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





McIntosh MR 73

 The McIntosh MR 73 is a precision engineered, highly sensitive solid state AM/FM tuner.
The research staff of mcIntosh Laboratory, using the latest technology in solid state physics, has developed many circuit advances:
Phase linear crystal shaped IF amplifiers
Integrated Circuits that are the equivalent of 16 transistors, 3 zener diodes, 5 diodes and 23 resistors
Special multiplex (stereo) detecting circuits that eliminate critical adjustments
Ultrasonic muting for complete silence between stations while tuning.
Automatic stereo-mono switching that is "clickless" and completely electronic.
Visual multipath indicator to help avoid multipath distortion showing as a visual indicator of correct antenna direction for minimum multipath reception
New D'Aarsonval movement meters of increased sensitivity which do not need zero setting adjustments.
A new computer designed filter to reduce noise from stations broadcasting subcarrier auxiliary music services. No other tuner uses such a filter.

Exclusive McIntosh PANLOC is used for installation.The PANLOC system gives you absolute ease of installation, operation and maintenance.
PANLOC is the first professional installation technique to be used on stereo instruments.  In the PANLOC system a metal shelf is mounted first. The tuner slides into position on this shelf. Depressing the front panel PANLOC buttons, locks the tuner firmly into position against the mouting panel.
Onec you have enjoyed the outstanding performance of the Mr 73, you will understand why McIntosh products have earned their reputation as "the best". Your McIntosh MR 73 tuner will give you years of the finest possible reception, and will be a valued part of your home music system.
 FM SECTION
This is divided into two separate modular sections:
1 - The 100 mHz Radio Frequency (RF) Section
2 - The FM-IF and Detector Section
The first section houses the complete FM-RF front-end part of the AM_RF circuits. A special four section, variable tuning capacitor provides a high degree of RF selectivity and excellent spurious response rejection. The problem of image rejection has been greatly reduced in the Rf section of the MR 73.
The two stage parallel-fed-cascode  junction field effect transistor (JFET) RF amplifier gives better sensitivity and higher gain  than conventional one-stage amplifiers. The use of JFET's helps to further reduce the problem of front end overload in strong signal areas.
A mixer using a JFET has been designed for high sensitivity and freedom from overload. Low temperature coefficient components have been designed into the FM local oscillator to revent frequency drift. The frequency stability inherent in the local oscillator makes automatic  frequency control (AFC) unnecessary. The rate of drift of the local oscillator is less than ten parts per million per degree cantigrade.
Both the FM and AM-RF front ends have been designed in the same completely encased metal modules. This design gives protection against radiation or interference. The RF circuits of the MR 73 exceed the FCC requirements for suppression of oscillator radiation.
The MR 73 has antenna  connections for either 300 Ω twin lead transmission line or 75 Ω coaxial cable. The normal input impedance of the first RF amplifier is 75 ohms. Impedance match to 300 Ω is provided by a McIntosh designed balun transformer which has negligible losses. Connections for a 300 Ω line are made with new push type terminals. No tools are required. A type F male linear phase characteristics of the IF amplifier.
 The FM-IF and Detector  section design required extended engineering time and testing and uses the latest concepts in integrated circuits and crystal filters. The FM-IF consist of two integrated circuits and two phase linear crystal filters. They combine to give a total gain of over 120 dB (the signal is amplified to over 1,000,000 times its original level). The response curve has a nearly flat top with linear phase characteristics. The skirts of the response curve are very steep. The maximum width is 240 kHz at -3 dB and 400 kHz at -60 dB. The response curve is symmetrical each side of the center frequency. The crystal filters are permanently sealed and do not require adjusting. The IF cannot drift nor vibrate out of adjustment.
Each of the two integrated circuits used in the FM-IF of the MR 73 contain 16 transistors, 3 zenar diodes, 5 diodes and 23 resistors, all on a single monolithic silicon chip.
The exceptionally high gain of the two integrated circuits assumes "hard limiting" at very low levels of input signals.
A "phase" or "Foster Seeley" discriminator has been designed to complement the integrated circuit IF section. The IF section has  exceptionally high gain and hard limiting characteristics, yet the capture ratio is quite low. The detected output signal of the discriminator is extremely low in distortion content.
De-emphasis of the discriminator output restores the frequency amplitude characteristics o the same level they were before transmission.
 C.FM Stereo Multiplex Section
McIntosh laboratory has developed a special detecting circuit in the multiplex section.
A  particular advantage of this circuit in the elimination of the critical adjustments necessary with commonly used matrixing circuits. The circuit detects the L-R sidebands, then automatically matrixes the recovered information with the L+R main carrier signal. This yields the left and right program output with maximum separation.
The 19 kHz pilot signal is filtered from the composite stereo input signal, amplified by a special limiting amplifier, doubled to the 38 kHz carrier sognal. The  new combination of signals is fed to the special detector circuit mentioned above. Balanced full wave detectors are used to cancel the 38 kHz conponents in the output.
The SCA (Subsidiary Communication Authorization) signal must be removed from the composite output. This is accomplished by the use of a new "Image Parameter" band elimination filter that has  been computer designed. The SCA filter rejects SCA signals without impairing stereo performance.
FM muting in the McIntosh MR 73 operates by detecting ultra-sonic noise which is present when tuning between stations or when receiving a weak station. The muting circuit can be activated or defeated by the use of the muting switch on the front panel. The level of muting desired can be adjusted by the muting level control on the top panel. Varying the muting control adjusts the threshold at which the muting takes effect.
When the 19 kHz carrier of a stereo signal is received, the automatic FM stsreo switching circuit activates the multiplex decoding circuit. This lights the stereo indicator. The circuit switching is all done electronically with no clicks. The automatic stereo switching can be defeated by turning the mode selector switch to FM Mono (In this position the stereo indicator will still light to indicate the presence of a stereo signal). On monophonic  transmissions the stereo switching is inactive at all times, assuring a greater signal to noise ratio. The stereo switching circuit has been designed so that noise will not activate it.
 AM SECTION
The "State-of-the-art." in electronic technology has been incorporated by McIntosh into the MR 73 with the use of metal oxide silicon field effect transistors (MOSFET's) in the AM section.  An AM-RF amplifier circuit includes a three section variable tuning capacitor in the metal enclosed shielded module, which also houses the FM-RF front end.  The Am-RF amplifier uses a dual-insulated gate MOSFET to obtain more overload protection against strong local stations than can be obtained with conventional bipolar transistors.
The AM-RF mixer is also a dual-insulated gate MOSFET. The use of MOSFET's in the RF amplifier and mixer provides the MR 73 with very little cross modulation (spurious response) and the image rejection is very good.
Three double tuned IF transformers are used to obtain a high degree of selectivity yet still allow good Amfidelity. A 10 kHz whistle filter has been incorporated at the output of the AM detector.  Its  purpose is to supress hetrodyning that occurs between adjacent AM carriers.
To increase the "pulling power" of the AM section of the MR 73, connect an external antenna at the rear apron of the unit by using a push connector. An internal transformer matches the external antenna to the input impedance of the AM front end. An optional highly sensitive loop stick antenna is also provided for local or strong stations. A switch on the back panel selects either loopstick or external antenna.
An AM sensitivity switch has been provided to decrease both the gain of the RF amplifier and the noise between stations.
 Audio Preamplifier Section
An audio amplifier has been incorporated in the McIntosh MR 73. It in creases the audio level from the AM or FM multiplex outputs to a level sufficient to drive a preamplifier or other accessory equipment. The audio amplifier consists of 2 separate amplifiers, each amplifier having three transistors. The design uses considerable negative feedback. Negative feedback helps to achieve low distortion, wide frequency response, and unexcelled stability. Each audio amplifier has two low impedance outputs. One is a fixed output set at 2,5 volts. The second output is variable by the volume the control on the front panel.
By cross-coupling a small portion of one channel into the other in the audio amplifier, the residual alternate channel information can be cancelled, thereby further increasing the stero channel separation.
Also included in the audio section is a Stereo Filter switch. With the Stereo Filter turned on and waek stations are being received, stereo noise is reduced, but still allows ample stereo listening performance.

