MANUFACTURER'S SPECIFICATIONS
Speeds: 33 1/3 and 45 rpm. Motor: Direct-drive servo type.
Turntable: 12-in. die-cast aluminum alloy. Wow and Flutter: Less than 0.05%. Tracking Error: ± 1.5 degrees. Stylus Pressure: 0 to 4 grams. Dimensions: 19 in. W. x 13 in. D. x 6 in. H. Weight: 19.8 lbs. Price: $319.95.
These days, the most expensive turntables almost invariably use some kind of servo-control system to keep the speed constant and relatively free from wow and flutter. The drive methods vary; one is to use a high-speed motor with a belt reduction drive, and another is to have a slow-speed motor directly connected to the turntable spindle. The Kenwood KP-5022 works on this latter principle, and the motor is a brushless type, servo-controlled by a switched amplifier to give speeds of 33 1/3 and 45 rpm. The unit has several novel features, and its specifications put it among the best half dozen turntables now available.
Fig. 1--Close-up view from above, showing arm and operating controls.
The baseplate is very solid looking, finished in dark brown which makes a nice contrast with the satin-aluminum knobs and other fittings. It is mounted on a low-profile wooden base finished in light walnut. The arm is tubular and is counterbalanced. It is tapered to an elliptical shape near the pivot, and the plug-in head is held by an ingenious clamping device. The cartridge is mounted on a slotted base which permits accurate tracking adjustment. All you have to do is to move the cartridge backwards or forwards until the stylus is immediately above a tiny indicator light on the baseplate, and that's it. Pressure is adjusted by rotating a collar just behind the pivot after the counter-weight is adjusted so the arm balances. The collar is calibrated in grams from 0 to 4, and there is an anti-skating control with similar calibrations.
At the front of the unit on the left is a small raised panel on which is mounted a speed-change lever for 33 1/3 and 45 rpm together with a pair of neat thumb wheels that give a speed variation of plus and minus 3%. On the right hand side is a large push-button marked Play/Cut and a smaller one for Repeat. Behind that is a cue lever and then the anti skating control. At the back is a slide-selector switch marked 30, 25, 17, and Manual. The figures are, of course, in centimeters, and refer to record sizes of 12, 10 and 7 inches, but whether we like it or not, we will soon have to get used to that metric system! The baseplate is spring mounted to the wooden base, which in turn has four spring-loaded feet-what Kenwood calls "insulators." Thus, there are two mechanical compliances in series to prevent acoustic feedback-a method I have long recommended. The time constants must be different for the scheme to be really effective, and I was pleased to note that this is the case with the 5022.
The turntable weighs 3 lbs. 5 oz. and its metal parts are made from non-magnetic material. It has a heavy, ribbed rubber mat, and there are four strobe markings around the perimeter of the platter, two for 50 Hz and two for 60 Hz. A voltage selector is located underneath, and it is a simple matter to change the unit for operation on 200-240 volts.
The dust cover is made of strong plastic about 3 millimeters (all right, 1/8 inch!) thick, and the hinges enable it to "stay put" in any position.
For automatic operation, the selector lever at the rear is set to the appropriate record size and then the Play/Cut button is actuated. At the end of the record, the arm returns to its rest position and the turntable comes to a stop. If you wish to stop playing the record before it is finished, you have to operate the Play/Cut control again; if you wanted to stop the playing for only a short period, you would use the cue or pause lever. The Repeat button needs no further explanation. Finally, if you want manual operation, the select lever must be turned to Manual in which mode the arm has to be moved by hand to the required position before operating the Play/Cut control. The arm will then descend to its playing position and at the end of the record the automatic return functions as before. Thus, manual operation would be used when it is desired to play only a part of a record.
Measurements
The first measurement was for wow and flutter, and the figure was 0.06%using the DIN 45-507 peak rating. The specifications quote a figure "less than 0.05%" which would correspond to a peak rating of about 0.08% W rms, so it would seem that Kenwood is rather conservative in its rating. The rumble figure was also better than the specified -58 dB as the measurement came out at-64 dB using the ARLL standard. Speed variation was approximately -4% to +3% on both ranges, and there was no change in speed when the line voltage was reduced to 90 or increased to 130 volts. Arm resonance, using an Audio-technica AT-20 phono cartridge, was 8 Hz, and both lateral and vertical friction were insignificant. Tracking error is given as 1.5 degrees, and measurements confirm that it was within the 0.5 degrees per inch common to well-designed offset arms. The automatic stop needed significantly less than 0.5 gram to operate, so high-compliance cartridges tracking at one gram or so can be used. The stylus-pressure control was found to be about 10% low above one gram, that is, a scale reading of 3 grams measured 3.3 grams. The connecting cables, which incidentally plug into standard phono plug sockets at the rear, are special low-capacity ones measuring less than 50 pF, so CD-4 cartridges will give optimum results. Ordinary cables have around 200 pF capacity, which would attenuate the CD-4 high frequency carrier, causing some disconcerting effects.
As mentioned earlier, an Audio-technica AT-20 phono cartridge was used for the tests-mostly with CD-4 records which are more critical as to tracking than are stereo discs.
The cartridge was quite easy to line up-although I did remove the arm rest (it's held by a thumb-screw) so the stylus would come nearer the alignment-indicator light. Both the arm rest and the pivot column heights are adjustable, and the directions in the instruction book are easy to follow.
As with all turntables, it is essential that it be perfectly level, and here Kenwood helps you by providing adjustable feet. A turn to the left increases the height and a turn to the right decreases it. I find a small round level invaluable for this adjustment. It should be placed on the platter or mat and not on the baseplate. I found the controls easy to use, although cue lever operation was not so heavily-damped as I would like. The motor is extremely quiet, and the automatic stop operation was completely foolproof during the testing.
Summing up then, the Kenwood KP-5022 is a well-made, attractively-styled unit that should be considered by all who want a really good single-disc automatic turntable.
-George W. Tillett
(Audio magazine, Sept. 1975)
Also see:
Kenwood KD-5070 turntable (ad, Mar. 1979)
Kenwood Model KA-3500 Integrated Stereo Amplifier (Dec. 1976)
ADCOM Crosscoil XC/VAN DEN HUL Moving-Coil Phono Cartridge (Equip. Profile, Jan. 1982)
A Clutch of Cartridge (Adcom, Grado, Talisman and Decca) (Feb. 1986)
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