REWIRE YOURSELF

REWIRE YOURSELF

Turntable Trauma

Richard Robinson

The most misunderstood and abused component in a stereo system is the turntable that plays the records. The majority of people out to buy a new stereo concentrate on the quality (and cost). of the amplifier and speakers. They sigh with relief when the hi-fi salesman throws in a Garrard 630S turntable with a Pickering V15 cartridge for an extra $55. Unfortunately, bargain,turntables are likely to drastically affect the overall performance of any stereo. Even serious audiophiles in search of the absolute sound with their $500 to $900 turntables have begun to worry that their turntables are wreaking acoustic havoc with their stereo systems.

In the old days, turntables were called record changers and the buyer’s biggest concern was how many records could be stacked on the changer’s spindle. Today changers are called turntables and very, very few of them play more than one record. The extra mechanism required to drop a half dozen albums onto the platter have been abandoned in an all-out effort to play just one record properly. This effort has yet to be 100% successful.

Turntables have two basic functions. First, to spin the record at precisely 33V3 revolutions per minute. And second, to translate the wavering impressions cut in the walls of the record’s grooves through the stylus-cartridge-tonearm into electrical signals that are amplified to drive the speakers.

Manufacturers have taken several approaches to get their turntables to rotate exactly and consistently at 33V3 revolutions per minute. The trick is to turn the metal platter on which the record lays at exactly 33V3 rpm using a motor that runs without fluctuation. Until five or six years ago, turntable platters were'turned by a belt that wraps around the outer diameter of the platter and the shaft of an electric motor located in the turntable base. This rubber band system is still currently used in less expensive turntables like Garrard’s 630S, BIC’s 20Z, and Pioneer’s PL-514, all of which sell for under $100. Belt drive turntables have problems. In time the belt may stretch, hampering the 33V3 accuracy required of any turntable. Belt drives also produce wow, flutter, and rumble that can distort the overall sound coming out of the speakers. On the other hand, there are some belt drive turntables, such as the famous AR Turntable, that are simple, dependable, and inexpensive.

The dependability of platter rotation was advanced by the introduction of direct drive turntables several years ago. In this turntable the motor sits directly underithe platter with the the platter as an extension of the motor shaft so that they turn simultaneously in a 1 to 1 relationship. At first direct drive turntables were very expensive, and there were some problems with the consistent accuracy of the motor revolving at 33t/3. This led to the introduction of the quartz direct drive turntable. In these, the motor is controlled by a quartz crystal whose occilations are used to pin-point the exact motor speed.

Direct drivte turntables now sell for $125 to $175. Direct drive turntables controlled by quartz crystal occilators sell for $175 to $400. Many of the direct drives have built-in stroboscopes that let the user correct turntable speed to exactly 33V3 and 45 rpm. Ultimately, direct drive turntables are mope capable than belt drives of low distortion and minimum turntable rumble. Medium priced direct drives include the Pioneer PL-518, Dual 606, Sony PST-25, and Technics S1-D3. High priced, state of the art quality quartz direct drives include Kenwood’s KD-750; Technics’ SL-1600MKII, and Pioneer’s PL-^3Q.

Turntables are often advertised as manual, semi-automatic, and automatic. When record changers were prevalent, these terms indicated how a multiple stack of records were dealt with by the changer. Being smart guys, the manufacturers kept the terminology, but changed the meaning. Today, automatic turntables are turntables whose tone arm automatically lifts up, find the first groove, plays the record, then lifts up again to travel back to the tone arm rest. Semi-automatics lift the tone arm at the end of the record, but you’ve got to put the stylus in the groove at the start of the record. Manual tone arms don’t do anything; you have to lift them up, put them on the record, and lift them up again when the record is finished to keep them from playing the label. Semi-automatics are best, since they offer the convenience of not having to get up when the record’s over, but don’t put the stylus in the first groove, which is better done by hand using the cueing arm.

Even though manufacturers have successfully applied space technologyto platter rotation, they and their computers are still having a great deal of trouble figuring out how to play the record with the stylus-cartridge-tone arm assembly. Their basic problem is that the record itself is more of a sow’s ear than a silk purse. Most record companies do a slipshod job of pressing their records, and this is a major problems since no hi-fi system, no matter how expensive, can sound good when there’s a poorly pressed record on the turntable. But the biggest problem is that the stylus that cuts the grooves in the original master record bears little resemblance to the stylus on the turntable tone arm that later tries to get the sound back out of those grooves.

This is a technical problem with sophisticated parameters and ramifications that I won’t bore you with. In fact, this whole area is so complicated and subjective, that it is impossible to deal with logically. Some of the very high priced turntables don’t even include a tonearm, the user being expected to buy one separately (for an additional $100 to $200) and mount it on the turntable base himself. This lunatic fringe will also lose sleep over what kind of cartridge to buy for another $100 or so: Shure hyperelliptical, Stanton stereohedron, or Pickering quadrahedral. Or maybe an Audio-Technica nude elliptical. These designations describing the shape of the tip of the stylus that will ride in the groove. The true madmen in the field are also concerned with the capacitance of the stylus-cartridge signal as it is presented to the amplifier for amplification to the speakers. The'end result of all this is that they don’t have much time to play records.

It is important that the stylus-cartridge-tonearm track, read, and translate the cuts in the groove walls as accurately as possible. But right now in this area there's more mythology than technology. There’s not much ybu can doabout the problems involved (even understanding the problems involved is difficult), so it’s best to pretend I never mentioned it.

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If you plan to take care of your turntable, and promise to clean and de-static your records before you play them, then you should get a turntable with a lightweight tonearm and use a moderately expensive cartridge such as the AudioTechnica 15EX, the Staton 681EE, or the Shure Super Pro 1. If you don’t care, a cheaper workhorse cartridge will last longer and be'less fragile. Among, those are the Shure M991ED, the Acutex M307IIE, and the Pickering XV 15/62SE —any of which you can get for around $30.

With a reasonably good turntable (that translates into spending from $130 to $160) and a decent cartridge ($45 or so), you will get the best possible sound out of your records. It won’t be perfect, but until better records are pressed, the quest for perfect will only make it more audibly apparent how badly records are made.

A few tips: proper accessories and maintenance'will help your records sound good. A bubble level and shock pads can make the turntable absolutely horizontal and isolate it from stray vibrations. A disc stabilizer will hold the record more firmly to the platter. A stylus cleaner and brush is better than your finger for wiping dust off the tip of the stylus. A record cleaner, such as Discwasher, and static eliminator, like the one made by Empire, are essential to prepare your records for play. With a little care on your part, even the most humble turntable and stylus will sound better. .