How does a Turntable Work ?

Curious about how Turntables give you such rich sound?

A turntable is a device that rotates a vinyl record at a constant speed while cueing, playing, and stopping the record. This is the part of the player that actually plays the music, with the stylus being dragged across the grooves by an arm with a counterweight. Turntables usually require an external amplifier and speakers to play music, although some models include built-in speakers.

There are three main parts to any record player: the platter, the tonearm, and the cartridge. While these components may seem self-explanatory, they all play an integral role in transforming the vibrations created by your record into an electrical signal that can be amplified.

Tonearm - The tonearm is the pivoting arm that holds the cartridge and stylus (needle) in place.

Cartridge - The cartridge is the part that holds the stylus in place. The cartridge converts vibrations into electrical signals, which are then converted into sound by your receiver or amplifier.

Phono preamp - A phono preamp boosts a very low-level signal to line level so it can be played through speakers or headphones without an external receiver or amplifier. You might see these referred to as "phono stage" or "phono EQ."

Platter - The platter is where you place your record before playing it. It's usually heavy and made out of either metal or wood for better stability. Some turntables have direct-drive platters with a motor underneath, whereas others have belt-drive platters with a belt connecting the motor to the platter itself. Belt-drive tables tend to be slightly more expensive, but some users prefer them for their quieter operation and potential for better sound quality. Belt-driven turntables also have an advantage over direct-drive ones because the belt's elasticity reduces vibration from the motor being transmitted to the platter and stylus assembly, which could cause skipping.

Pitch control - Also known as tempo, pitch control helps you decide the RPM or the speed at which the record rotates. Generally, LPs play at 45 RPM or 33 1/3 RPM. Some record players also support 78 RPM.

What makes the Turntable Turn?

The Heart of the turntable is its motor drive system. It’s the motor that spins the platter and the record. Different turntables spin the platter in one of the three ways, using an Idler wheel, a Belt and Pulley system, or having the motor attached directly on the platter called Direct Drive. Depending on your record, The platter spins at either 33, 45 or 78 rpm. Most of the turntables available today are belt driven. Belt driven turntables have the advantage of isolating motor humming and vibration.  But overtime the belts start to become loose. Direct drive and Idler drive give instant torque, but idlers too wear out over time. Direct drive turntables have a very long life and are desired by audiophiles and DJ’s.

What makes the Sound then?

 

 

 

When the record is spinning, the diamond tip or the stylus, contacts the groves of the record and starts to vibrate. This in turn vibrates a magnet attached at the end of the stylus. Next to the Moving Magnet is a coil. The vibrating magnet induces a small current in the coil. This current is then sent through the wires to the amplifier to be amplified. This is the case in a moving magnet cartridge. In a moving coil magnet, it is the coil that vibrates and created electric signal and the magnets are stationary. It is important that the stylus just touches the record grooves, too much pressure and the record will get scratched, too little pressure and the stylus will skip grooves which damages both the record and the stylus. The tonearm helps with this.

 

What does the Tonearm do?

  

The Tonearm is where the Cartridge is mounted, and the wires coming out of it directed towards the back of the turntable. It also controls the tracking force i.e., the weight with which the stylus moves along the record groves. This is usually set to 5 grams by adjusting Balancing weight at the end of the Tonearm. Some tonearms also feature further adjustments like anti-skate and a cueing lever which lifts and lowers the cartridge safely. Turntables which have automatic operation, feature a tonearm which lifts itself and places the cartridge along the grove when the record starts playing and lifts the cartridge and places itself back on its rest when the record has ended. Another hidden role of the tonearm is providing grounding to the cartridge to eliminate humming.

All these Parts come together to reproduce the amazing warm sound of a vinyl record that we all know and love.

 


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