Record Players Explained for the Streaming Generation

How do you consume your music, these days? Aside from on the radio, that is. Do you play MP3 or other files on your phone and computer, or perhaps do you stream from an online service? If you’re really at the cutting edge though you’ll do none of those things, because you’ll be playing it on vinyl.

The legendary Technics SL1200 direct-drive turntable, as used by countless DJs. Dydric [CC BY-SA 2.5)], via Wikimedia Commons.
The legendary Technics SL1200 direct-drive turntable, as used by countless DJs. Photo by Dydric CC-BY-SA 2.5

A few years ago reporting on a resurgence of sales of vinyl records was something you would never have expected to see, but consumer tastes are unpredictable. Our red-trousered and extravagantly bearded hipster friends have rediscovered the glories of the format, and as a result it’s popping up everywhere. For those of us who are old enough to have genuinely been into the format before it was cool again, the sight of Sergeant Pepper and Led Zeppelin II on 12″ at outrageous prices on a stand at the local supermarket is a source of amusement. It’s good to see your first love back in vogue again, but is it really the £20($25) per album kind of good?

With the turntable having disappeared as an integral part of the typical hi-fi setup the new vinyl enthusiast is faced with a poor choice of equipment. Often the best available without spending serious money at an audiophile store is a USB device with the cheapest possible manufacture, from which the playback will be mediocre at best. We’ve lost the body of collective knowledge about what makes a good turntable to almost thirty years of CDs and MP3s, so perhaps it’s time for a quick primer.

If you talk to a certain type of audiophile you will encounter a barrage of myth and pseudoscience on almost any topic relating to audio, and vinyl is no exception. It’s simplest for the purposes of this article to say that it is possible to play back a vinyl record such as to achieve a very high standard of audio reproduction given good quality equipment, and leave it at that. We’re not going to descend into audiophile fantasy, nor are we going to wax lyrical about turntables that will cost you more than your car. Instead we’re going to look at what makes a turntable, and hopefully help you pick one which will neither damage your records or sound bad.

How Vinyl Recordings Work

Close-up magnification of a 45RPM vinyl record, showing the audio waveform in each groove. The red lines are 1mm apart. Alex:D [Public domain], via Wikimedia Commons.
Close-up magnification of a 45RPM vinyl record, showing the audio waveform in each groove. The red lines are 1mm apart. Public domain photo by Alex:D.

There was a time when describing the operation of a record player would have been unnecessary as they were ubiquitous, but we want this to be a primer to serve all generations so it’s worth a quick diversion.

A record is a thin plastic disc into the surface of which is cut a spiral groove. Analogue audio is expressed as variations in the wall of the groove, and played back through a needle being placed in the groove and held stationary as the record is rotated anticlockwise on a turntable.

The vibrations of the needle are converted into electrical audio signals which are amplified for your hi-fi system. The discs hold recordings on both sides, and can be found in 12″, 10″, and 7″ variants. Long-playing albums typically require a rotation speed or 33⅓ RPM, while singles usually rotate at 45RPM. You’ll also see reference to earlier 78RPM records and rare 16RPM talking book records, but they are out of the scope of this article.

The groove itself would originally have carried mono audio, but later recordings were adapted for stereo by expressing the right and left channels in its opposing walls. An equalisation curve is applied to the audio before recording in the vinyl, this reduces the bass and thus the area taken up by the groove and the chance of the needle jumping out of it. A corresponding reverse curve must be applied in your playback device’s preamplifier, this is referred to as the RIAA curve after the industry organisation that specified it. The best visualization we’ve ever see for these grooves is with an electron microscope; and amazing trick performed by Ben Krasnow.

A youthful rite of passage for hackers of old was to play music from a record with a piece of paper inserted into the split end of a sharpened matchstick that formed the needle, this serves to demonstrate how accessible and simple this technology can be. Despite this simplicity though, to achieve good playback results you’ll need something a little better. We’ll now go through the individual components of your record player, describe their operation and varieties, and help you spot the good and the bad.

