at "Off", tone control circuit is neglected, so that frequency characteristic is kept correct.

Noise Filter
Low cut filter has two turnover points, i.e. 40 Hz and 80 Hz controlled, and sharp attenuation characteristic of 12 dB/oct. The filter will also protect speaker, with protection circuit associated, againt large signal inputted in low pass.
High cut filter has a higher turnover point, i.e. 7 kHz which will reduce noise only without damaging desired tone, and an easy attenuation characteristic of 6 dB/oct.

Input Selector
The KA-6004 is versatile for input program sources. It features input jacks for 2 pairs of phono, 2 pairs of Aux, tuner and microphone.  A program source on operation is shown by luminous indicator on the front panel.

Two Systems of Tape Monitor
Two systems of tape monitor circuits, i.e. A and B are provided to allow simultaneous activation of two decks.  Mutual dubbing is easily allowed by switching only.

Microphone Input
Mic input terminals are equipped on front paanel, so that right-side two systems of microphones will allow so easier operation. Since selector positions are independent, the input may be used sufficientlyfor microphone amplifier.

Push Button Type Speaker Selector
Two pair of speaker terminals, i.e. A and B may be changed by push-button correctly locked. With A and B pushed at the same time, simultaneous activation is allowed.

One Touch Type Speaker Terminals
Speaker terminals are of one touch connection type which allow easy and correct coupling, so that the system will eliminate any trouble on speaker connection.

Loudness Control
On a level of -30 dB, low pass is 100 Hz with +8db and high pass in 10 kHz with +3 dB, both provided higher than the conventional, so that the control will supplement low and high pitched tones.
Continuous Power Output: 
Both channel driven: 
40/40 watts  into 8 Ω at any frequency from 20 - 20,000 Hz
43/43 watts into 8 Ω at 1,000 Hz
57/57 watts into 4 Ω at 1,000 Hz
Each channel driven:
55/55 watts into 8 Ω at 1,000 Hz
70/70 watts into 4 Ω at 1,000 Hz
Dynamic Power Output (IHF): 
130 watts per channel into 8 Ω at 1,000 Hz
220 watts per channel into 4 Ω at 1,000 Hz
Total Harmonic Distortion: 
less than 0,5% at rated output from 20 - 20,000 Hz;
less than 0,05% at -3 dB rated output
Intermodulation Distortion (60 Hz; 7,000 Hz; 4:1): 
less than 0.3% at rated output;
less than 0,05% at -3 dB rated output
Power Bandwidth (IHF):  10 Hz to 50,000 Hz
Input Sensitivity/Impedance (for rated output, at 1,000 Hz):
Phono 1:  2,5 mV/50 kΩ
Phono 2:  2,5 mV/ 50 kΩ
Tuner:  200 mV/ 100 kΩ
Aux 1, 2:  200 mV/ 100 kΩ
Tape Play A & B:  200 mV/ 100 kΩ
Mic: 3 mV/50 k Ω
Main Amp. Input:  1 V/ 50 kΩ
Recording Output (below rated input):
Tape Rec A & B:  200 mV
DIN connector:  40 mV
Signal-to-Noise Ratio (below rated output): 
Phono 1 & 2:  68 dB
Mic: 70 dB
Tuner:  75 dB
Aux 1 & 2:  75 dB
Tape Play A & B:  75 dB
Noise at Minimum Volume Control:  0,3 mV at 8 Ω, 0,000012 milli watts
Damping Factor:  32 at 8 Ω load; 64 at 16 Ω load
Speaker Impedance:  accepts  4  to 16 Ω
Bass Control:  ±10 dB at 100 Hz (with 2 dB step switch)
Treble Control:  ±10 dB at 10,000 Hz (with 2 dB step switch)
Low Filter:  40 Hz and 80 Hz cut off, 12 dB per octave
High Filter:  7,000 Hz cut off, 6 dB  per octave
Loudness Control (-30 dB):  +8 dB at 100 Hz; +3 dB at 10,000 Hz
Speaker :  A, B (ON-OFF at push switch)
Selector :  Aux1, Aux 2, Tuner, phono 1, Phono 2, Mic
Mode :  left, Right, Stereo, REV, Mix
Tape Monitor :  Dubbing, (A→B), A Play, Source< B Play, Dubbing (B→A)
Others :  Low & High Filter, Loudness, Muting, Power
AC Outlets:  1 switched & 3 unswitched
Power Requirement:  110 - 120 V/220 - 240 V AC, 50/60 Hz
Power Consumption:  235 watts at full power; 15 watts at no signal
Dimensions (W x H x D):  435 x 153 x 300 mm (17-1/8 x 6-1/32 x 11-13/16 inch)

