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





Kenwood KX-1030 cassette deck

Most advanced technology of cassette deck design

The KX-1030 achieves electrical and performance characteristics equal to , or better than those of any cassette deck available today at any price. The extraordinary performance of this cassette deck is a direct result of the many years of research and development of dedicated Kenwood engineers, and their desire to achieve a level of performance that goes far beyond the state-of-the-art..

Consider just one performance feature of the KX-1030. there exist a number of cassette decks which incorporate "three-head" design for the purpose of monitoring recordings directly from the tape as they are being made. The KX-1030 provides for such instant playback of recordings, but Kenwood engineers have incorporated independent record and playback heads for this purpose, thereby achieving a performance level not possible with dual-purpose combination record/playback heads. As a result, the KX-1030 provides extended frequency response, wider dynamic range and higher saturation levels - performance qualities that are indispensable for high quality tape reproduction.

 

Flat Drive Belt - the key to further improvement in woa and flutter

The drive system used to transfer rotational energy from the motor to the flywheel can be used to further reduce undesirable wow-and-flutter. A round cross-sectional type of belt, such as that used in most cassette decks, does not provide sufficient contact surface to be used in a precision cassette deck such as the KX-1030. in order to reduce slippage and vibration caused by the subtle, irregular motion that takes place between the flywheel and the drive belt, Kenwood engineers elected to use a flat belt having a width of 5 millimeters. This belt not only reduces slippage because of its large contact surface, but also absorbs vibration caused by the irregular motion inherent in the remainder of the drive system.

Unlike flywheels with V-grooves gouged into their surfaces, the flat, polished surface of the flywheel used in the KX-1030 provides exact concentricity required for precise rotation. Such accurate roundness is difficult if not impossible to achieve with conventional V-grooved flywheels.

 


Vertical Tape Trasport using Independent Belt Drive System

In most cassette decks employing a single-motor drive, one belt is used to drive the tape as well as the take-up reel. In such systems, so long as there is no tape on the take-up reel side, the capstan drive system operates without interruption. However, as tape accumulates on the take-up side, irregularities or "bumps" in the action of the take-up reel may affect the operation of the capstan drive.

In order to reduce wow created by such vibration, Kenwood engineers decided to incorporate two separate belts; one solely for driving the capstan; the other for driving the take-up reel. As a result of this two-belt system, the KX-1030 provides low wow-and-flutter as well as accurate and stable rotation of the capstan, regardless of tape accumulation on the take-up reel of the cassette.

 

Capstan Roundness Accuracy

The capstan used in Kenwood's KX-1030 is machined to the critical roudness tolerance of 0,1 microns, thus reducing another important cause of wow-and-flutter. The capstan roundness chart , indicates clearly the degree of roundness achieved in Kenwood capstans.

Capstan accuracy must be maintained indefinitely, and not only when the cassette deck leaves the factory. In order to maintain this built-in accuracy, Kenwood engineers have incorporated a triangular capstan support system. This three-point support (as opposed to single or dual-support systems used by other manufacturers) can withstand shock from any direction without affecting the mechanical stability of the capstan system. Thus, long term reliability and low wow-and-flutter performance are assured through many years of continued use.

 

High Power, High Torque DC Servo Motor

While the use of a large flywheel in a cassette deck's transport system contributes significantly to stable and accurate rotation of that drive system, driving such a heavy flywheel requires a motor with high rotational torque. Kenwood engineers have incorporated a motor with a rotational torque of 50 gram centimeters in the KX-1030 - compared with approximately 20 gram centimeters of torque provided by the motors used in many other cassette decks. Another important feature of this well designed DC servo motor is that a sudden increase in load (often encountered in cassette drive systems when less-than-perfect cassette tape housing are used) has a negligible effect upon the stability of the tape drive system.

 


Specifications

Type:  Front Loading Stereo Cassette Deck with Dolny System

Track:  4-track 2-channel Stereo/Mono Recording/Playback

Recording System:  AC Bias System (Bias Frequency: 85 kHz)

Erasing System:  Ac System

Tape Speeds:  4,76 cm/sec (1-7/8 ips)

Heads:  Three Ferrite Heads

Recording and Playback Dual Combination Head x 1

Erasing Head x 1

Motor:  Electronically Controlled DC Motor

Fast Winding Time:  Approx. 80 sec. C-60 tape

Frequency Response

Normal Tape :  25 Hz to 17,000 Hz (35 Hz - 15,000 Hz ±3 dB)

CrO₂ Tape :  25 Hz to 20,000 Hz (35 Hz - 18,000 Hz ±3 dB)

Ferri-CrO₂ Tape :  25 Hz to 19,000 Hz (35 Hz - 17,000 Hz ±3 dB)

Signal-to-Noise Ratio

Dolby On (over 5 kHz):  65 dB (Normal Tape ):  67 dB (CrO₂ tape)

Dolby Off :  55 dB (Normal tape); 57 dB (CrO₂ tape)

Total Harmonic Distortion:  less than 1,3% (at 1 kHz, 0VU with Normal tape)

Wow and Flutter:  0,06% (WRMS)

Input Sensitivity/Impedance

Line x 2 :  77,5 mV/56 k  ( or 0,1 mV/1,0 k  )

DIN x 1 :  10,9 mV/1,5 k

Microphones x 2 :  0,19 mV/10 k

Output Level/Load Impedance

Line x 2 :  775 mV (0VU) / 2,0 k

DIN x 1 :  775 mV (0VU) / 2,0 k

Headphones x 1 :  48,9 mV / 8  - 16

Power Requirements:  AC 120 V 60 Hz (USA, Canada); AC 220 V , 50 Hz (Australia); AC 240 V, 50 Hz (UK )

Power Consumption:  13,0 watts

Dimensions (W x H x D):  430 x 167 x 332 mm (16-15/16"x 6-9/16"x13-1/16")

Weight:  7,5 kg (16,5 lbs)


 

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