Power Supply
Special design attention has been given to the power supply section of the McIntosh MR 73. Two separate rectifier circuits are used in the MR 73.
The 16 volt regulator is the power heart of teh Mr 73. All signal stages throughout the unit are powered from this regulator. The 16 volt regulator is very elaborate in design, using a specially selected transistor and associated circuit. The regulator uses electronic filtering to insure the lowest possible background hum level, maximum stability and extremely good regulation.
A half wave rectifier and filter, supply the DC high voltage needed for the anode of the multipath indicator. The second power supply is a full wave rectifier which supplies DC to the multiplex indicator and to the voltage regulator.
Specifications
FM Section
Frequency: 88 to 108 MHz
Useable Sensitivity:  2,5 microvolts at 100% modulation (±75 kHz deviation) for less than 3% total noise and harmonic distortion in accordance with IHF standards
Audio Frequency Response:  Flat from 20 Hz to 20 kHz with standard de-emphasis and 19 kHz pilot filter.
Harmonic Distortion:
Mono : Less than 0,3% at 100% modulation ±75 kHz deviation.
Stereo : les than 0,7%
Capture Ratio:  Better than 1,5% dB at 100% modulation
Muting:  AF injected ultrasonic muting at least 60 dB noise reduction between stations
Oscillator Drift:  less than 25 kHz
Image Rejection:  Better than 80 dB at 90 MHz;  better than 70 dB at 100 MHz
Hum: better than 70 dB below 100% modulation
Output:  Approx. 2,5 volts, low impedance
FM Antenna Inputs:  Built-in loopstick or external antenna switch selected
IF:  two Ics and two phase linear crystan filters
Radiation: Substantially below FCC requirements
Stereo Separtion:  Better than 35 dB at 1 kHz
Stereo Filter: Greater than 48 dB suppression of 38 kHz multiplex carrier
Stereo Indicator:  Front panel multiplex stereo light activated by 19 kHz carrier-only
SCA Filter:  50 dB down at 67 kHz to 74 kHz , 275 dB per octave slope
Automatic Mono/Stereo Switch:  McIntosh developed; all electronic automatic mono/stereo switching circuit
Semiconductor Complement:  22 diode, 24 Transistors, 2 Integrated Circuits, 1 Indicator Tube