Weight:  11,5 kg (25,4 lbs)

Kenwood KA-4000

 Kenwood 120 Watt Solid State Amplifier Model KA-4000
120 watts of IHF standard total music power enough to drive even low efficiency Hi-Fi speaker
The wide power bandwidth of 13 Hz to 30,000 Hz with very low IM distortion
Lever type -20 dB muting switch of quick response for momentary quietness during telephone call, etc.
2 dv step type tone controls
Blue light indicators for input selector switch
Lever type high and low filter switches
Pre-amplifier outputs for use with other power amplifier or multichannel system.
Main amplifier inputs for the use with pther pre-amplifier, tuner and tape recorder with pre-amplifier, and also these inputs enable you to drive the main amplifier directly
Speakers terminals for 2 sets of stereo speakers and front panel speaker selector switch (A, B, A & B and Phones)
Large Volume/Balance controls knob located in center of front panel.
Exclusive blow-out proof automatic circuit breaker protects power transistors

Power Output (continous power; at any frequency from 20 -20,000 Hz):
Total Music Power (IHF):  120 watts at 4 Ω;  100 watts at 8 Ω load
Continuous Power:
Each channel driven:  53/53 watts at 4 ohms load;  40/40 watts at 8 ohms load.
Both channels driven;  41/41 watts at  4 ohms load;  32/32 watts at 8 ohms load.
Power bandwidth (IHF):  13 Hz to 30,000 Hz
Harmonic Distortion:  Less than 0,5% at rated output from 20 to 20,000 Hz
Intermodulation Distortion (60 Hz & 7,000 Hz, 4:1): 
Less than 0,3% at rated output or at any level of less than rated output;
Less than 0,1% at -3 dB rated output
Frequency Response:
Main Amp. only;  18 Hz to 50,000 Hz ±1 dB
High Level Input;  20 Hz to 50,000 Hz ±1 dB
Sensitivity (fro rated output at 8 ohms load):
Phono 1;  2 mV
Phono 2:  2 mV
Tape Head:  2,3 mV
MIC: 2 mV
AUX:  200 mV
Tuner:  200 mV
Tape Play:  200 mV
Main Amp Input:  100 mV
Input Impedance (at 1,000 Hz):
Phono 1 :  50 Kohms
Phono 2 :  50 Kohms
Tape Head :  100 Kohms
MIC :  100 Kohms
AUX,Tuner,Tape Play :  100 dB
Main Amp. Input :  300 kohms
Signal-to-Noise Ratio (below rated output):
Phono 1 :  65 dB
Phono 2 :  65 dB
Tape Head :  63 dB
MIC :  67 dB
AUX, Tuner, Tape Play :  77 db
Noise at minimum volume control: 1mV at 8 ohms or 0,0125 milliwatts.
Output Impedance (at speaker terminal):
0,29 ohm at 1,000 Hz
0,52 ohm at 50 Hz
0,29 ohm at 10,000 Hz
Damping Factor (at 1,000 Hz):
55 at 16 ohms load
27,5 at 8 ohms load
Low Filter (for rumble):  80 Hz Cutoff, 12 dB per Octave
High Filter (for scratch ):  8,000 Hz Cutoff, 12 dB per octave
Bass control:  ±10 dB at 1000 Hz with 2 dB step switch
Treble Control;  ±10 at 10,000 Hz with 2 dB stepswitch
Power Requirement/Consumption:
AC 110-120/220-230 volts, 50/60 Hz
18 watts quiescent. 190 watts at full power
Dimensions:  16⁵/₁₆"  x  5 ⁵/₃₂"  x  11 ¹/₃₂" (W x H x D)

