How turntables work

McIntosh MT2 coming soon!

McIntosh MT2 coming soon!

At one level, for a turntable to work, it’s a very simple process.You take a record, place it on a surface, put a needle of some kind through a piece of paper to hold it steady and act as a speaker, then spin the record. If the needle sits in the groove, you’ll hear what’s on the disk. If you want it to sound good however, you have to go to a lot more trouble.

A turntable, more than any other piece of AV equipment, is an instrument which plays music. It interacts with the record, another physical item. It’s a mechanical device, operating either on a belt drive (most consumer models), or a direct drive unit (usually DJ models). This assembly turns a platter, which holds the record.

The tone arm holds a cartridge with a needle suspended from a cantilevered support. It rests suspended, almost floating, above the spinning disk, vibrating against the grooves, transmitting the vibrations of the needle to the device, to the amp, to the speakers. The physical responsiveness of each component contributes to the quality of the presented sound.

Instructables Paper Turntable by Plugable

Instructables Paper Turntable by Plugable

 

Records and record players/turntables are fundamentally different from downloads or CDs and the playback devices that interpret digital signals. Digital playback devices can play anything from the bass note of a big mechanical organ pedal to a sustained soprano vibrato with equal ease. It’s all the same. Just playing a file.

For a turntable to play the deep bass organ note however, that wave is a huge swelling wave. Then to play the soprano vibrato, it requires the accurate rendition of teeny tiny waves back and forth, back and forth, back and forth. it’s a lot harder to pick all of that up without jumping out of the groove or distorting.

A record player is made up of many delicate moving parts. These precisely balanced components work together to reproduce the sound stored in the grooves of the vinyl disks. The tone arm supports the cartridge holding the needle at the correct level of pressure (tracking force), to play the rotating record while remaining properly nested in the grooves, while vibrating along with the notches in the grooves. That vibration reproduces the stored sound.

A few practical things to consider about turntables:

Speeds
Most turntables are set up to play both 45rpm and 33 1/3rpm records by default. Some turntables that don’t play 78s out of the box can have a pulley change. The 78 records will need a different stylus however.

Belt drive vs direct drive
For the home market, the belt drive provides shock absorption against any vibration transfer from the motor to the platter and helps eliminate any “notchiness” in the sound.

There was a popularity of direct drive consumer models in the 80s, but today most consumer models are belt-driven and the direct drive turntables are generally the choice of DJs. Advantages for DJs are lots of torque, giving an extremely accurate speed, which is quickly achieved when the table is started, drawbacks include cogging issues and notchiness.

Cartridge
Turntables up to a certain level come with a cartridge installed. Usually it’s a name brand, but a basic model. Often they’re pre-set up for that cartridge, occasionally you have to make adjustments. Sometimes people will upgrade and improve the cartridge, generally they won’t.

Two or three years after they buy it, they may replace only the stylus (needle). On the other hand, ¾ of the price of the cartridge is the stylus. A $100 cartridge generally comes with $75 stylus. As a result, often people will usually take that opportunity to upgrade the cartridge as well.

Cover
Your turntable may have a dustcover to prevent dust from accumulating on the turntable and any record left on it when not in use. The dustcover serves no function when you are playing records. If your turntable has a hinged dust cover, be sure it is down while the disks are playing to prevent vibration.

Size
A lot of the audiophile turntables have a base much larger than you are accustomed to seeing. Mainstream turntables are usually 13” x 13”, or 14” x 14”, while an audiophile turntable might be 18” x 18” or 19” x 19”. This larger base accommodates a longer arm, which has certain benefits.

For some people, turntables are an interesting addition to their equipment, and allow an opportunity to play records they were bequeathed or collected on a whim. For others it is an opportunity to hear some rare music only available on vintage disks. Among either group, there are many who feel the analogue sound experience has greater warmth.

Come to Liptons to see and hear music played on a range of turntables and discuss the merits of each with our professional sound experts.

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