Ortofon RS-212 tonearm John Wright 1970

John Wright wrote about the Ortofon RS212 in January 1970 (Vol.2 No.10):

Mounting: By boring one hole and inserting three screws, all of whi~ch are positioned by means of a metal template and plastic mounting pillar. These proved to be accurate. No overhang adjustment or alignment protractor is provided, although the exact position of the cartridge in the headshell may be slightly altered via the cartridge-mounting plate.

Cartridge acceptance: An additional screw-in weight is provided in the counter-balance, and with this inserted the arm would balance for cartridge weights between 14 and 22 gm. Without the extra weight, it balanced out between 6 and 13 gm, although these figures will be slightly modified by the use of the cartridge-mounting plates in the headshell. Since the stylus force is applied by a spring arrangement, no additional allowance must be made for it.

Headshell: The headshell by itself weighed 8 gm. To this must be added the weight of the cartridge-mounting plate, of which two are supplied. One, weighing 1 gm, has fixed but reversible mounting holes, to provide a choice of two overhang positions 1/16" apart. An alternative plate, weighing 4.5 gm, allows for greater adjustment via a slotted mount, but since the screw holding this is not countersunk, it was impossible to mount the cartridge flush with the plate as the head of the screw protruded.

Height adjustment: The arm mounts turntables of 1.1875" to 2.175" height, adjustment being made by an Allen screw holding the main pillar.

Lifting device: This was part of the pillar assembly, was damped in action, and functioned most satisfactorily.

Cables: Cables measuring 57" are supplied, to plug in at the base of the arm, and are terminated by standard phono plugs. Capacitance measured 140pF per lead.

Lateral balance: Due to the "S" shape of the arm tube, some degree of torsional balance is achieved by the mass of the cartridge being in line through the pivot with the mass of the counterweight, although the success of this arrangement will depend on the weight of the cartridge used. Lateral balance is maintained through the use of springs rather than weights to provide tracking force and bias compensation.

Damping: Without dismantling the arm, we could find no signs of any kind of damping.

Stylus force: A single spring is used to apply both stylus force and bias compensation. After setting the arm for zero gm, the stylus force is applied by rotating a knurled thumb screw on the counterweight. Because of the spring tension, stylus force will vary slightly with record warps, but the calibrations were in any case found to be rather inaccurate (footnote 1). With bias compensation applied, the stylus force tended to increase as the arm swung toward the inside of the disc, and the extent of this variation depended upon the amount of compensation applied. To accommodate all likely settings of stylus force and bias correction at all points across the record, it would be safest not to assume a calibration accuracy of better than ±20& particularly over the range of 0 to 2 gm.

Bias compensation: Applied by slight lateral displacement at the termination on the pivot of the stylus-force spring. It is basically frictionless, which says much in its favor. It need only be set once at the outset, as its effect is automatically adjusted with the stylus force adjustment. Slight errors above and below the nominal setting were observed across the record, but in view of the changes in stylus force, the device was on the whole quite effective. Because of the lack of precision of the whole arrangement, no appreciable differences were found between the bias requirements for spherical and elliptical styli.

Friction: With the spring disconnected, lateral friction varied across the record between 73mg and 182mg, giving a nominal figure of 90mg. Vertical friction was quite low at only 17mg.

Effective mass: Using the small mounting plate in the headshell, and with the additional rear counterweight removed, the effective mass for balance of a 7 gm cartridge was 17 gm.

Comments: Once the instructions had been fully understood, the arm was relatively easy to set up and adjust and extremely easy to use. Although the mounting arrangement provides for accurate positioning of the main pillar, an alignment protractor would be of value when installing the cartridge. The arm cannot be seriously considered for use at forces of below 1½ gm, but it is likely to give years of robust service in professional applications.—John Wright



Footnote 1: We did not find this to be the case, once the knurled screw had been set to its zero point according to the instructions. We did in fact find the calibrations to be accurate to within 1/8 gram.—Ye Ed.
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David Harper's picture

who would have thought that in 2017 we would be reviewing tonearms and cartridges? This is what I love about audio. It never changes. I love vinyl even though I know that it's primitive tech that cannot possibly(in theory) sound as good as digital. But still, to me, it sometimes sounds better. Maybe because it's actual sound recorded physically in a record groove. Instead of sound converted to some soulless mathematical number stream. Maybe it loses something in that conversion. Something which can never be retrieved. Something having to do with real live music listened to in a real live venue. Maybe digital is like computer generated virtual reality, and analog is actual first hand reality. Is that plausible?

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