MANUFACTURER'S SPECIFICATIONS:
Motor: 20-pole, 30-slot, d.c. brushless.
Speeds: 33 1/3 & 45 rpm.
Drive: Quartz controlled, direct drive.
Wow & Flutter: Less than 0.025 percent W rms.
Rumble: -72 dB (DIN-B).
Fine Speed Adjustment: ±2.5 percent.
Tonearm: S-shaped, tubular with damping, and two-point pivot support.
Dimensions: 19 1/8 in. (48.9 cm) W x 6 5/8 in. (16.8 cm) H x 15 3/8 in. (38.7 cm) D.
Price: $440.00
Sansui makes no fewer than nine turntables which cost from around $100.00 to more than $500.00. The unit selected for this review is number two in the range and uses a 20-pole, 30-slot, d.c. brushless, direct-drive motor in conjunction with a quartz-crystal servo-control system. A frequency generator built ,into the motor provides the error pulses or signals. All the controls are mounted along a narrow front panel, including the easy-to-use cue control. A large On/Off bar switch is first at the far left, followed by two speed-selector buttons, while a third button switches the quartz control out of circuit. A strobe light comes next in line, then the pitch control, and finally the cue control, which is somewhat larger than most, being in the form of a wide lever switch measuring more than an inch square.
The tonearm is a statically balanced S-type, and measures 9-1/16 inches from pivot to stylus. Sansui calls this type of arm "MCF Stabilized" (Mass Concentrated Fulcrum) because it employs a wide brass holder coupled to the support bracket by a horizontal pivot-bearing system. The mass of this sup port system is highest at the fulcrum--the advantage, ac cording to Sansui, being a low moment of inertia with a stable fulcrum point, while extended pivot-to-pivot width prevents dynamic torsion.
The tonearm itself is made of polished aluminum filled with damping material, while the base is constructed from zinc alloy. A rubber damper decouples the rear balance weight, and the anti-skating force is provided by a suspended bias weight that can be set from 0.5 to 2 grams on its calibrated rod. There is an adjusting screw for the arm height, and the aluminum die-cast headshell can be rotated for ac curate alignment. The die-cast platter weighs 3.7 lbs., and strobe markings are cut into the polished edge. The turntable base is constructed of 1 1/2-inch, high-density particle board, heavily lacquered, with a glossy black finish. The unit stands upon four shock-absorber feet, employing a combination of springs, rubber, and felt to give maximum isolation and minimize the possibility of acoustic feedback. The 838 comes with a "free-stop" hinged dustcover which, by the way, covers the front controls when shut.
Measurements
For test purposes a Shure V-15 Mark IV phono cartridge was mounted in the headshell, and both the tracking force and anti-skating adjustments were set for 1.7 grams. The first measurement was for wow & flutter, and the combined figure came out at a low 0.03 percent using the DIN 45-507 standard. Switching the quartz-crystal control off increased the figure to 0.09 percent. Rumble measured a very satisfactory-63 dB (ARLL) which roughly corresponds to Sansui's DIN B specification of -72 dB. The fine speed adjustment gave a variation of ±2.5 percent, as claimed. Tracking error was less than 0.5 degrees per inch and, as expected, both lateral and vertical arm friction were too low to measure accurately. The arm resonance was 8 Hz, showing a rise of 5 dB, but this was lowered to 1.5 dB when the Shure cartridge's stabilizer brush was lowered. Tracking force was found to be accurate within 5 percent, and the anti-skating device matched quite well. However, so much depends upon the cartridge used, it is possible that the optimum anti-skating force will be higher than the tracking figure, especially when this latter is below 1.5 grams.
Listening & Use Tests
The 838 turntable was used for a period of several weeks with great satisfaction. The cue control, in particular, was a real pleasure to use ... not only is it placed in a convenient position, but it is very gentle in operation, with a minimum of backlash.
Another interesting feature of the 838 is the electronic speed changer: If the platter is rotating at 45 rpm and the 33 button is depressed, then that speed is effected almost immediately because a reverse drive current is generated. The strobe light is powered from the quartz-locked system, not from the line voltage. Although, in theory, the frequency of the a.c. power line does not vary in this country, there is another advantage in this arrangement. As the strobe illumination is always synchronized with the servo frequency, only one strobe pattern is needed. A small point perhaps, but refinements like this, plus a better than average tonearm, make this Sansui SR-838 a really excellent value for the money one pays.
-George W. Tillett
(Source: Audio magazine, Feb. 1979)
Also see: Shure V15 Type IV Phono Cartridge (Feb. 1979)
Sansui PC-X1 PCM Digital Processor (Jan. 1984)
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