AM Section
Frequency:  55 to 160 kHz
Sensitivity: Better than 12 microvolts at 1000 kHz (using the external antenna input)
Frequency Response:  Down 6 dB at 5 kHz
Harmonic Distortion:  less than 1% at 39 % modulation
Selectivity:  -3 dB at 10 kHz
Image Rejection:   60 dB or greater at 1000 kHz
Signal-to-noise Ratio Better than 55 dB

General
Power Consumption:  20 watts, 105 to 125 volts, 50 to 60 Hz
Dimensions
Front Panel : 16 inches wide by 5-7/16inches high
Chassis : 15 inches wide by 13 inches deep, including PANLOC shelf and back panel connectors
Knob Clearance : 1-½ inches in front of mouting panel
Weight:  24 pounds net, 36 pounds in shipping carton
Finish:  Front panel. Anodized gold and black with special gold/teal panel nomenclature illumination.
Chassis:  Chrome and black

Mouting:  McIntosh  developed professional PANLOCK

Marantz 1060

 The Marantz 1060 has many qualities.
For example, you can connect to almost any type of speakers, large.
His power is sufficient to dominate the bustle of the noisiest nights.
The sound quality is perfect at both ends of the audible spectrum. The filter "High" eliminates surface noise disks, tapes breath.
The "Low" filter removes background noise interference.
You can easily select one of six listening sources.
Other benefits.
Sockets for two tape recorders and sockets for stereo microphone on the front panel.
The particularly nice thing about the Marantz 1060 is that it will go with just about any sized speaker system and still put out enough power to cover a room full of people. 60 Watts of power. And more like 90 Watts under typical listening conditions. At full volume or low level the distortion stays about the same. Or perhaps we should say "lack of Distortion". The Model 1060 has less than 0,5% total harmonic and intermodulation distortion. Typically 0,1%. Perhaps that's why it's received rave reviews in audio publications throughout the world. And perhaps that's why so many have been sold. It's features, also, place it among the very finest. There's a high filter to eliminate record scratch and tape hiss. And a low filter to cut hum and rumble. Other features include inputs for two tape recorders, as well as front panel stereo microphone input jacks. The list goes on. But for the 1060 listening is believing. You can do both.
Specifications

Gain-Phono (low level) to pre-amp output:  55 dB
Phono to recording output:  40 dB
High level to pre-amp output:  15 dB
Input Impedance (Low level input):
Phono : 47 k Ω
Microphone : 47 k Ω
High level Input:  100 k Ω
Phono Input Sensitivity (Low):  1.8 mV to equal 1 Volt output at pre-amp out
Rgequency Response:  20 Hz to 20 kHz ±1 dB at rated output
Intermodulation Distortion:  less than 0,5% at rated power output from 20 Hz to 20 kHz with both channel driven (SMPTE)
Total Harmonic Distortion:  Less than 0,5% at rated power output from 20 Hz to 20 kHz with both channel driven
Damping Factor (20 Hz to 20 kHz):  Greater than 45 into 8 Ω load
Total Noise (From magnetic phono input to power amp output):  Less than 1,5 µV equivalent input at rated output into 8 Ω
Volume Tracking:  Within 3 dB
Comparable Total Music Power (IHF):  90 Watts at 8 Ω
Rated Continuous (RMS) Output (per channel, both channels operating simultaneously): 
30 Watts at 4 and 8 Ω
20 Watts at 16 Ω
Power Requirement:  AC 100/120/200/220/240 V, 50/60 Hz
At Rated output both channels operating:  190 Watts
Idling Power (volume control at zero):  48 Watts
Dimensions (W x H x D):  14-11/64 x 4-23/32 x 11-1/32 inches
Weight:  18 lbs net

