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





JVC QL-A51 turntable

Quartz-Locked Auto-Return Direct-Drive Turntable

The QL-A51 from JVC differs from the more expensive QL-F61 in only two ways; lack of both a repeat function and full automation. Otherwise it's the spittin image of the QL-F61, including the precision motor , straight tonearm and up-front controls. From the tip of its cabinet base, it's one of our most attractive models - and musical reproduction will be just as attractive resonance and mistracking have become problems of the past.

Our direct-drive Double-Servo Quartz motor has no core.

Double-Servo Quartz control - a JVC exclusive - keeps a constant check on the actual platter speed, speeding up or slowing down the motor instantly if any speed error is detected. Moreover, the servo motor is of our own design, made by us, and coreless to avoid cogging, the annoying rotational fluttering which can spoil music reproduction. Long-term accuracy and reliability are assured throughout this sophisticated direct-drive turntable.

 

Rigid, non-resonant straight-line tonearm.

Our tonearm is of the straight-line design for a reason. The reason is to better handle record warps and for clean low-frequency response which is even more important now that digital and direct0cut records are available. Vy being low mass, our tonearm keeps its resonance frequency above the warp frequency and the resonant peak itself is suppressed so that the lowest musical signals can be reproduced without a trace of muddiness. Mechanical strength is another important feature for surer tracking and better resistance to damage.

 

Up-front controls for all operations, including arm cueing.

Taking a design tip from the more expensive and elaborate turntables in our lineup, we've given the QL-A51 still more appeal with a system of simplified, up-front controls. All can be used with the dust cover closed. And unlike other models in this price range, even the cueing control is up-front. Every care has been taken to prevent unnecessary record handling - from the manual cue control to the automatic arm lift, return and power shutoff at the end of play.

 


Specifications

Turntable

Type:  Quartz locked auto-return system

Drive Motor:  DC Servomotor

Speeds: 33-⅓ and 45 rpm

Wow and Flutter:  less than 0,025% (WRMS), 0,04% (DIN)

Signal-to-Noise Ratio :  more than 75 dB (DIN-B)

Speed Adjustment Range:  ±6%

Platter:  Die-cast aluminum alloy

Diameter:  295 mm (11-3/5")

Cartridge

Model:  Z-1S

Type:  Moving magnet

Stylus Tip:  0,6 mil. Diamond

Optimum Tracking Force:  1,75 x 0,25 grams (DT-Z1S)

Output:  3 mV (1 kHz)

Frequency Response:  10 to 25,000 Hz

Separation:  better than 25 dB (1 kHz)

Load Resistance:  47 k  to 100 k

Compliance:  30 x 10¯⁶ cm/dyne (Static); 10 x 10¯⁶ cm/dyne (Dynamic)

Tonearm

Type:  Statically balanced straight tubular arm with JVC developed Tracking Hold balancing system and tracking force dial in 0,1 gram steps

Effective Arm Length:  220 mm

Overhang:  15 mm

Applicable Cartridge Weight:  8,5 to 12 grams including headshell

Power Requirements:  110, 112, 120, 220, 230, 240 V 50/60 Hz

Power Consumption: 

Dimensions (W x H x D):  420 x 115 x 355 mm (16-1/2" x 4-1/2" x 14-25/32")

Weight Net:  5,3 kg (11,7lbs)


 

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