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





Wadia 7 Transport


If the essence of music is art, then th eessence of music reproduction is technique. And the quintessence of that technique is Wadia.
As we continue to make pioneering advances in digital reproduction, by applying advanced computer technology and patented programming to leading-edge signal decoding, we place increasingly greater demandads on th eelement of digital technology first in the reproduction chain; the transport.
For, while the New Generation of Wadia Decoding Computers has been engineered to achieve faithful reproduction of the very life of recorded music, the broad symphony of instrumental and vocal nuance, the aural ambience of soundspace, the audibly influential presence of the artists themselves, reproduction comes to naught lest the recorded signal is sent, intact, to these brilliant instruments of sonic  reproduction.


Enter the new generation of Wadia transports - designed, foremost, to ensure absolute mastery of signal recovery in the time domain; the genesis of optimum reproduction.
Wadia's proprietary clocking technology initiates digital timing accuracy at the LSI chip, setting the standard for accurate time-base relationships throughout the chain of digital reproduction equipment.
To isolate signal topology from power-supply generated noise, the Wadia 7 Transport has been engineered with a completely redesigned power supply, housed in its own substantial chassis. A state-of-the-art regulator stage ensures constant voltage sophisticated line filtering delivers a pure AC line feed to two toroidal transformers - the very best of current manufacture as is every component in the Wadia 7.
Enclosure design, too, is an essential element of distortion control and, as a result in a loss of information  which cannot be recreated by improvements later in the system.


Wadia's exclusive rounded-corner design detunes the enclosure from resonant frequencies which would have a negative impact of critical clock and program signals.
As the foundation for fautless signal recovery, the chassis of the Wadia 7, constructed of massive body plates, provides a profoundly stable platform for that most critical of all transport components, the spinning mechanism itself.
To expect near- perfect accuracy from heavy-handed servo-feedback corrections would seem folly. Thus, at the heart of the Wadia 7 Transport is the critically acclaimed P-2S spinning mechanism - an acknow ledged industry standard, utilized outside  the manufacturer's realm only within the Wadia 7.
Its full-size die-cast zinc/bronze disc turntable and stabilizer clamp keeps disc and laser pickup in their precise relative positions. With this dimensional stability and interial damping, servo corrections need only deal with tracking the variable disc rotation speed.
Combine full-disc clamping with a floating suspension system, sophisticated resonance damping design and the use of non-resonant metals - not plastic - throughout its understructure, and the result is a mechanical treatment which has risen to worldwide critical acclaim..

Function selection of the Wadia 7 is equally sophisticated. Sculpteed from a solid block of aluminum, the full-functions remote controller promises a lifetime of faultless service, reducing control intrusions into both cosmetics and mechanical integrity.
It is also your fully remote acces to the Wadia 7's matchless companion in unrivaled digital reproduction, the Wadia 9 Decoding Computer.
Truly, the Wadia 7 Transport brings unerring digital transport to reality, presenting, through Wadia's pioneering use of the Glass Fiber Optical Transmission System, the world's most accurate digital output, and offering for  your audition the essence of the art of music, through the twenty-first centry technique that is Wadia.
The Wadia 7 Transport  feature a complete array of output choices. Un mistakably, our prime choice is Glass Fiber Optics. To maintain compatibility between Wadia transports and all possible subsequent system components, we have included a plastic optics output, a Coax output via BNC, and an output in the AES/EBU  connection system.
Additional user-selected options are adjusted from the real panel of the wadia 7 Transport. Separate adjustments can be made for disc drawer insertion speed and ejection speed, and for display intensity.