Thorens TD 318

 The TD 318 is the logical conclusion of the realisation of the experience that Thorens have made with the development of the world acknowledged "Reference" and "Prestige" turntables, combined with more than 100 years of tradition in the reproduction of music. The Thorens TD 318 - a concept with future.
Features:
Servo controlled electronic Thorens belt driverESONANCE ABSORBING mdf CHASSIS
Clean and uncoloured sound
Design of lasting elegance
Sound improving platter mat
Easily adjustable suspension

Spring-loaded lid hinge
 The Thorens belt-drive
The Thorens-motor drives the turntable platter by means of a rubber belt. The natural elasticity of the belt prevents most motor vibrations from reaching the plater and, therefore, the pick-up stylus. In more than 20 years of continuous development, Thorens has reduced the very few disadvantages of belt drive to an absolute minimum and has brought it to a level of technical perfection which is not approached by any other system known today. A particular development is the Thorens acceleration clutch, which prevents the belt from stretching, thus reducing the starting time and eliminating chassis vibration.
Because of the high performance required by desceming listeners, Thorens has decided to retain its own unique belt drive system as long no better drive system is developed in Thorens laboratories or elsewhere.
 The Thorens Floating Suspension
Every turntable must be damped by a suspension system to prevent the sensitive pick-up from enviromental vibration and from acoustic feedback. If the springs are placed between motor and turntable platter, they than fulfill the additional requirement of decoupling motor vibrations almost completely from the turntable and the pick-up system.
Chassis 1 carries the motor and controls. Chassis 2 which is isolated by three easily adjustable leaf springs carries the platter and tone arm. The chassis of the 318 is made of amedite material which absorbs resonances resulting in cleaner and more precise sound.
Specifications mean very little to how good a turntable sounds. The selection of the appropriate materials, the individual tuning, and the harmonisation of all the components are decisive in determining the sound quality.
Thorens have been involved in the production of turntables since the existance of records.


Specifications TD 318
Drive System:  1 speed belt drive
Motor:  Low voltage 16 pole synchronous motor, with slip cloutch for instantaneous start.
Speeds:  33 and 45 RPM, electronic speed selection
Motor Speed Control:  2 phase generator for synchronous control
Turntable Platter:  2,7 kg zinc alloy, dynamically balanced
Platter Diameter:  300 mm (12")
Wow and Flutter (DIN 45507):  ≤ 0,04%
Rumble unweighted (DIN 45539):  > 50 dB
Rumble weighted (DIN 455539):  > 70 dB
Power Requirements:  17 V max. 140 mA
Mains Voltage:  may be connected to any line voltage and frequency using the appropiate Thorens AC adapter
Power Consumption:  5 Watt
Dimensions (W x H x D):  440 x 170 x 350 mm (cover closed)
Height with cover open:  430 mm

Weight:  10,5 kg

Thorens TP 21

 THORENS TP 21 Tone arm
For optimum in tracking ability it is not sufficient that a tone arm has a low bearing friction. It is much more important that it has a low effective mass, because high mass prevents the stylus from following the imperfections (warp or ripple) of the record as it should do.
To overcome hgh effective mass one can increase the stylus force, but this results in excessive record wear. 
  
In addition, the TP 21 is a straight arm and not S-shaped. The necessary offset angle is independent of the arm shape. A special surface treatment of the tone arm tube absorbs all undesirable resonances of the tone arm.
It will optimise ideally with almost every cartridge.

Specifications TP 21 tone arm
Effective Length:  232 mm
Effective Mass:  12,5 g
Stylus Overhang:  16,4 mm adjustable
Offset single:  23°
Lateral Tracking Error:  ≤ 0,18°/cm of radius
Skating-compensation:  1 or 2 weights on nylon thread
Tracking Force:  Graduation scale on counterweight
Bearing Friction:  ≤ 0,20 mN  (20mp) in both planes
Cartridge Mounting:  Standard ½"

Capacitance of cable:  150 pF

Sony TC U30

 Sony TC U 30

Features
Sixteen segment LED record meters enable simple but precise adjustment of the record level.
Timer facility
FG servo motor
Three position tape selector for normal, ferrichrome and chromium dioxide tapes.
Soft  eject
Full auto shut off mechanism
Input selector for microphone and line.
Stereo headphone jack socket.
Pause button.


