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As promised, it’s finally time that I start writing a new audio guide series. The previous one was about collecting vinyl records, now it’s time for the record players, i.e. turntables.

Every turntable consists of a base, a motor, a platter with a spindle, signal cables, a tonearm and a cartridge with a needle. They can also be full of additional useful mechanisms and control functions. There are also different methods of operating a turntable. The components of a turntable also require maintenance and sometimes even replacement. The goal behind this guide series is to showcase and explain all the different aspects of owning, using and keeping our turntable (and at the same time our vinyl records) in best shape.

In this part I’ll focus on explaining all the different types of turntables and turntable drives…

1. Basic types of turntables

The type of the turntable is determined by the way in which it can be operated by the user.

a) Manual

In a manual turntable, all functions must be done manually by the user. In most cases, you will find only the most important switches on your manual turntable, that is the cue button/lever (you use it to put the arm/cartridge over or onto the record or the so called “armrest”) and the playing speed control. Most manual turntables operate as follows:

In order to start playing a record, you have to put the tonearm in cue, manually move the tonearm so that the needle is above the desired point on the record from which you’d like to start playing it and then lowering it onto the record by disengaging the cue. The turntable’s motor should engage in the moment the arm’s over the turntable platter.

If you wish to stop playing, you have to put the arm in cue again and move it back to the armrest and then disengage the cue. The motor will disengage the moment the arm leaves the space over the platter.

Also, when the record side that you’re playing comes to an end, you’ll have to manually stop it as described above. If not then the motor will keep running and the needle will stay on the record’s inner empty grooves.

Some older manual turntables also have start/stop buttons which are used to start or stop the turntable motor. Such turntables won’t automatically engage or disengage the motor depending on the arm’s position.

Most modern and expensive “audiophile” turntables are manual ones.

b) Semi-automatic

Semi-automatic turntables operate similarly to the manual ones, except for one difference. Such turntables have a built-in automatic mechanism that enables them to do one of the following tasks when the played record side comes to an end:

- disengage the motor,
- put the arm in cue over the end of the record, then disengage the motor,
- put the arm in cue, move it automatically back to the arm rest, disengage the cue and then disengage the motor.

You can find the first two automatic shutdown function variants mostly in older (60’s and prior) semi-automatic turntables. Most of the newer ones employ the last, full-cycle shutdown function, also known as the auto-return.

Some semi-automatic also have a stop button, which enables us to engage the auto-return function at any time while the record’s playing.

Most turntables that you may find will be semi-automatic.

c) Automatic

Automatic turntables work like semi-automatic ones with the auto-return function, but they can also automatically start playing the record.

On such turntables there’s always a start and stop button. The stop button works like the one we may find on a semi-automatic turntable. The start button on the other hand engages the automatic start mechanism, which works in such a way that it starts the motor, puts the tonearm in cue, moves it automatically over the beginning of the record and then disengages the cue, after which the record starts playing.

Early automatic turntables had the auto-start mechanism coupled with the playing speed control. It was done so, because back then 12” LPs were played only with the 33 rpm speed setting, while 7” singles had to be played under 45 rpm. Because the playing speed was directly in relation with the record’s size, the auto-start mechanism was set so that, depending on the set playing speed, it would move the tonearm onto the appropriate beginning of a single or LP.

Later, record companies began to publish so called “Maxi singles” (which had the size of an LP, but played under the 45 rpm speed), EPs (10” records) and 7” singles that played under 33 rpm.

It became obvious to turntable companies that coupling the auto-start mechanism with the speed control wouldn’t make much sense from now on, so they started to put record size controls next to the speed controls, with which you could set the size of the played record, so that the auto-start mechanism would know where the actual beginning of the record is.

On most automatic turntables, the start button can be also used to automatically stop playing and start playing the record side from the beginning.

Automatic turntables can also have an auto-repeat function. It works in such a way that after the auto-return mechanism kicks in, the auto-start function starts, so the record side can be played continuously. In such a case, even pushing the stop button or even trying to manually stop the record won’t help. You need to turn the repeat function off in order to shutdown the turntable. Some turntable brands like Technics have used more sophisticated auto-repeat mechanisms in some of their automatic turntables, in which you could define the number of repetitions (in most cases up to 5 or 6) or set it to a continuous playing loop.

2. Other turntable types

There are also several other, more exotic types of turntables. Those worth mentioning are:

a) Tangential/Linear turntables

Such turntables are automatic and in most cases controlled by a microprocessor. The tonearm in such a turntable is not placed under an angle like in regular turntables. It’s a straight arm with a moving base located in the rear of the turntable, which has it’s own separate motor. It works in such a way that the tonearm and it’s base moves across the record in a linear fashion, just like the record’s master disc has been cut in the manufacturing plant (some people say that they sound better just because of that).

Tangential turntables operate just like automatic turntables, except that you can’t manually move the tonearm. It is done by special buttons which control the position of the tonearm (you use them to move the arm left or right over the record).

b) Programmable turntables

These are very rare and expensive 80’s machines. They employed a special tonearm and cartridge which had a small laser on it. The laser was used by the turntable to see how many tracks are on the record’s side and where are the track gaps located.

Thanks to that, one could use such a turntable like a CD player, by selecting the track from which it should start playing or even program the order of tracks in which the record should be played.

c) Record changers

Those were turntables which worked similarly to a jukebox. They were special automatic units which had a special long spindle on which you could stack up to 4, 5 or 6 records. The turntable would then play them one at a time (only the sides that were pointed upwards, of course) and shut itself down.

Most record changers could also be used like normal, single-record turntables.

3. Turntable drive systems

There are 3 common types of turntable drive. All of them use some kind of speed regulating mechanism (in order to keep the playing speed as constant as possible) about which I’ll write in one of the next parts of this guide series.

a) Belt-Drive

The most basic turntable drive. It uses a low-speed motor with a pulley on it. A rubber belt goes around the motor pulley and the outer or inner rim of the lower portion of the platter. Thanks to that the motor’s torque is transferred to the platter.

The advantage of such a drive is that it’s quiet and the motor doesn’t have any acoustic impact on the turntable’s audio output signal.

The weakness main is that the rubber belt deteriorates over time or from heavy-duty use and needs to be replaced.

Most modern “audiophile” turntables are belt-driven.

b) Idler wheel-drive

This turntable drive system can be usually found in record changers. It uses a high-speed motor with a stepped pulley on it. A so called idler wheel moves on the inner rim of the platter and the motor pulley, thus putting the platter into motion.

c) Direct-drive

The most sophisticated type of drive, invented by Technics. It uses an electronically controlled motor, which sits directly under the platter and moves the spindle on which the platter resides.

The main advantage of such a drive system is that it rarely needs any maintenance and the doesn’t have any parts which you’d need to eventually replace over time. It also guarantees precise and stable platter rotation.

The biggest disadvantage of a using such a drive is that if poorly engineered, the motor can become a source of acoustic feedback on the turntable’s audio output signal.

In the 80’s, the market became flooded with cheap Japanese direct-drive models, which used poor components and were of poor design. Because of that, most people (even today) tagged the direct-drives as being always of lower quality than belt and idle wheel drives. That’s not entirely true, because a properly designed quality direct-drive (for example a Dual 701/721 or a top-of-the-line Technics, like the famed 1200/1210 series) can surpass in quality most other turntables.

Every DJ turntable uses a direct-drive.

That’s all for now. Stay tuned for the next installment of the “Turntable 101″ post series. I also plan to make a “Glossary” page in which you will find definitions of the most common technical terms used while talking about audio components.

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