Turntables, Tonearms, and Cartridges

It may come as a surprise to learn that sales of turntables, phono cartridges, and LP records have been steadily increasing since the turn of the millennium. But why would a primitive, early twentieth-century analog technology find growing support in the age of internet downloads and portable digital music players that can store thou sands of hours of instantly accessible music?

The answer has several parts. First, the LP record, when played correctly, has a warmth and musicality unmatched by the CD. Some would even argue that the LP is sonically superior to high-resolution digital formats such as DVD-Audio and SACD. Second, the act of setting up and tweaking a turntable, along with the ritual of put ting a large black disc on a slowly rotating platter, holds enormous appeal for some music lovers. As one turntable distributor remarked to me “Playing LPs is the barbeque of hi-fi; it’s as much about the process as the result.” Third, many young people who never knew the turntable and vinyl records as children are now embracing vinyl for its retro-cool factor In the process, they’ve discovered the musical pleasure the LP can deliver. Finally, putting an LP on a turntable is an act that signifies a single-minded dedication to focusing on the music. When playing a record you sit down in the listening chair, often with full-sized liner notes and cover art, and with no remote control to skip tracks. The process makes a statement that you are about to give the music your full attention for an entire LP side (at a minimum). Compare that experience with listening to music from a portable music player while engaging in some other activity—one’s attention span need be no longer than the time it takes to hit the track-skip button—not to mention the lack of album art and liner notes that are often an important extension of the artist’s expression. Spinning an LP represents a return of listening to a central activity, and a rejection of modern society’s relegation of music to aural wallpaper.

Returning for a moment to the sound of LP vs. CD, it’s worth noting that at the highest levels of music playback, there’s not much of a debate; LP is the clear winner. It’s interesting to see the number of amplifier and loudspeaker manufacturers at hi-fi shows using a turntable and vinyl records to demonstrate their exotic new products. They want to show their new products in the best light and turn to the LP to deliver the highest quality of sound. When done right, LP playback has an openness, transparency, dynamic expression, and musicality not matched by CD. There’s just a fundamental musical rightness to a pure analog source (one that has never been digitized) that seems to better convey the music’s expression.

This isn’t to say that LPs are perfect. They suffer from a variety of distortions such as mistracking, ticks and pops, speed instability, surface noise, cartridge frequency response variations, inner-groove distortion, wear, and susceptibility to damage. But for many listeners, these problems are less musically objectionable than the distortion imposed by digitally encoding and decoding an audio signal. (It’s been said that turning digits back into music is akin to trying to turn hamburger back into steak.) Some listeners can hear past the LP’s flaws and enjoy the medium’s overall musicality. Other listeners can’t stand the ritual of handling and cleaning records—not to mention keeping the turntable properly adjusted—and think CD is just fine. I think of it this way: LP’s distortions are apparent, but separate from the music; digital’s distortions are woven into the music’s fabric. Consequently, analog’s distortions are easier to ignore. If you’re inclined to think CD is without fault, and you’ve never heard a properly played LP give yourself a treat and visit a specialty audio dealer with a high-end turntable. Listen to what vinyl can do before you write off the possibility of owning a high-quality turntable.

With that background, let’s look at the components that make up an LP play back system.

The long-playing (LP) record-playback system is a combination of a turntable, tonearm, and phono cartridge that converts the mechanical information encoded on vinyl records into an electrical signal that can be amplified by the rest of your playback system. The turntable spins the record, the tonearm holds the cartridge in place, and the cartridge converts the wiggles in the record’s groove into an electrical signal. Each of these elements, and how they interact with each other, plays a pivotal role in getting good sound from your system. An LP front-end can be as simple as a $350 turntable/ arm/cartridge combination (Fig. 1) that you take out of the box and plug into your system, or an elaborate rig that literally takes several days to set up and tune (Fig. 2).

Fig. 1 Turntables can be inexpensive and simple to set up and use. (shown: Pro-Ject by Sumiko)

Fig. 2 Some turntables are elaborate, with a sophisticated suspension system. (shown: Basis Audio)

The Turntable

It’s easy to think of the turntable as having a minor role in a playback system’s sound quality After all, the turntable only spins the record and holds the tonearm; how much sonic influence could it have?