Specifications:
Wow and Flutter:  0,05% wrms, ±0,14% DIN
Signal-to-Noise Ratio:  56 dB (FeCr)
Frequency Response:  50 - 13,000 Hz (±3 dB) FeCr
Total Harmonic Distortion:  1,7% with FeCr tape
InputsSensitivity/Impedance:
Mic. : -70 dB (0,25 mV) / Low
Line : -20 dB (77,5 mV) /100 kohms
Input DIN Impedance: 10 kohms
Outputs Level / Impedance
Line : 435 mV/ more than 10 kohms
Output DIN Impedance: 50 kohms
Output Headphones Impedance:  8 ohms
Motor:  Tri Duty FG servo motor
Heads:  1 x F&F rec/PB head;  1 x erase head
Power Requirements:  AC 240 V, 50 Hz
Power Consumption:  16 watts
Dimensions (W x H x D):  430 x 130 x 290 mm

Weight:  5,4 kg

Sony TC U2

 Sony TC U2 Stereo Cassette Deck

Features:
Dolby noise reduction system to reduce hiss when recording or playing back tapes
Illuminated VU meters
FG servo motor
Three position tape selector for normal, ferrichrome and chromium dioxide tapes.
Soft  eject
Auto shut-off mechanism
Stereo headphone socket.


Specifications:
Wow and Flutter:  0,08% wrms, ±0,2% DIN
Signal-to-Noise Ratio:  55 dB (FeCr)
Frequency Response:  50 - 13,000 Hz (±3 dB) FeCr
Total Harmonic Distortion:  2% with FeCr tape
InputsSensitivity/Impedance:
Mic. : -70 dB (0,25 mV) / Low
Line : -20 dB (77,5 mV) /100 kohms
Input DIN Impedance: 10 kohms
Outputs Level / Impedance
Line : 435 mV/ more than 10 kohms
DIN : 435 mV/50 kohms
Output Headphones Impedance:  8 ohms
Motor:  FG servo motor
Heads:  1 x rec/PB head;  1 x erase head
Power Requirements:  AC 240 V, 50 Hz
Power Consumption:  12 watts
Dimensions (W x H x D):  145 x 410 x 260 mm

Weight:  5 kg

Yamaha CA-610

 Pure Power Boots Listening Pleasure
In the trend towards higher output powers, the CA-610 is unique. The minimum 40 Watts per channel is generous. With most home listening done between 1 and 10 Watts it can even be overwhelming. But the tremendous sense of scale, of unstrained ease in reproduction, and vast reserves of power, is more than you would expect from 40 Watts (and certainly more than you would get from most competitive amplifiers in the same class).
Capable of recapturing for you the thrill of an orchestral ‘tutt’ or a live rock concert the sound is never choked in noise or smeared with distortion at low levels.
From a mere 250 mW up to the full rated output of 40 Watts, and for all frequencies from 20 Hz to 20 kHz, the CA-610 gives no more than 0,05% THD. At 20 Watts output that drops to 0,01% (0,005% at 1 kHz) And signal-to-noise ratio is 75 dB for a 2.5 mV phono input. It all adds up to a new experience in impressive, powerful reproduction. The meters cover outputs from 0,01W to 100 W in one unswitched range a valuable feature that lets you know how much power your speakers are handling.
  Ultra Low Distortion Tone Control Circuitry.
The CA-610 tone controls offer the ideal combination of characteristics; simple to operate, they add virtually no distortion to the final sound. You can boost or cut treble and bass to suit your mood, your choice of music, or the acoustics of your room and speakers. And you can do it all without sacrificing quality for the convenience.
The special Yamaha negative feedback circuitry, and perfect crystal device trchnology used in the semiconductors, give smooth and precise control, with perfectly flat ‘0’ (zero) position. And so that you can compare the effects of your tone control settings, there are separate ‘defeat’ switches for bass and trebl, instantly bypassing the boost and cut circuits. Thespecial Yamaha design ensures that distortion is held to a minimum, typically contributing only 0,008% from 20 Hz to 20 kHz with 90 dB S/N ratio and 0,4 mV residual noise for the Aux terminals.
Music waveforms are incredibly complex, and the pulse plus sine wave response of the CA-610 shows how faithful reproduction of such signals is.

Clearly Audible Advance in Quality
The CA-610 is more than the sum of its parts. More than a combination of superb equalizer amplifier for record reproduction, sophisticated tone controls, and a powerful main amplifier. It’s truly integrated. And not only is power high, the distortion hits new lows at all listening levels form the quietest to the very loudest.