Weight: 17,6 lbs

Yamaha TC-520

 Yamaha TC-520 Front-loading  Two head Stereo Cassette Tape Deck
Mechanical Tape Loading
Chrome Tape Capability
3-digit Mechanical Counter
Two analog VU meters
Bias Fine Tune
Dolby B circuit
 The wrong cassette deck will play your tapes to death. Just a fractional misalignment of all those pulleys, belts and wheels, and you wind up with tapes that are more of a pain than a pleasure to listen to. That's why we took such care with the tape transport in our new TC-520.
The only directly power driven part, for instance, is the capstan. So there's less chance your tapes will feel stretched.
We've made sure that this crucial capstan is rounded to within 0,1 microns of perfection. So everything turns the smoothest possible circle. There's double belt drive for even more stable rotation.
While the DC motor is designed to give high torque and low vibration. Very smooth.
Just as smooth as all the other features.
Yamaha's superhard permalloy head means clean sound with less wear. You have the choice of low noise, chrome and ferrichrome positions. A bias adjust selector means you can choose the perfecct setting for each individual tape. While two illuminated VU's flash red for +8 dB, yellow for +3 dB.
Yamaha high performance means you can always expect pur natural sound with low distortion. So you'll never hear anything except what you want to hear on our new TC-520.
Type:  2-head, single cassette deck
Track System: 4-track, 2-stereo channel
Tape Speed:  4,8 cm/s
Motor: Electronic Controled DC Motor
Frequency Response:
Normal Tape :  30 - 13,000 Hz ±3 dB
Ferrichrome, Chrome Tape :  30 - 15,000 Hz ±3 dB
Normal Tape :  less than 1,5%
Ferrichrome, Chrome Tape :  less than 2,0%
Wow and Flutter:  less than 0,05%
Signal-to-Noise Ratio:  57 dB (with Dolby  at 66 dB)
Inputs Line/Mic:  50 mV / 0,3 mV
Output Line:  0,4 V
Dimensions (W x H x D):  435 x 160 x 327 (17,1" x 6,3" x 12.9")
Weight:  7,5 kg (16 lb 52 oz)

Yamaha CDX-390

ENTRY LEVEL SINGLE DISC COMPACT DISC PLAYER - Provides high quality CD performance and convenience features.
TAPE EDIT - Automatically arranges CD selections to most efficiently use selected tape recording length.
CD SYNCHRO START - Works with Yamaha cassette deck to provide completely synchronized CD and tape start at the touch of a button.
PEAK SEARCH - Searches for the highest output level, so the optimum recording level can be easily set.
DIRECT TRACK ACCESS - Front panel 10-key pad allows easy selection of particular tracks.
4-MODE TIME DISPLAY - Visually check total time on disc, total remaining time, elapsed track time, elapsed total time.
INTELLIGENT DIGITAL SERVO - Adjusts tracking, focus, and motor speed to compensate for disc defects, warpage, and dust.
SINGLE BIT DAC - Delivers excellent digital-to-analog conversion.

Total Harmonic Distortion:  0,003%
Frequency Response:  2 Hz - 20,000 Hz ±0,5 dB
Signal-to-Noise Ratio:  105 dB
Dynamic Range:  95 dB
Wow and Flutter:  Unmeasurable
Output Voltage (1 kHz, 0 dB):  2,0 ±0,5 V
Power Requirements:  110/120/220/240 V, 50/60 Hz
Power Consumption:  20 W
Dimensions (W x H x D)435 x 96 x 272 mm  (17-1/8" x  3-3/4" x 10-3/4")

Weight3.8 kg  (8.4 lbs.)