The answer is surprising: a high-quality turntable is absolutely essential to get ting the best performance from the rest of your system. A good turntable presents a solid, vibration-free platform for the record and tonearm, allowing the cartridge to recover the maximum amount of information in the grooves while minimizing interference with the audio signal.

The turntable is composed of a base, platter, platter bearing, plinth, drive system, and often a sub-chassis. The base is the turntable’s main structure; it holds all the components, and is usually finished in black or natural wood. The platter is the heavy disc that supports the record; it rests on the bearing assembly. The plinth is the top of the turntable beneath the platter. The drive conveys the motor’s rotation to the plat ter. Some turntables have a sub-chassis suspended within the base on which the platter and tonearm are mounted. Every turntable will also have an armboard for mounting a tonearm. Many turntables have no base or plinth, instead suspending the sub-chassis in open air.

Let’s look at how each of these components is assembled into the modern turntable.

Base and Plinth

A turntable’s base and plinth play important roles in sound quality. The base must be a rigid, vibration-resistant structure on which the other turntable components can be mounted. If the base is flimsy, it will vibrate and transmit that vibration to the platter and tonearm, degrading the sound.

A turntable system can be set vibrating by four forces:

1) acoustic energy impinging on the turntable (called feedback) ;

2) structure-borne vibration traveling through the turntable stand (primarily when the stand is located on a suspended floor);

3) the turntable’s mechanical systems, such as the platter bearing and motor vibration; and

4) the motion imparted to the tonearm by groove modulations.

These sources of vibration create relative motion between the stylus and the cartridge. Because the cartridge can’t distinguish between groove modulation and turntable resonance, this vibration is converted to an electrical signal and amplified by your system. This is why turntable designers go to elaborate measures to reduce vibration.

Let’s first take the case of acoustic energy impinging on the turntable. If the base and plinth aren’t rigid, they’re more likely to be set in motion by sound striking the turntable. In extreme cases, the loudspeakers and turntable create an acoustic feedback loop in which sound from the loudspeakers is converted into an electrical signal in the cartridge through vibration, which is amplified by the loudspeakers, which causes even more feedback to be produced by the cartridge, and so forth. This acoustic feedback can muddy the music, or even make it impossible to play records at a moderately high playback level. You can hear this phenomenon by putting the stylus on the lead-in groove without the record spinning, then gradually turning up the volume. You’ll start to hear a howling sound as the acoustic feedback loop grows strong enough to feed on itself and a “runaway” condition develops in which the sound keeps getting louder. If you try this, keep your hand on the volume control and be ready to turn down the volume as soon as you hear the howl—if you don’t turn down the volume immediately, the system could be damaged. The more vibration-resistant the turntable, the less severe this phenomenon.

So much for the problem of acoustic energy putting the turntable in motion. Now let’s look at how turntable design addresses the problems of structure-borne vibration. Vibration entering the turntable through the stand or rack can be greatly reduced by mechanically isolating the turntable’s key components (platter, armboard, and tonearm/cartridge) with a suspension system—the sprung turntable.

Sprung and Up-sprung Turntables

Most turntables are sprung, meaning that the platter and arm board are mounted on a sub-chassis that floats within the base on springs. The terms suspended and floating describe the same construction.

Sprung turntables can be one of three designs. In one method, the sub-chassis sits on springs attached to the base bottom. In the second method, the sub-chassis hangs clown from the plinth on springs. (diagram below shows the latter of these two techniques.) The third technique dispenses with the base entirely and hangs the sub-chassis in open air on pillars (see image above). The turntable is suspended on the four pillars at each corner of the turntable.

Whichever technique is used, the goal of all sprung designs is to isolate the platter and tonearm from external vibration. Any vibration picked up by the supports on which the turntable rests won’t be transferred as effectively to the platter and tone- arm. The primary sources of structure-borne vibration are passing trucks, footfalls, air conditioners, and motors attached to the building. Structure-borne vibration is much less of a problem in a single-family home with a concrete floor than in an apartment building or frame house with suspended floors.

Fig. 3 The subchassis can be hung from the plinth. (pictured: SOTA Industries.)