Wadia 7 Transport Specifications:
CD Stability:  Vibration-Free Rigid Disc Clamping System (VRDS)
CD Pickup Mechanical:  3-beam, objective lens drive, 780 nm wavelength
2-dimensional parallel drive
Machined Cast-alloy turntable
Precision Servo-sled tracking mechanism
Floating suspension system
Pickup Drive Metod:  Linear motor drive
Disc Diameter:  120mm/80mm
Quality Level:  Level 1, High Accuracy ; EIAJ CP-340 Specification
Four Outputs :
Glass Fiber Optic (850 nm) :  -16dBm
EIAJ Standard Plastic Fiber Optic (665 nm):   -15 to -21 dBm
S/PDIF Coaxial via BNC Connector:  0.5V p-p, 75 Ω
AES/EBU Standard via XLR Connector:  3V p-p, 110 Ω
Power Supply;  2 Toroidal Transformers; 100, 120,2 20, 240 V AC
Enclosure:  Airborne computer quality aluminum plate.
Detuned for Lenz's Law and package parasitic resonances.
Side panel skin effect transitions @ < 20 Hz.
Dimensions: 
Main Unit: 9.625" Wide, 17.875 'I Deep, 6.063" High
Power Supply: 7.375" Wide, 17.875" Deep, 6.063" High
Wright: 
Main Unit : 32 Ibs.
Power Supply :  23 Ibs

KEF Cantata SP1056


KEF loudspeakers are designed to reproduce natural sound, free from exaggerated effects of balance and with the lowest possible distortion. Many hundreds of separate items are used to build a loudspeaker system and the electrical and machanicl interaction of the components will significantly affect the reproduction quality

Loudspeaker drive units.
Every KEF diaphragm is manufactured from plastics or, in the case of larger units, from metal and plastics. These special constructions obviate the wide variations in performance associated with ordinary loudspeakers, and considerably reduce colaoration due to the absence of unwanted resonances in the diaphragm itself.
KEF engineers work with radically new techniques to explore the truth about sound coloration, its causes and prevention. Computer based analysis techniques unfold a more precise and detailed insight into speaker behaviour than was previously possible using conventional research techniques.
To make loudspeaker systems which optimise the performance of individual KEF drive units, recent research has concentrated on the interaction of other critical components with the drive units - the dividing network and the enclosure.

Loudspeaker Enclosures
Resonances in a loudspeaker enclosure are known to cause unwanted acoustic radiation which can ruin the clarity of sound from even the finest drive units. The impulse response compares signals from a single drive unit measured in a simple undamped enclosure and from the same unit in a box to which optimum dampinghas been applied using layers of bituminous damping material.
Enclosure analysis is part of loudspeaker engineering. KEF are noe able to assess objectively the audible effect of enclosure resonances and consequently, each KEF system is critically and consistently damped to minimise resonances and reduce audible coloration.

Dividing Networks
Conventional filter designs assume that the load is a simple resistance, whereas in fact, loudspeakers present complicated loads with frequency dependent impedance characteristics. As a result, traditional loudspeaker dividing networks rarely satisfy the conflicting requirements of smooth amplitude frequency response and desirable impedance characteristics.
An entirely new approach to dividing networks has been developed by KEF. The new technique improves transient behaviour giving a smoother, more transparent sound quality, increased depth perspective, and sharper stereo imaging.

System Study
Detailed objective analysis of the comleted loudspeaker system is aided by another sophisticated KEF computer programme. Three-dimensional plots of cumulative spectra - provide "in depth" displays of speaker response in terms of amplitude, frequency and time. At last it is possible to see the effects of speaker design changes and relate them to sound quality.

Quality assurance

The quality of a KEF speaker is under surveillance and control at all stages of production, commencing with the critical inspection of incoming raw materials and components. Frequent inspection of subassemblies at many subsequent stage ensures a very high standard of consistency and reliability. Final testing is carried out using the most sophisticated techniques. Stringent and effective quality controls enable KEF to offer a Five year warranty on all its products.

Specification:  Cantata
System Type:  Three-way, floor standing
Enclosure Type:  Closed box
System:  SP1056
Drive Units: 
Bass Unit :  B139 (SP1044),
Bass  Unit :  B110 (SP1057),
Tweeter :  T52 (SP1049)
Crossover:  SP1058 and SP1064
Input Impedance:  8 Ω
Rated Maximum Power:  150 W programme
Amplifier Requirements:  15 - 150 watts per channel into 8 Ω
System Resonance:  38 Hz, Q=0.7
Frequency Range:  35 - 20,000 Hz, ±3 dB
Sensitivity:  8 watts for 96 dB at 1 m and 400 Hz in anechoic conditions
Crossover Frequencies:  250 and 3000 Hz
Internal Volume:  60 litres
Finishes:   Walnut or Teak
Grille:  Mokka brown cloth
Dimensions (W x H x D):  815 x 340 x 392  mm (32.1" x 13.4" x 15.4")
Weight:  31.7 kg (70 lb)