The Platter And Drive

A substantial aluminium platter on a belt drive turntable, with its mat removed.
A substantial aluminium platter on a belt drive turntable, with its mat removed.

It’s easy to describe the complete device you’ll play back your vinyl on as a turntable, without considering the turntable itself as an important component. We’ll now take a minute to look at it, and split it into its components: platter, bearing, and drive system.

The platter provides the circular flat surface upon which the record sits as it rotates. It will often have a rubber or similar mat on top of it to provide an acceptable surface to avoid damaging the record. The job of the platter is to rotate without vibration or flexing, so a good platter should be rigid, greater than the size of a 12″ record, and have a significant mass. You’ll see them most frequently as aluminium castings, though high-end turntables have been made of a wide variety of materials. By contrast cheap turntables almost always have lightweight plastic platters that provide no damping, and easily warp.

Jockey wheel drive on an ancient and rather grubby 1950s turntable.
Jockey wheel drive on an ancient and rather grubby 1950s turntable.

The bearing at the centre of the platter has the job of allowing rotation to continue without excess friction or vibration. There are platters that float on a layer of oil, spin on ball bearings, rest on a tapered spindle, and more. Cheap plastic platters will often have minimal attention to this important component, instead simply resting at the bottom of the spindle and relying on the friction between plastic and metal being low enough that the drive system can overcome it.

To rotate, the platter must have a drive system, and this is often touted as a marketing feature of the complete turntable. The drive does not have to be particularly powerful except in special applications such as DJ turntables, it simply has to be as smooth and vibration-free as possible and rotate the platter at the correct speed. Ancient turntables may have a jockey-wheel drive against a rim on the underside of the platter, but you’ll want to look for either a belt drive or a direct drive. Belt drives as their name suggest insulate the platter from vibrations through a rubber belt, while direct drives couple the platter directly to the shaft of a motor.

The belt-drive mechanism in close-up. The lever on the left changes speed by shifting the belt between different widths of the motor spindle.
The belt-drive mechanism in close-up. The lever on the left changes speed by shifting the belt between different widths of the motor spindle.

The choice of motor on a turntable is important, for through the motor comes most of the vibration that can affect playback. Look for twin-pole AC motors in a belt-drive turntable, and avoid shaded-pole motors. Very cheap plastic belt drive turntables often have small and vibration-happy DC motors.

Direct drive motors by comparison will often have the rotor magnets fixed in a ring on the underside of the platter, locating over a ring of stator electromagnets on the turntable chassis. They will be driven by a multiphase AC supply in a similar manner to a stepper motor, and the quality of both motor and drive will depend on the price of the unit. The legendary Technics SL1200 series turntables as used by countless DJs use this arrangement, though it’s arguable whether or not their high cost owes more to the legend than the reality.

The Tonearm

The tonearm takes the form of a balanced arm on a pivot that carries the cartridge and needle assembly over the record, and has to ensure that the correct forces are exerted on the record by the needle. Too much force either downwards or sideways will compromise playback quality and damage both record and needle.

The tonearm fulcrum, showing typical tracking weight and anti-skate adjustments.
The tonearm fulcrum, showing typical tracking weight and anti-skate adjustments.

A tonearm should have two accessible adjustments, tracking weight and anti-skate force. The tracking weight and anti-skate force settings should be defined by the manufacturer of your cartridge and needle, and will be specified in grammes. Cheap turntables will have these preset by the manufacturer or may miss them entirely, their presence is a good indication that the turntable is of some level of quality.

The tracking weight is simply the weight exerted by the needle on the record, and it will normally be in the region of a gramme or so. In most cases it is set by means of a counterweight on the other end of the tonearm that can be moved back and forth on a screw thread. There should be a dial on the counterweight calibrated in grammes. To set the tracking weight, first adjust the weight until the tonearm balances on the level, then adjust the weight back until the required tracking weight setting is shown on the dial.