Platter and Bearing Assembly

The platter not only provides a support for the record, it also plays two other important roles: as a flywheel, to smooth the rotation; and as a “sink,” to draw vibration from the record. Many platters are very heavy (up to 30 pounds), with most of their mass concentrated toward the outside edge to increase their moment of inertia. This high mass also counters bearing friction and stylus drag. Irregular (non-linear) bearing friction can create rapid irregularities in the platter’s speed, which frequency-modulates the recovered audio signal. Massive platters greatly reduce the audible effects of bearing friction.

Most platters are made of a single substance such as acrylic, stamped metal (in cheaper turntables), cast and machined aluminum (in better turntables), or exotic materials such as ceramic compounds. The platter sometimes has a hollowed-out ring around the outer edge that is filled with a heavy material to increase the platter’s mass, or is loaded with a damping substance to make the platter more inert and resistant to vibration.

These techniques also attempt to make the platter act as a “sink” for record vibration. When the record is clamped to the platter, any record vibration will be transferred to the platter. The platter’s material and geometry are thus important design considerations: The platter should have no resonant peaks within the audioband. Some platters use constrained-layer damping and combinations of different materials to pro vide the ideal sink for record vibration.

Because the platter spins on a stationary object (the rest of the turntable), there must be a bearing surface between the two. With one technique, the bearing is mounted at the end of a shaft to which the platter is attached. This shaft—often made of stainless steel—extends down a hollow column in the base. The shaft has some form of bearing on the end, either a chrome-hardened steel ball, tungsten-carbide, Zirconium, ceramic, or even a very hard jewel such as sapphire. The bearing often sits in a well of lubricant.

A second technique puts the bearing surface on top of a stationary shaft, with the bearing surface between the platter and shaft.

Whichever technique is used, the bearing must provide smooth and quiet rotation of the platter. Any noise or vibration created by the bearing will be transmitted directly to the platter. Turntable bearings are machined to very close tolerances, and are often highly polished to achieve a smooth surface.

A bearing that suffers none of the traditional mechanical problems is the air bearing. The platter rides on a cushion of air rather than on a mechanical bear ing. A pump forces compressed air into a very tiny gap between the platter and an adjacent surface. This air pressure pushes the platter up slightly so that the platter liter ally floats on air. Air-bearing turntables are, however, very expensive and can be difficult to set up. A recent development in turntables is the magnetic bearing, in which the platter floats on a magnetic field. This technique has the advantage of completely isolating the platter, but is enormously expensive to implement.

Platter Mats and Record Clamps

Platter mats are designed to minimize record vibration, and then to absorb what vibra tion remains. Designers of soft mats suggest that an absorbent felt mat works better in drawing vibration away from the record. Designers of hard mats contend that a stiffer mat material better couples the record to the platter. Finally, some turntable manufacturers discourage using any mat at all, believing that their platter design provides the best sink for record vibration.

Record clamps couple the record to the platter so that the record isn’t allowed to vibrate freely (image below). The platter acts as a vibration sink, draining vibration from the record. By more intimately coupling the record to the platter, the record clamp improves the sound.

Record clamps come in three varieties. First, the clamp can simply be a heavy weight put over the spindle. The clamp’s weight squeezes the record between clamp and platter. Other clamps have a screw mechanism that threads down onto the spindle. The third type is the “reflex” clamp, in which a locking mechanism pushes the clamp down onto the record. Which type works best should be decided by your listening, the turntable manufacturer’s recommendations, or your local dealer’s suggestion. Note that very heavy clamps can put a strain on some sprung turntables, compressing the springs (or expanding them if the sub-chassis is hung from the plinth). Some form of record clamping is, however, a must for any high-end turntable.

Fig. 4 A record clamp creates a tight coupling between the record and platter and is essential to good sound.

An extra measure of clamping takes the form of a heavy metal ring whose inner diameter is very slightly larger than an LR When placed over the LP on the platter, this ring couples the LP’s outer edges to the platter. These rings are used in con junction with, rather than in lieu of a spindle clamp.

Drive System

A turntable’s drive system transfers the motor’s rotation to the platter. Virtually all high-end turntables currently made are belt-driven; the platter is spun by a rubber belt or silk thread stretched around the motor pulley and outer rim of the platter.

Fig. 5 Virtually all high-end turntables are belt-driven.