KEF Calinda SP1053


The Calinda three-way loudspeakers are among the first KEF model to benefit from the technological innovations introduced by the Company during the early and mid 1970s - in particular the application of computer-based test methods in both design and quantity production and the use of the "Target Function Concept" in the synthesis of crossover networks. These advances have made it possible to produce loudspeakers in the domestic size and price range with a standard of performance hithero associated with professional equipment. Like most other loudspeaker, Calinda have been designed to meet aesthetic requirements imposed on them as articles of furniture, and as a result, the outward appearance shows no sign of their special technical features. 

Howev, with the grille covers removed, as shown above, certain differences in the type and positioning of the drive units, and it will also be noticed that in Calinda and largest KEF Cantata, the conventional placing of the mid-range and high-frequency units is reversed.
These features, the reason for which may not be immediately clear, are in fact part of an overall system-engineering approach, in which the various components of each model - drive units, enclosures and filter networks - are developed together and optimised to fulfil a particular need; both designs are based on practical considerations of performance and cost-effectiveness, avoiding the kind of over-specification that may look impressive on paper but is irrelevant to the listeners requirements.
 

Calinda was an 8 inch two-way system with an auxiliary (passive) radiator augmenting the low frequency response. This format was used previously in the Cadenza and Reference 104. In the Calinda system the driver layout was adjusted to allow an elegantly slim floor standing cabinet. 

Specification:  Calinda
System Type:  Two-way, floor standing
Enclosure Type:  Passive radiator
System:  SP1053
Drive Units:
Bass Unit : B200 (SP1054),
Passive Radiator :  BD139 (SP1042),
Tweeter :  T27(SP1032)
Crossover:  SP1055
Input Impedance: 8  Ω
Rated Maximum Power:  100 W programme
Amplifier Requirements:  15 - 100 watts per channel into 8 Ω
System Resonance:  28 Hz, mechanical reflex
Frequency Range:  40 - 30,000 Hz, ±3 dB
Sensitivity:  12.5 watts for 96 dB at 1 m and 400 Hz in anechoic conditions
Crossover Frequency:  3,500 Hz
Internal Volume:  45 litres
Finishes:   Walnut or Teak
Grille:  Mokka brown cloth
Dimensions (W x H x D):  700 x 280 x 350 mm (27.5" x 11" x 13.8")
Weight:  19.1 kg (42 lb)

KEF Corelli SP1051


 Recent developments in loudspeaker engineering and new analysis techniques for evaluating acoustical performance, have resulted in KEF preparing three new loudspeaker products featuring:
Computer design filter sections of advanced specification.
Enclosures heavily damped and braced to minimise colouration
Generous power handling capabilities.
Corelli was an 8 inch two-way closed box system that built on the success of the Chorale. The developments included a new version of the B200 bass unit and an improved cabinet. 
 KEF Corelli features:
Compact shelf mounting 2-way system supplied in mirror image pairs
Generous power handling capabilities
Specification:  Corelli
System Type:  Two-way, bookshelf/stand-mount
Enclosure Type:  Closed box
System:  SP1051
Drive Units: 
Bass Unit :  B200 (SP1063),
Tweeter :  T27 (SP1032)
Crossover:   P1052
Input Impedance:  8 Ω
Rated Maximum Power:  50 W programme
Amplifier Requirements:  25 - 50 Watts into 8 Ω
System Resonance:  58 Hz, Q=1.1
Frequency Response:  50 - 30,000 Hz,  ±3 dB
Sensitivity:  19 watts for 96 dB at 1 m and 400 Hz in anechoic conditions
Crossover Frequency:  3,500 Hz
Internal Volume:  18,5 litres
Finishes:  Walnut or Teak
Grille:  Mokka brown cloth
Dimensions (W x H x D):  470 x 280 x 220 mm (18.5" x 11" x 8.6")
Weight:  9 kg (20 lb)