Direct-drive turntable
Encyclopedia
A direct-drive turntable is one of two main phonograph
Phonograph
The phonograph record player, or gramophone is a device introduced in 1877 that has had continued common use for reproducing sound recordings, although when first developed, the phonograph was used to both record and reproduce sounds...

 designs being manufactured today. The other style is the belt-drive turntable
Belt-drive turntable
There are two main types of phonograph turntable drives still being manufactured today, the belt-drive and direct-drive systems; the names are based upon the type of motor system found in each....

. Each name is based upon the type of drive motor used. Both are primarily for playing 12" and 7" vinyl disc records.

Design

In a direct-drive turntable the motor is located directly under the center of the platter and is connected to the platter directly. The first commercially available direct-drive turntable, the model SP-10, was introduced by the Technics
Technics
Technics may refer to:* Technics turntables, no longer in production.* Technics , a brand name of the Panasonic Corporation* An anglicization of the Ancient Greek term techne, used primarily in media theory...

 division of Matsushita in 1969.

Direct-drive turntables may suffer from vibration due to the motor. This is less of an issue for belt-drive turntables. However, in recent years, shock-absorbing (less dense) material, placed between the motor and platter, has been used to cut back on vibrations. The torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

 on direct-drive turntables is usually much higher than on belt drive models. This means the platter speed is less susceptible to outside forces (stylus
Stylus
A stylus is a writing utensil, or a small tool for some other form of marking or shaping, for example in pottery. The word is also used for a computer accessory . It usually refers to a narrow elongated staff, similar to a modern ballpoint pen. Many styli are heavily curved to be held more easily...

, hand). Higher torque also means the platter will accelerate to its proper speed faster so less distortion is heard when the record begins to play.

Some direct-drive turntables further reduce the separation of motor and platter by using the platter itself as the rotor
Rotor (electric)
The rotor is the non-stationary part of a rotary electric motor, electric generator or alternator, which rotates because the wires and magnetic field of the motor are arranged so that a torque is developed about the rotor's axis. In some designs, the rotor can act to serve as the motor's armature,...

 in the turntable's induction motor
Induction motor
An induction or asynchronous motor is a type of AC motor where power is supplied to the rotor by means of electromagnetic induction. These motors are widely used in industrial drives, particularly polyphase induction motors, because they are robust and have no brushes...

. This means that there is no motor, per se, in the turntable - the platter is entirely driven by the magnetic field induced by the turntable's stator
Stator
The stator is the stationary part of a rotor system, found in an electric generator, electric motor and biological rotors.Depending on the configuration of a spinning electromotive device the stator may act as the field magnet, interacting with the armature to create motion, or it may act as the...

.

In all turntables a motor spins a metal disk at a constant speed. On top of the rotating disk (platter) is a mat and on top of the mat records are placed to be played. In the past rubber mats were used to hold the record in place so that it would not rotate independently of the platter. Nowadays slipmat
Slipmat
A slipmat is a circular piece of slippery cloth or synthetic materials disk jockeys place on the turntable platter instead of the traditional rubber mat....

s are used to reduce the friction between the spinning platter and record, and is often made of a felt-like material. This way a DJ can scratch
Scratching
Scratching is a DJ or turntablist technique used to produce distinctive sounds by moving a vinyl record back and forth on a turntable while optionally manipulating the crossfader on a DJ mixer. While scratching is most commonly associated with hip hop music, since the late 1980s, it has been used...

 the record while the platter continues to spin underneath. In direct-drive turntables the slipmat also helps isolate the record from motor vibrations that would be picked up by the stylus.

Many turntables also include a pitch control
Pitch control
A variable speed pitch control is a control on an audio device such as a turntable, tape recorder, or CD player that allows the operator to deviate from a standard speed . The latter term "vari-speed" is more commonly used for tape decks, particularly in the UK...

, for fine tuning to the correct speed, used in conjunction with a strobe light, plus it also allows a DJ to mix
Audio mixing (recorded music)
In audio recording, audio mixing is the process by which multiple recorded sounds are combined into one or more channels, most commonly two-channel stereo. In the process, the source signals' level, frequency content, dynamics, and panoramic position are manipulated and effects such as reverb may...

 using a technique known as beatmatching
Beatmatching
Beatmatching is a disc jockey technique of pitch shifting or timestretching a track to match its tempo to that of the currently playing track e.g. the kicks and snares in two house records hit at the same time when both records are played simultaneously...

. From the late 1990s onwards manufacturers such as Vestax
Vestax
The Vestax Corporation of Japan began in 1977 as a designer and manufacturer of electronic guitars. In the 1980s Vestax introduced a series of cassette based multitracks to challenge established products from Fostex, Yamaha and Tascam's portastudios...

 started to include other electronic controls such as reverse, and "nudge".

DJs and turntablists
Turntablism
Turntablism is the art of manipulating sounds and creating music using phonograph turntables and a DJ mixer.The word 'turntablist' was coined in 1995 by DJ Babu to describe the difference between a DJ who just plays records, and one who performs by touching and moving the records, stylus and mixer...

have learned to use all the above functions to assist them in musical performances.
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