Tannoy Arden

This system is a highly developed and refined version of the Tannoy loudspeaker. It utilises the dual concentric principle to provide an integrated sound source which, over the past quarter of a century, has become an established quality reference in recording, broadcasting and television studios.
The Tannoy system combines a precision built high frequency compression horn driver with a direct radiator bass unit embodying the unique Girdacoustic ( on HDP385A and HDP315A only) reinforced cone.
These two drivers are mounted concentrically on a single frame and magnet assembly. They are driven  through a sophisticated separate crossover network creating a system covering the entire frequency range from 20 Hz to 20 kHz.
Distortion products are negligible, and the wide, smooth frequency range with excellent transient response result in very natural reproduction and an almost total lack of colouration.
Sensitivity is high. A 20 Watt amplifier used with the smaller systems is more than adequate for normal domestic purposes. This sensitivity combined with high power handling capacity, makes the larger units ideal for the most sophisticated professional or home installations.
The outstanding performance characteristics of the HPD385A Integrated Loudspeaker System are completely realised by the Arden, the largest model in the range. An extended bass response is obtained through the use of a triple ducted port system resulting in very low distortion products. The system is front recess mounted to avoid tunnel and diffraction effects. With generous internal strutting for high rigidity, the internal cavity is critically damped with graded acoustic foam ensuring lack of colouration in the bass response.
A - Rolled surround for stability in low bass response
B - Unique ribbing virtually eliminates cone break-up ensuring smooth response and extraordinarily high power capacity
C- High temperature voice coil
D - Dustproof, acoustically transparent sealing dome
E - Concentric HF horn (completed by curved LF cone)
F - Phase compensating multiple throat for extended and smooth HF response
G - Acoustic balance cavity for reduced distortion
H - Precision contoured high frequency diaphragm
I - Aluminium voice coil conductor for superb HF response
J - Exclusive magnetic shunt for increased LF flux
 The Crossover Network
The Tannoy crossover network divides the electrical energy from the amplifier between the high frequency compression driver and the low frequency direct radiator and makes a vital contribution to the overall performance of the system.
It incorporates two controls. One permits attenuation of the treble energy output only in the range above 5 kHz. The other allows the output of the high frequency unit to be increased or attenuated over its entire range from 1 kHz to 20 kHz, compensating for roomacoustics and individual preference.
The crossover is assembled to the very highest standards on a fibreglass printed circuit board. Solid dielectric capacitors are used throughout and all resistors and inductors are very generously rated.
The design of the crossover ensures that the complete loudspeaker system has an excellent impedance characteristic which provides the ideal load for any amplifier.
Integrated Drive System
The Tannoy Integrated Drive System consists of a direct  radiator bass unit and a high frequency horn-loaded compression driver both located concentrically within the same frame and magnet assembly, this is why it is known as the dual concentric system.
Bass Unit
This is a low resonance speaker with a 2" high temperature voice coil. The unique Girdacoustic reinforced cone ensures true piston action and smooth performance extending well into the midrange region.
Treble Unit
High frequencies are reproduced by a horn-loaded compression driver utilizzing a duralumin diaphragm and a 2" diameter aluminium voice coil.
Low Frequency Direct Radiator
Maximum Diameter:  420 mm (16 ½")
Voice Coil Diameter:  50 mm (2")
Bl Factor in gauss/cm:  20 x 10⁶
Fundamental Resonance:  20 Hz
High Frequency Compression Driver
Duralumin Diaphragm:  50 mm (2")
Voice Coil  Diameter:  50 mm (2")
Horn Cut-off Frequency:  500 Hz
Drive System:  3828
Power Handling Capacity:  85 W
Nominal Impedance: 8 ohms
Frequency Response:  30 Hz - 20 kHz, ±4 dB
Sensitivity; Input Watts produce 96 dB at 1 m:  3
Crossover Frequency:  1 kHz
System Dimensions (H x W x D):  990 x 660 x 370 mm (39" x 26" x 14 ½"