A Fantastic Range of Operating
The Ca-610 combines full tape monitoring and dubbing facilities with a new ability. Now, not only can you copy direct from one tape deck to another in any direction, and monitor recordings while they are being made  (if you have a three-head tape deck), You can also listen to any program source while you are recording. This lets you save time by dubbing at double speed, while relaxing to the sound of your favorite record. Or your can record an FM program for later audition while listening to a pre-recorded tape.
More Than an Amplifier  - A Complete Control Center
If you hear the Ca-610 you can hardly fail to want it. If you select it, you are sure to want the matching tuner; the CT-610. Together, they stand right at the top of their class, and from the nucleus of a first quality home stereo system.
The CA-610 has  a precision volume control, perfectly in balance within +_1 dB form 0 to -70 dB, with an attenuation curve that makes it easy to set the exact level you want. Then there is the -20 dB muting switch for an instant cut in volume. And the useful Rec Out Off position, cutting out the effect of tape decks when not recording. A host of useful features.

Advanced Equalizer Design
With its four-stage direct-coupled configuration, the equalizer resembles power amplifier design more than it does conventional circuitry. All four stages (differential current-mirror first stage plus emitter/ collector/ emitter-follower) operate under constant current bias, and give excellent open loop performance. The result is high stability and ultra-low distortion with moderate NFB for superb dynamic characteristics.

Sophisticated Amplifier Design

The combination of differential current-mirror first stage, and common emitter plus Darlington-connected fully symmetrical complementary output-capacitorless (OCL) output stage, with careful choice of high performance, low input capacity transistors in closely matched pairs, gives power amplifier performance virtually indistinguishable from Class A operation. Low frequency response is improved by separate power supplies for differential amp., pre-drive, and power stages, via two 6,800 uF smoothing capacitors.
Specifications
Continuous Min. RMS Power (both channels driven at rated distortion, 20Hz-20kHz):
50 + 50 Watts at 4 Ω
40 + 40 Watts at 8 Ω
Total harmonic Distortion:  0,05% or less (rated output)
Intermodulation Distortion:  0,05% or less (rated output)
Power bandwidth (IHF, both channels driven):  10 -50 ,000 Hz
Damping factor (8 Ω, 1 kHz):  better than 50
Output Terminals:  A, B or A + B (front panel switch)
Speaker Impedance:
A or B : 4 to 16 Ω
A + B : 8 to 16 Ω
Frequency response (Aux to Sp. Out):  20 Hz - 20,000 Hz  +0,2  -0,3 dB
RIAA Deviation: 20 Hz - 20,000 Hz ±0,3 dB
Signal-to-noise Ratio (IHF-A  network):
Aux to Sp. Out : 90 dB
Phono to Sp. Out : 75 dB
Residual Noise (Pre + Main Amp , 8 Ω):  0,4 mV
Input Sensitivity/Impedance:
Phono : 2,5 mV/50 k Ω
Tuner, Aux tape PB ( 1,2) : 150 mV/50 k Ω
Phono Dynamic Margin (1 kHz,0,1% THD) : 150 mV/1 k Ω
Output Level/Impedance:
Tape Rec Out (1, 2): 150 mV/1 k Ω
Tone Controls:
Bass : ± 12 dB boost/ cut at 50 Hz
Treble : ± 10 dB boost/ cut at 10 kHz
Loudness Control (volume -30 dB):  50 Hz : +9 dB, 10 kHz : +5 dB
Subsonic Filter:  -3 dB at 25 Hz (12 dB/oct)
Audio Muting:  -20 dB
Semiconductors:  4 Ics; 29 Transistors; 13 Diodes plus 3 Zener Diodes;
Power Source: 110/130/220/240 V AC switchable, 50/60 Hz
Power Consumption:  105 Watts
Dimensions (W x H x D):  435 x 150 x 298 mm (17" x 6" x 11¾")

Weight:  8 kg (17,6 lbs)

