A Smart Turntable from JVC
JVC QL-Y5F turntable automatic single-play turntable with base, dust cover, and servo-controlled tonearm. Dimensions: 19 by 16 3/4 Inches (top), 6.75 inches high with cover closed; additional 11 3/4 Inches vertical clearance and 3 inches at back required with cover open.
Price: $450. Warranty: "limited," one year parts and labor. Manufacturer: Victor Co. of Japan, Ltd., Japan; U.S. distributor: U.S. JVC Corp., 41 Slater Dr., Elmwood Park, N.J. 07407.
TURNTABLES--ALONG WITH just about all other types of components--have been getting smarter over the last few years. Yet the price for all that newfound brainpower has been getting much smaller, pound for pound. No better ex ample comes to mind than JVC's versa tile and utterly automated QL-Y5F. in which even the motion of the tonearm is under computer control. Like Sony's effort in this genre (PS-X75, test reports, November 1980), it incorporates an electronic servo system that constantly maintains correct tracking force while damping out the main low-frequency arm/ cartridge resonance.
Far from being just an exercise in whiz-bang technology, such an electronic damping system serves a vital function, freeing both designer and consumer from the otherwise painful di lemma posed by the mix-and-match philosophy fundamental to componentry.
By smoothing out the low-frequency resonance, a servo system can make a tonearm of almost any mass work well with almost any cartridge, making the arm truly universal and eliminating a major source of audiophile frustration.
Apart from the servo "sidecar" riding next to the pivots, the arm on the QL Y5F is fairly conventional, with its dynamic balance, standard "universal" plug-in headshell, and S-shaped tube. Balance is set via a rotatable counter weight, tracking force and antiskating on a single calibrated dial to the right of the arm rest, damping factor on another dial.
Arm height, cartridge tilt, and overhang also are adjustable. the last facilitated by a calibrated sliding cartridge-mounting plate. Stylus-overhang adjustment re-quires the use of calibration marks on the headshell: but it is not much help be cause of the difficulty of ascertaining the horizontal distance between the stylus tip and the centers of the cartridge mounting holes. which is very awkward to measure to the necessary degree of accuracy. Had JVC included a separate overhang gauge or alignment protractor, it would have made the overhang adjustment easier. especially for the audiophile who has several pickups.
Controls for the quartz-lock direct drive all are accessible in front of the dust cover for ease of operation. Turntable speed (33 or 45 rpm) and record size (12 or 7 inches) are set with separate switches, enabling the QL-Y5F to handle 45-rpm audiophile discs automatically. Punching the START/STOP button causes the platter to begin spinning and the tonearm to lift from its rest and move to the lead-in groove of the record.
(As with most other automatic turn tables. care should he taken not to activate this function without a record on the turntable, lest the stylus catch on the platter mat and be damaged.) At the end of the disc or when you push START/STOP a second time, the tonearm automatically returns to its rest. The entire cycle is very smooth, but record cleaning is a little more inconvenient than it would be if operation of the turntable proper were divorced from operation of the tonearm.
As it stands, a user must hit START/STOP to spin the platter, then the arm-lift but ton to keep the stylus from going into the groove before the cleaning operation is complete. The base of the turntable, which has a beautiful shiny vinyl finish that comes the closest we've ever seen to the look of wood, rests on four adjust able isolator feet.
Lab data are uniformly excellent. Speed accuracy is essentially perfect over a wide range of line voltages, and both rumble and flutter are (as we have come to expect from the best direct-drive turntables) very low. DSL found the calibration of the stylus-force dial acceptably accurate throughout its range (with a maximum error of 1/3 gram at the 3-gram setting) and excellent in the most--used range around 1 gram. Capacitance of the arm wiring and 40-inch connecting cables is a low 105 picofarads.
The action of the servo is evident in the resonance figures (obtained using our standard pickup), which show unusually low resonance amplitudes and an inversion of the usual frequency ordering. with the lateral resonance occurring at a higher frequency than the vertical. DSL also noted that the arm's resonance peaks are uncommonly broad and flat, as one would expect from a heavily damped system.
Use tests confirmed the servo system's effectiveness. Even very compliant cartridges tracked with utter grace and stability, sailing effortlessly over warps that ordinarily would have had them dancing madly in an undamped arm as massive as this one. But the turntable's suspension is not particularly effective in suppressing acoustic feedback, so some users may want more isolation in order to ensure the full measure of performance.
We found the QL-Y5F a consistent joy to use and remain amazed that JVC can offer such fine basic performance plus a sophisticated electronic arm-damping system at so reasonable a price.
Many other audiophile-grade turntables do a great deal less while selling for a good hit more. The QL-Y5F is going to be a tough act for these others to follow.
SPEED ACCURACY (at 33 or 45 rpm) no measurable error, 105 to 127 VAC
WOW & FLUTTER (ANSI/ IEEE weighted peak) 0.04% average. ± 0.05% maximum
TOTAL AUDIBLE RUMBLE (ARLL) -67.5 dB
TONEARM RESONANCE & DAMPING (with Shure V-15 Type III)
vertical 6.5 Hz; 6 dB rise
lateral 9 Hz; 1 dB rise
STYLUS-GAUGE ACCURACY no measurable error to 1 gram; gauge reads 10% high above 1 gram
TOTAL LEAD CAPACITANCE 105 pF
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(High Fidelity, Jul. 1981)
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