Mass-market mid-fl turntables, when they were still made, were usually direct- drive; i.e., the motor is connected directly to the platter. The motor’s spindle is often the spindle over which you place the record. Direct drive was sold to the public as superior to belt drive—there are no belts to stretch and wear, and a direct-drive motor can be electronically controlled to maintain precise speed and have low wow and flutter. Indeed, the wow and flutter specifications of a direct-drive turntable are generally better than those of a belt-drive turntable.

But, without question, belt-drive turntables sound better than direct-drive models. Rather than directly coupling the motor’s vibration to the platter as in direct-drive, the drive belt acts as a buffer to decouple the platter from the motor. Motor noise is isolated from the platter, resulting in quieter operation than is possible from a direct-drive turntable. Belt drive also makes it easier to suspend the platter and drive system on a sub-chassis.

No elaborate speed controls are used on belt-drive turntables; the motor just sits there spinning at a fairly high speed (as fast as 1000rpm). This high-speed rotation is coupled to the large platter with a small pulley, resulting in 33-1/3 rpm rotation of the platter.

The drive motor can be a source of turntable vibration. As the motor spins, it produces vibration that can be transferred to the other components in the turntable, producing a low-frequency rumble. Even if you don’t hear rumble directly, motor vibration can still degrade the sound. The motor assemblies of some turntables are completely separate from the base and encased in damping material. Other designs mount the motor to the sub-chassis, and isolate its vibration from the other turntable components.

The Tonearm

The tonearm’s job is to hold the cartridge over the record and keep the stylus in the groove. We want the tonearm to be an immovable support for the cartridge, yet also be light enough to follow the inward path of the groove, track the up-and-down motions of record warps, and follow any record eccentricity caused by an offset center hole—all without causing undue wear on the delicate grooves themselves. As we’ll see, this is a challenging job.

Tonearms come in two varieties: pivoted and tangential-tracking. A pivoted tone-arm allows the cartridge end of the arm to traverse the record in an arc while maintaining a fixed pivot point. A tangential tonearm (also called a linear tracking tone- arm, shown in Fig. 2 earlier) moves the entire tonearm and bearing in relation to the record.

Fig. 6 Elements of a pivoted tonearm. (this tonearm was made by Linn)

Let’s take a closer look at the pivoted tonearm, by far the most popular type of tonearm. Its major components are, from back to front, the counterweight, bearing, arm-tube, and head-shell (these elements are shown from left to right in the above image). The counterweight counteracts the weight of the armtube and cartridge; its weight and position determine the downward force of the stylus in the

The bearing provides a pivot point for the arm, in both the vertical and horizontal planes. The armtube extends the cartridge position away from the pivot point to 911 optimum position over the record. The headshell is attached to the end of the armtube and provides a platform for mounting the cartridge to the armtube. The small, flat disc near the bearing sets the anti-skating compensation.

A tonearm’s bearing is an important aspect of its design. The bearing should provide very low friction and not impede the arm’s movement. If the bearing is sticky, the stylus will be forced against the groove wall, causing distortion and record wear. Loosening the bearings reduces friction, but can cause the bearings to “chatter” as the tonearm is rattled by the motion of the stylus in the groove, or by other sources of tonearm vibration. Remember, any movement of the tonearm in relation to the stylus in the groove is interpreted by the cartridge as groove modulation, and is converted into an electrical signal that appears at the cartridge output along with the musical signal. Tightening the bearings decreases chatter but also increases friction. Tonearm designers must balance these tradeoffs.

When playing a record, the tonearm is pulled toward the center of the record, a phenomenon called skating. Skating is a force acting on the stylus that must be compensated for by applying an equal but opposite force on the cartridge. This compensation, called anti-skating, counteracts the skating force caused by tonearm offset. Anti- skating allows the stylus to maintain equal contact pressure with both sides of the groove, and prevents the cartridge’s cantilever from being displaced from its center position in the cartridge. Anti-skating can be generated by springs, weights with pulleys, or mechanical linkages.

The Phono Cartridge

The phono cartridge has the job of converting the modulations of the record groove into an electrical signal. Because the cartridge changes one form of energy into another (mechanical into electrical), the cartridge is called a transducer. There’s one other transducer in your system—the loudspeakers at the other end of the playback chain.

