Like the QL-10 the QL-8 from JVC is also a complete system combining a Quartz-Locked Turntable, model TT-81 in this case, with the CL-P1 Turntable Base and UA-7045 New Gimbal Support Tonearm, the latter two being custom-designed components available separately.
The QL-8 with its TT-81 Quartz-Locked Turntable section delivers the same functional features and advanced control accuracy as the more expensive model; it lacks only the digital speed indicator. Features include the JVC Quartz-Locked Servosystem, the Positive and Negative Servo-control, 1 Hz/440 Hz Pitch Control, Quick Stop facility and more. Outstanding performance features such as highly accurate speed constancy, low wow and flutter, exceptionally high signal-to-noise ratio are all retained.
Quartz-Locked Turntable
Use of the Quartz-Locked Servosystem containing a precision quartz crystal oscillator lets JVC guarantee absolute pitch accuracy, with speed deviation of less than 0,025%. This is a major factor in your assurance of the Musical Truth from JVC
1 Hz Step Pitch Control
With the 440 Hz as the reference pitch, the TT-81 in the QL-8 can be adjusted higher or lower up to 6 Hz in 1 Hz steps. A button control is provided for this purpose. Unlike other Quartz-Locked servos, this one works even while the speed is being fine-adjusted, thus speed accuracy is always maintained.
Positive and negative Servo-control
The JVC servosystem works in both positive and negative directions, again unlike conventional systems. Any speed deviation is instantly rectified to the absolutely correct speed.
Quick Stop
When the Stop Button is pushed, an electronic brake produces a reverse current in the drive circuit that generates reverse motor torque to counteract the motor torque. The platter comes to a full stop within one second.
Integrated Frequency Generator
A second servo, consisting of a frequency generator for speed detection, is an integral part of the direct-drive motor in the QL-8. a disc rotor with 180 slits is coupled with a doughnut shaped magnet. Beneath this is mounted a stator coil for detection, printed on a round-shaped circuit board. Thus, when the motor is rotating, 180 pulses are generated with each revolution as signals to be compared instantly with the quartz-generated reference signal. The integrated frequency generator, by the way, is completely free from error regardless of loads on the platter.
Oscillator-Assisted Stroboscope
In place of the digital indicator in the QL-10, the QL-8 has a highly accurate strobe, illuminated by a neon lamp which flashes at a rate that is synchronized not with power-line frequency as in conventional strobes but instead with the accurate and always-stable quartz-derived reference frequency. Only one row of stroboscopic stripes is needed, and each stripe appears sharp and clean. There is never a doubt that the platter is turning at its correct speed.
Specifications
Type: DC servomotor
Drive System: Direct-drive
Speeds: 33-⅓ and 45 rpm
Speed Detection System: Integrated Frequency Generator
Servosystem: Quartz Servosystem
Pitch Control Range: ±6 Hz (Standard:440 Hz)
Speed Change: Electric switching
Start-up Time: less than 1,0 sec
Wow and Flutter: less than 0,025% (WRMS); 0,045% (DIN)
Signal-to-Noise Ratio better than 73 dB (DIN-B); 63 dB (IEC-B)
Start-up Torque: better than 1,3 kg-cm
Speed Deviation: less than 0,002%
Load Characteristics: 0% (under 100 gram loads)
Drift (hour): 0,0004%/H
Voltage Drift (±10V): 0%
Thermal Drift: 0,00003%/°C
Quick-Stop Time: less than 1,0 sec
Platter
Type: 316 mm aluminum die-cast
Tonearm
Type: Statically-balanced arm with New Gimbal Support on TH (Tracing Hold) System
Effective Length: 245 mm
Tracking Error: +1°48' -1°31'
Overhang: 15 mm
Applicable Tracking Force: 0 - 3 grams (0,25 gram steps)
Applicable cartridge Weight: 12,0 - 32,0 grams
Arm Elevation Range: 40,0 - 60,0 mm
Operation Mode: manual
Dimensions (W x H x D): 510 x 191 x 410 mm ( 20-5/64" x 7-3/4" x 16-9/64")
Weight: 18,5 kg (40,7 lbs)
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