The anti-skate force is a force applied to the tonearm that pulls it towards the edge of the record. This counteracts the force applied to the tonearm towards the centre of the record by the friction of the disc, with the desired result of reducing groove wear. There is usually a spring that is tightened or loosened by means of a small calibrated knob, simply turn to the value in grammes.

The tonearm itself can be found in a variety of different shapes, both straight and curved. It should be a metal tonearm, avoid turntables with plastic tonearms as a tonearm should be as rigid as possible. There are a lot of audiophile theories about the perfect shape for a tonearm, but the idea is to ensure that the cartridge axis is always at right angles to the groove and that the arc it tracks is as good an approximation to a straight line as possible. You’ll find hotly contested arguments over straight tonearms versus S-shaped ones, but you are probably better placed concerning yourself with your tonearm’s quality than its shape.

The Cartridge And Needle

An Ortofon moving-magnet cartridge in its removable headshell.
An Ortofon moving-magnet cartridge in its removable headshell.

The business end of a turntable is a tiny diamond needle that sits in the groove on the record, and transmits the vibrations up its mounting arm to a cartridge. The cartridge converts these vibrations into electrical impulses, which are sent down the wires to your RIAA preamp — the “Phono” input on your amplifier. On some turntables the cartridge sits in a removable headshell rather than being attached directly to the end of the tonearm.

You will see three types of cartridge, in ascending order of quality of price: ceramic, moving magnet, and moving coil. Ceramic cartridges use a piece of piezoelectric ceramic to generate the audio signal and are typically found on cheap turntables, while most reasonable quality cartridges will be moving magnet designs in which a tiny magnet vibrates within a coil of wire. High-end audiophiles will probably go for moving-coil designs in which the magnet stays stationary and the coil vibrates.

As long as the needle is not worn or damaged, and the tonearm adjustments have been made correctly, it should not matter in terms other than audio quality which type of cartridge you use. However you do not have to descend into audiophile silliness to find a decent moving-magnet cartridge to be a better choice than a ceramic one.

Mounting The Turntable

If you’ve made it this far you’ll have gained an understanding that vibration is the chief enemy of the turntable owner. We’ve talked about vibration from the drive system, but what about that from the environment?

There was a time when a cheap “Music centre” hi-fi would have a plastic turntable moulded into its top. It would be an integral part of the unit, and any vibrations in the surrounding environment from traffic or passers-by would find their way directly to the needle. Thus you had to tread carefully, or else the record would skip and jump.

Higher quality turntables will thus incorporate some form of spring and damper system, with the aim of removing these vibrations before they can affect playback. Typically this will mean a set of springs preloaded by the mass of the turntable, but you may find elaborate oil-filled damper systems as well. You will need to ensure that your turntable incorporates some kind of suspension.

So… What Should I Look For?

If you’ve read the advice above, you should now have some idea of what makes a decent turntable. You are looking for rigid components and as vibration free a design as possible, a rigid platter with some mass coupled to a belt or direct drive, with a good quality metal tonearm and a moving-magnet cartridge. If you consult your favourite hi-fi store you’ll find these attributes aplenty in new turntables, but you should expect to pay at least a three-figure sum for them. Avoid plastic turntables at all cost, and pass over the cheap turntables designed primarily for recording your LPs through USB.

If you can’t afford a new turntable, what are your options? There are many decades’ worth of secondhand audiophile turntables out there and you can find bargains, however beware that you’re not paying over the odds for something where a new equivalent would be a better bet. If you’re really strapped for cash though, hit the want ads and the thrift stores. Or ask your older relatives whether their 1970s hi-fi is still gathering dust in the loft. Often the turntable supplied with decent quality mass-market hi-fi systems in the 1970s was surprisingly well-made, and a bit of legwork can still land you one of these unloved and overlooked units for very little money indeed. The turntable in most of the photos on this page for example is an unremarkable JVC turntable from the 1970s with a 2-pole AC motor and a hefty aluminium platter, picked up for a song a few years ago in a junk shop.

It’s important to remember with analogue audio that the most important link in the chain is the first one. Put a bit of effort into sourcing a turntable, and it will reward you.

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