Weight:  56 kg (shipping)

Tannoy Berkeley

This system provides the high power handling capacity and sensitivity of the HPD385A unit in a compact enclosure where insufficient space is available to accommodate the Arden.
A carefully designed dual ducted port reovides optimum bass characteristics in relation to enclosure volume, and the loudspeaker is front recess mounted to ensure unimpeded treble response. High desnsity stock is used throughout the cabinet construction and massive internal reinforcement renders the structure free from spurious resonances. Each section of the two-part grille can be removed separately to facilitate treble adjustment.
Integrated Drive System
The Tannoy Integrated Drive System consists of a direct  radiator bass unit and a high frequency horn-loaded compression driver both located concentrically within the same frame and magnet assembly, this is why it is known as the dual concentric system.
Bass Unit
This is a low resonance speaker with a 2" high temperature voice coil. The unique Girdacoustic reinforced cone ensures true piston action and smooth performance extending well into the midrange region.
Treble Unit
High frequencies are reproduced by a horn-loaded compression driver utilizzing a duralumin diaphragm and a 2" diameter aluminium voice coil.

Crossover Network
The crossover network receives the electrical energy fromm the amplifier and divides it between thr high frequency compression driver and the low frequency bass driver and makes a vital contribution to the overall performance of the system.
Tannoy crossover networks are of the highest quality; capacitors are non-polarized, solid dielectric types for low lossles and close tolerances; resistors and inductors are very generously rated; and all components are assembled on a fibreglass printed circuit board for maximum reliability.
 System adjustment
The Tannoy system is provided with two controls located on the front baffle. These are labelled "Roll-off" and "Energy". They can be used to compensate for the acoustic characteristics of the listening room and should be adjusted with the amplifier controls in the flat or uncompensated position. Each loudspeaker system should be adjusted individually. This is mot easily done by rotating the amplifier Balance control to select the desired loudspeaker.
The Energy control has five positions and enables the output of the high frequency driver to be increased or decreased over its entire range from 1 kHz to 20 kHz. The Roll-off control affects only the extreme high frequencies, i.e. those above 5 kHz.
The flattest response will be obtained with both controls set at the "Level" position, which should be used for initial listening tests.  If the overall high frequency sound quality seems too prominent, the -1 or -2 positions for the Energy control should be tried. If the sound is subdued +1 or +2 will be preferred. Once the Energy setting has been established the Roll-off control can be adjusted to reduce extreme high frequency content if necessary.

Tannoy enclosures are solidly constructed from high density particle board and are lined with acoustic foam to absorb reflections and eliminate standing waves and bitumen to damp mechanical resonance. The exposed natural woodgrain surfaces of each enclosure are of American Walnut veneers. The cabinets are carefully handrubbed with oil and wax, which enhances the richness of the wood and affords excellent protection. Both the Arden and the Berkeley are braced internally to reduce spurious resonances which can occur in large panel areas, and ported to provide low frequency loading, thereby reducing distortion and extending bass response.
Low Frequency Direct Radiator
Maximum Diameter:  420 mm (16 ½")
Voice Coil Diameter:  50 mm (2")
Bl Factor in gauss/cm:  20 x 10⁶
Fundamental Resonance:  20 Hz
High Frequency Compression Driver
Duralumin Diaphragm:  50 mm (2")
Voice Coil  Diameter:  50 mm (2")
Horn Cut-off Frequency:  500 Hz
Drive System:  3828
Power Handling Capacity:  85 W
Nominal Impedance: 8 ohms
Frequency Response:  35 Hz - 20 kHz, ±4 dB
Sensitivity; Input Watts produce 96 dB at 1 m:  3
Crossover Frequency:  1 kHz
System Dimensions (H x W x D):  840 x 540 x 310 mm (33" x 21" x 12")

Weight:  41 kg (shipping)