A phono cartridge consists of the cartridge body, stylus, cantilever, and generator system. The body is the housing that surrounds the cartridge, and comprises the entire surface area. The stylus is a diamond point attached to the cantilever (the tiny shaft that extends from the bottom of the cartridge body). The stylus is moved back and forth and up and down by modulations in the record groove. This modulation is transferred by the cantilever to the generator system, the part of the cartridge where motion is converted into an electrical signal.

Moving-Magnet and Moving-Coil Cartridges

Cartridges are classified by their principle of operation: moving-magnet or moving- coil. In a moving-magnet cartridge, tiny magnets attached to the cantilever move in relation to stationary coils in the cartridge body. The movement of the magnetic field through the coils induces a voltage (the audio signal) across the coils. (Diagram shows the essential elements of a moving-magnet cartridge.)

Fig. 7 Moving-magnet cartridge construction.

A moving-coil cartridge works on exactly the same physical principles, but the magnets are stationary and the coils move. A moving-coil cartridge generally has much less moving mass than a moving-magnet cartridge. Consequently, a moving-coil cartridge can generally track better than a moving-magnet type, and also have better transient response. With less mass to put into motion (and less mass to continue moving after the motivating force has stopped), moving-coil cartridges can better follow transient signals in the record. Because of their construction, moving-coil cartridges generally don’t have user-replaceable styli; you must return the cartridge to the manufacturer.

Cartridge output voltage varies greatly between moving-magnet and moving- coil operation. A moving-magnet’s output ranges from 2mV (two thousandths of a volt) to about 8mV; a moving-coil cartridge’s output is typically between 0.l5mV and 2.5mV Although moving-coil cartridges generally have lower output voltage than moving-magnet types, some so-called “high-output” moving-coils have higher output volt age than some moving-magnet cartridges.

This wide range of cartridge output voltage requires that the phono preamplifier’s gain be matched to the cartridge’s output voltage. The lower the cartridge output voltage, the higher the gain needed to bring the phono signal to tine level. (A full discussion of matching cartridge output voltage to phono-stage gain is included in Section 7.)

Stylus and Cantilever

Styli (the plural of stylus) come in a variety of shapes, the simplest and least expensive of which is the conical or spherical tip. The conical stylus is a tiny piece of diamond polished into a cone shape. An elliptical stylus has an oval cross section, with two flattish faces. Because this shape more closely approximates the shape of the cutting stylus, it results in lower tracking distortion.

Keeping your stylus clean is of paramount importance: The stylus should be cleaned before every record side. A speck of dust or dirt is like a boulder attached to the stylus, grinding away at the groove walls. An appreciation of the enormous pres sure a stylus imposes on the groove further highlights the need for a clean stylus. For example, a tracking force of 1.4 grams applied to a typical stylus contact area results in a pressure of nearly four tons per square inch. This pressure is enough to momentarily melt the outer layer of the groove wall. It’s easy to see how stylus motion through the groove is much smoother with a clean stylus, and produces much less record wear. A clean stylus sounds better, too.

A stylus should be cleaned with a back-to-front motion so that the brush follows the record’s motion. Some manufacturers recommend that no cleaning fluid be used; others suggest that a fluid is essential to removing accumulated dirt. There is also debate over the best type of brush. Some have short, stiff bristles, while other cleaners resemble nail-polish brushes. Your best bet is to follow the cartridge manufacturer’s cleaning instructions. And don’t clean the stylus with the tonearm locked in place; you could apply too much force and damage the stylus.

With good maintenance, a stylus should last for about 1000 hours of use. It’s a good idea to have the stylus examined microscopically after about 500 hours, then again at 800 hours to check for irregular wear that could damage records.

Because the cantilever transfers stylus motion to the generator, its construction is extremely important. Cantilevers are designed to be very light, rigid, and non- resonant. The lower the cantilever mass, the better the cartridge’s trackability, all other factors being equal. To obtain stiffness with low mass, exotic materials are often used in cantilever design, including boron, diamond, beryllium, titanium, ceramic, ruby, and sapphire. Cantilevers are often hollow to reduce their mass, and are sometimes filled with a resonance-damping material.

The cantilever is mounted in a compliance inside the cartridge body at the end opposite to that which bears the stylus. The compliance allows the cantilever to move, yet keeps it in position. Because this compliance is stiff when the cartridge is ne it takes many hours of use for the cartridge to break-in and sound its best. It isn’t unusual for a cartridge to continue to sound better after 100 hours of use.