Arcam Delta 70

 The Arcam Delta 70 compact disc player has been designed to provide the best possible sound quality from compact disc digital audio. Together with the Arcam Delta 90, Delta 80 and the range of Arcam loudspeakers, the Delta 70 makes up the first complete CD based hi-fi system to be both designed and manufactured in great britain.
 Design Philosophy
Most specialist hi-fi companies merely "badge engineer" or modify mass produced Cd players, and are restricted to using their normal plastic chassis and standard circuit boards. From the outset, A&R Cambridge limited realised that this approach was simply not good enough to produce a Cd player to the standard demanded of an Arcam product. A&R therefore went to the trouble and expense of procuring full CD manufacturing licence. This gave our designers the opportunity to engineer the Delta 70 to a superior mechanical and electronic standard, incorporating much of the experience gained in producing some of the world's most acclaimed hi-fi amplifiers. Consequently, not only does the Delta 70 sound better, it is also visually more appealing and much easier to use than other CD players on the market.
 Versatility
Careful ergonomic design has simplified the operation of the Delta 70 to the extend that anyone can play a compact disc on it within a few seconds of first encountering the player. This is in marked contrast to many otherwise admirable CD players, whose complex control layout and over-elaborate displays frequently give rise to continued 'technofear', even amongst the most experienced users, let alone normal music lovers.
The controls on the front panel of the Delta 70 are divided into two groups. On the upper level they comprise just those needed to load, play and stop a compact disc. One the lower level we have included the pause button (conveniently located directly underneath the main stop button) and all the commonly needed programming functions. These include 3 speed search facilities and the previous and next track selection buttons, which will also access index points within a track. An easy to program memory is provided; this is capable of memorising the order of play of up to 20 different tracks.
To make operations even easier and more convenient the Delta 70 can be remote controlled using our optional infra-red remote control handset.
The displays on the Delta 70 have also been kept deliberately simple. An attractive and easy to read 4 digit fluorescent display provides readout of track and index numbers. It can also be used to indicate the total playing time of the disc and the elapsed time of each track as it is played.
Typical of the care and attention that our designers have taken is the location of the status indicator LEDs, which are provided for the power pause, and time/track functions. These are located just where they are needed, above the appropriate buttons, rather than buried elsewhere on the fascia.
Flexibility
The Delta 70's audio outputs are comprehensive, with both direct and variable outputs being provided. The latter is controlled via a low impedance ALPS potentiometer and is designed to feed a high quality power amplifier directly without the loss of quality associated with a conventional preamplifier. A headphones socket with adjustable output level is also included. This is driven from its own high quality amplifier, which has sufficient gain and power to drive almost any pair of moving coil headphones. Finally a digital output socket is fitted, for use with outboard D/A systems and for futur applictaions such as CD-ROM and CD-I.
 Electronic  Design
To recover as much information from the disc as possible the Delta 70 uses a swing arm single-beam laser pickup. This produces an inherently accurate signal from the disc than the 3-beam system used in most players. The disc playing mechanism is mounted on a fully floating sub-chassis to isolate it from external vibration. Allied to this is a 64K DRAM-based adaptive error correction system, which is one of the most comprehensive ever employed in a domestic Cd player. Taken together these features ensure the greatest possible integrity of recovered digital signal.
The digital signal is then processed using twin linear phase 120 element finite impulse response digital filters. These ultra stable low noise filters keep the audio band remerkably flat but dramatically attenuate the unwanted h.f. components of the audio signal. They are followed by dual 16 bit prcision DACs, operating in the classic four times oversampling mode at a frequency of 176,4 kHz. To enhance their timing linearity  (and hence sound quality) the Dacs are fed from a unique. A&R designed precision master oscillator.
Great care has been taken with all aspects of teh DAC and post-DAC filter and output circuitry to preserve this hard-won sound quality. Audiophile quality components been used throughout these stages, which have been assigned no less than five fully stabilised, critically decoupled power supplies. Integral withh the output filter which removes unwanted digital 'hash'. The circuitry is of an all-discrete transistor, direct coupled, class A design, which totally eliminates sound degrading interstage coupling capacitors from the signal path.
Specifications
Playback System:  16 bit , 4 x oversampling, dual DACs and class A direct coupled, discrete transistor analogue filter and output stages.
Optical Read-out System: 
Laser Type : Semiconductor Al Ga As
Numerical Aperture : 0,45
Wavelenght : 800 nm
Typical Audio performance (20 Hz - 20 kHz unless otherwise stated)
Frequency Response: 10 Hz - 10 kHz ±0,1 dB, -0,6 dB at 20 kHz
Channel Balance:  ±0,1 dB
Channel Phase balance ± 0,5 deg
THD:  0,007% at 1 kHz, 0 dB
Signal-to-Noise ratio:  101 dB unweighted; 105 dB CCIR/ARM weighted
Dynamic Range:  96 dB
Channel Separation:  100 dB at 1 kHz
Wow and Flutter:  Quartz precision control
Direct Outputs Level/Impedance:  2V RMS at MSB (0dB)/120 Ω
Miniumu Load Impedance:  5 k Ω
Variable Output Level/Impedance:  2V RMS, max at MSB (0dB)/1,25 k Ω max.
Headphone Output level/Impedance: 7V RMS max. At MSB (0dB)/ 250 Ω
Power Supply:  110, 120 220, 240 V AC 50/60 Hz
Power Consumption:  25 Watts
Dimensions (W x H x D):  430 x 90 x 270 mm

Weight:  4,5 kg net

B&W DM 100

 B&W DM-100 Stand-mount/Bookshelf loudspeaker system

Product Summary
 The DM100 is a compact 2-way system created for small rooms.
 Advanced technology was employed to actively reduce the number of components in the crossover.
  
