A turntable stylus reads the grooves in a vinyl record. The stylus, or needle, vibrates as it tracks the grooves. The vibrations are carried through a small metal rod to the inside of the cartridge containing a moving magnet or coil. An electrical signal is induced by the movement of the magnet or coil, which is then passed to metal pins on the back of the cartridge. Wires inside the tonearm of the turntable send the audio signal to the preamp, which you then connect to your receiver or amplifier.
Understanding the Components
So how does a turntable stylus work? First, you should understand the main components that hold the stylus:
- Head shell
The tone arm is the metal arm that holds the cartridge containing the stylus. A counterweight is placed on the other end of the arm to adjust the weight of the stylus as it tracks the grooves. A head shell is attached to the end of the arm that holds the cartridge. The head shell is typically plastic and often compatible with a wide range of cartridges.
The cartridge houses the components responsible for picking up and creating an audio signal. The stylus, which is also called a stylus tip or needle, is attached to a metal rod called a cantilever. The cantilever extends from the inside of the cartridge, where it is attached to a magnet or a coil of wire, depending on the type of cartridge. Cartridges consist of either a moving magnet or moving coil.
How Is the Signal Picked up?
Whether you play a 7-inch or 12-inch vinyl, the record contains one long groove that spirals from the outside to the center of the record. The grooves usually measure just 0.04mm to 0.08mm wide. Each side of the groove contains tiny wavy lines. The lines on the outer edge of the groove represent the right-channel audio while the lines on the inner edge represent the left-channel audio.
As the stylus tracks the groove, the tiny little waves on the edges of the groove create movement. The movement is carried from the stylus tip to the moving magnet (MM) or moving coil (MC) through the cantilever. With an MM cartridge, the magnet moves, which transduces an electrical signal that is sent to the coil. With an MC cartridge, the magnet is fixed in place and the coil moves.
The electrical voltage that is created by this process carries the right and left audio signals. However, the signal is still too weak for a typical amplifier or receiver to play the audio. To boost the signal, the audio is sent to the “phono stage.” The signal is amplified and then sent to the phono outputs on the back of the turntable. Your amplifier, pre-amp, or receiver then plays the audio through your speakers.
Stylus Tips and Shapes
As we have written earlier, the material for a proper stylus is always diamond. But did you know that there are two main types of stylus tips — nude diamond tip and diamond tip. A nude diamond tip is simply a diamond bonded directly to the cantilever. The diamond tip stylus consists of a diamond in a metal shank and is often found in cheaper cartridges. It weighs more compared to nude diamond tips, which limits its accuracy.
There are also different shapes:
- Spherical: most affordable and durable
- Elliptical: greater accuracy and less durable
- Hyper elliptical: better sound quality and expensive
- Micro-ridge: the most accurate and expensive stylus shape
As the tip becomes more pointed, it can track the grooves with greater accuracy. However, the sharper tip also causes the stylus to wear faster, read more hear on how long a stylus can last. Based on this information, you should hopefully find it easier to choose your next stylus tip.