How to Choose an LP Playback System

Because there are many more variables to account for in LP playback, how much of your audio budget you should spend on this part of your system is a more complicated decision than setting a budget for, say, a power amplifier.

Let’s look at two hypothetical audiophiles, one of whom should spend much more on a turntable, tonearm, and cartridge than the other audiophile.

Our first audiophile has a huge record collection that represents a lifetime of collecting music. Her record collection is a treasure trove of intimately known music that she plays daily. Conversely, she has very few CDs, buying them only when her favorite music isn’t available on vinyl. She much prefers the sound of LPs, and doesn’t mind the greater effort required by LPs: record and stylus cleaning, turning over the record, lack of random access.

The second audiophile’s record assortment represents a small percentage of his music collection—most of his favorite music is on CD. His LP listening time is a fraction of the time spent listening to CD. He likes the convenience of CD, and can happily live with the sound of his excellent CD player or universal-disc machine.

The first audiophile should commit a significant portion of her overall system budget to a top-notch LP front end—perhaps 40%. The second will want to spend much less—say, 10 to 15%—and put the savings into the components he spends more time listening to.

A decent entry-level turntable with integral tonearm runs about $300, with an appropriate cartridge adding from $30 to $150 to the price. A mid-level turntable and arm costs $800 to $1500; the cartridge price range for this level of turntable is from $200 to $700.

There are roughly two quality and price levels above the $2000 mark. The first is occupied by a wide selection of turntables and arms costing between $3000 and $6000. At this price, you can achieve very nearly state-of-the-art performance. Plan to spend at least $1000 for a phono cartridge appropriate for these turntables.

The next price level is established by turntables costing between $10,000 and $30,000. A topflight phono cartridge can add as much as $5000 to the price. You should know that a super-stratified class of turntables exists, with some models carrying six-figure price tags. These systems are characterized by extraordinary and elaborate construction techniques.

Once you’ve decided on an LP front-end budget, allocate a percentage of that budget to the turntable, tonearm, and cartridge. Many lower-priced turntables come with an arm—or an arm and cartridge—already fitted and included in the price. At the other end of the scale, the mega-dollar turntables also include a tonearm. In the middle range, you should expect to spend about 50% of your budget on the turntable, 25% on a tonearm, and 25% on a cartridge. These aren’t hard figures, but an approximation of how your LP front-end budget should be allocated, As usual, a local audio retailer with whom you’ve established a relationship is your best source of advice on assembling the best LP playback system for your budget.

An item of utmost importance in achieving good sound from your records is a good turntable stand or equipment rack, particularly if the turntable has a less than adequate suspension. I cannot overstate how vital a solid, vibration-resistant stand is in getting the most from your analog front end. Save some of your budget for a solid equipment rack or you’re wasting your money on a good turntable, arm, and cartridge. (The very best turntables have extraordinary mechanical systems to isolate the turntable from vibration, and thus don’t benefit as much from a solid stand. These turntables are rare, and occupy the upper end of the price range.)

What to Listen For

Judging the sonic and musical performance of an LP playback system is more difficult than evaluating any other component. If you want to audition a phono cartridge, for example, you cannot do so without also hearing the turntable, tonearm, and how the cartridge interacts with the rest of the LP playback system. The same situation applies to each of the elements that make up an analog front end; you can never hear them in isolation. Further, how those three components are set up greatly affects the overall performance. Other variables include the turntable stand, where it’s located in the room, the phono preamp, and the load the preamp presents to the cartridge. Nonetheless, each turntable, tonearm, and cartridge has its own sonic signature. The better products have less of a sonic signature than lower-quality ones; i.e., they more closely approach sonic neutrality.

A high-quality LP front end is characterized by a lack of rumble (or low-frequency noise), greatly reduced record-surface noise, and the impression that the music emerges from a black background. Low-quality LP front ends tend to add a layer of sonic grunge below the music that imposes a grayish opacity on the sound. When you switch to a high-quality front end, it’s like washing a grimy film off of a picture window—the view suddenly becomes more transparent, vivid, and alive.