Technical highlights
Refinements in the enclosure give the DM series reduced in lower mid-band coloration and a dramatic improvement in transient response.
Advanced optimisation techniques employing modal analysis of the cabinet structure were a design feature of the enclosure in all four monitors. 
Specifications
Drive Units:
1 x 26 mm dome/coil construction of special polymide material
1 x 150 mm nominal piston dia and 26 mm high temperature voice coil with critically impregnated composite short fibre cone
Frequency Response:   80 Hz to 20 kHz ± 3dB
Sensitivity:  89 dB (2.83V, 1m)
Power Handling:  10W – 75W
Dimensions (H x W x D):  370 x 220 x 210 mm

Finish:  American Walnut or Black Ash vinyl

B&W DM 100i

 B&W DM-100i Stand-mount/Bookshelf loudspeaker system
Product Summary
The DM100i is a compact 2-way system described as a perfect example of what might be called small room sound technology

Computer technology ensures components are kept to a minimum in the crossover.

 Technical highlights
Modal analysis techniques revealed a simple bonding technique of corner joints could improve rigidity and reduce coloration.
New thinking on crossover design has also led to the provision of higher safe power handling and fuse protection overload.
The driver chassis have non-magnetised castings for all the bass midrange units ensuring resonant free high-level sound of the highest amplitude.
Specifications
Drive Units
1 x 26 mm high-frequency driver with dome/coil construction of special polymide material
1 x 150 mm nominal piston dia and 26 mm high temperature voice coil with critically impregnated composite short fibre cone
Frequency Response:   80 Hz to 20 kHz ± 3dB
Sensitivity:  89dB spl (2.83V, 1m)
Power Handling:  10W – 75W
Dimensions (H x W x D):  370 x 220 x 210 mm

Finish:  American Walnut or Black Ash vinyl

C.E.C. ST-540

Direct Drive Quartz-lock Fully Automatic Turntable
Model ST-540's direct drive and fully automatic operation provide perfection and highest quality. Quartz-lock insures  that the turntable rotation will not vary under changing load or voltage. Rotation precision is maintained at ±0,0001% and rumble has been almost eliminated. Wow and flutter have been reduced to negligible levels by improvements in the direct drive.


The Low mass, straight tonearm, is statically balanced for improved tracability, has a removable headshell and antiskating device. The optional moving magnet (MM) cartridge with diamond stylus assures faithful reproduction for the utmost in listening pleasure.
Acoustic feedback reduced.
Improvements made in the subchassis have greatly reduced acoustic feedback. The independent suspension of the floating chassis improves howling performance and pushing the operation buttons does not move the chassis. The hefty, solid base stands firmly in place when the operation buttons are pushed.

All-front operation.
All operations are by feather-touch buttons located on the panel. Even cueing can be performed with the dust cover closed. Operational simplicity is combined into this convenient arrangement.
Fully Automatic operation
Simply place your favorite record on the platter, close the dust cover and push the button. That is all it takes for this fully automatic turntable. Lead-in is automatic and the tonearm will return to rest and turn off power when the record ends.

Oil-damped cueing.
The delicate stylus needle is gently lowered into the record groove with oil-damped cueing. Thus you are now assured of safer and easier record play with no impact shock when the needle contacts the record.
Specifications
Turntable
Motor:  Quartz-phase locked direct drive motor
Sppeds:  33-1/3"  and 45"  r.p.m.
Wow & Flutter:  0,035% (WRMS);  ±0,06% (DIN 45507)
Rumble: 
Unweighted : 40 dB (DIN 45539A)
Weighted : 68 dB (DIN 45539B)
Turntable Platter:  308 mm aluminum alloy die-cast
Tonearm
Type:  Straight-line tubular, static balence type with removable headshell and antiskating device
Effective length:  222 mm
Overhang:  16,8 mm
Adjustable Tracking Force:  0 -2.5 g with direct readout weight
Usable Cartridge Weight:  4 - 6.5 g
Cartridge  model MM3 (Optional)
Type:  Moving Magnet Type,  0,6mil diamond stylus
Frequency Response:  20 - 20,000 Hz
OUTPUT voltage:  3 mV  ±3 dB at 1 kHz  3.54 cm/sec
Channel Balance:  Within 2 dB at 1 kHz
Channel Separation:  more than 18 dB at 1 kHz
Load Resistance:  47 kohm
Weight:  4,6 g w/ spacer
Optimum Stylus Force:  1,8 g
General
Functions:
Automatic start (for 30 and 17 cm records), automatic return, automatic shut off and repeat.
Power Source:  220V 50 Hz for Europe; 120 V 60 Hz for North America
Power Consumption:  6 watts
Dimensions:  416 x 116 x 362 mm
Weight:  5,6 kg