Even if the LP front end doesn’t have any obvious rumble, it can still add this layer of low-level noise to the music. The noise not only adds a murkiness to the sound, it also obscures low-level musical detail. A better turntable and tonearm strip away this film and let you hear much deeper into the music. It can be difficult to identify this layer of noise unless you’ve heard the same music reproduced on a top-notch front end. Once you’ve heard a good LP playback system, however, the difference is startling. To use a visual analogy, hearing your records on a good analog front end for the first time is like looking at the stars on a cloudless, moonless night in the country after living in the city all your life. A wealth of subtle musical detail is revealed, and with it, a much greater involvement in the music.

Another important characteristic you’ll hear on a superlative system is the impression that the music is made up of individual instruments existing in space. Each instrument will occupy a specific point in space, and be surrounded by a halo of air that keeps it separate from the other instruments. The music sounds as if it is made up of individual elements rather than sounding homogenized, blurred, congested, and confused. There’s a special realness, life, and immediacy to records played on a high- quality turntable system.

A related aspect is soundstage transparency—the impression that the musical presentation is crystal-clear rather than slightly opaque. A transparent soundstage lets you hear deep into the concert hail, with instruments toward the rear maintaining their clarity and immediacy, yet still sounding far back in the stage. The ability to “see” deep into the soundstage provides a feeling of a vast expanse of space before you in which the instruments can exist (if of course, the recording engineers have captured these qualities in the first place). Reverberation decay hangs in space longer, further conveying the impression of space and depth.

Conversely, a lower-quality LP front end will tend to obscure sounds emanating from the stage rear, making them sound undifferentiated and lacking life. The presentation is clouded by an opaque haze that dulls the music’s sense of immediacy, prevents you from hearing low-level detail, and tends to shrink your sense of the hall’s size.

Other important musical qualities greatly affected by the LP front end are dynamic contrast and transient speed. A top-notch LP replay system has a much wider dynamic expression than a mediocre one; the difference between loud and soft is greater. In addition to having wider dynamic range, musical transients have an increased sense of suddenness, zip, and sharpness of attack. The attack of an acoustic guitar string, for example, is quick, sharp, and vivid. Many mediocre turntables and arms slow these transient signals, making them sound synthetic and lifeless. A good LP front end will also have a coherence that makes the transients sound as if they are all lined up in time with each other. The result is more powerful rhythmic expression.

Just as we want the LP front end to portray the steep attack of a note, we want the note to decay with equal rapidity. A first-rate LP front end is characterized by its ability to clearly articulate each note with a sense of silence between the notes, rather than blurring them together. A good test for an LP front end’s transient characteristics is intricate percussion music. Any blurting of the music’s dynamic structure— attack and decay—will be immediately obvious as a smearing of the sound, lack of immediacy, and the impression that you’re hearing a replica of the instruments rather than the instruments themselves. Hearing live, unamplified musical instruments periodically really sharpens your hearing acuity for judging reproduced sound.

All turntables, tonearms, and cartridges influence the sound’s overall perspective and tonal balance. Even high-quality components can have distinctive sonic signatures. Careful matching is therefore required between the turntable, arm, and cartridge to achieve a musical result. Matching a bright, forward cartridge to an arm with the same characteristics, and mounting both on a somewhat aggressive-sounding turntable, could be a recipe for unmusical sound. Those same individual components may, how ever, be eminently musical when in a mix of components that tend to complement each other.

The very best turntables, tonearms, and cartridges are more sonically neutral than lesser products. System matching is hence less critical as you go up in quality. State-of-the—art turntables and tonearms tend to be so neutral that you can put together nearly any combination and get superlative sound.

You should listen for two other aspects of turntable performance: speed accuracy and speed stability. Speed accuracy is how close the turntable’s speed is compared to 33-1/3 rpm. You need to worry about speed accuracy only if you have absolute pitch (the ability to identify a pitch in isolation). Speed instability, however, is easily audible by anyone, and is particularly annoying. Speed stability is how smoothly the platter rotates. Poor speed stability causes wow and flutter. Wow is a very slow speed variation that shifts the pitch slowly up and down and is most audible on solo piano with sustained notes. Flutter is a rapid speed fluctuation that almost sounds like tremolo. Together, wow and flutter make the sound unstable and blurred rather than solidly anchored. A good turntable with no obvious flutter can still suffer from speed instability. Instead of hearing flutter overtly, you may hear a reduction in timbrel accuracy—an oboe, for example, will sound less like an oboe and more like an undifferentiated tone.