Comparing Moving Magnet and Moving Coil Phono Cartridge Types

So you want to set up a turntable to best match your audio preferences, collection of vinyl, and personal budget. How do you choose between moving magnet and moving coil phono cartridge types? The two have different designs and performance characteristics, despite achieving the exact same function of creating audio from a vinyl record's intricate grooves.

It all starts with the stylus (also known as a "needle") on the phono cartridge. The stylus travels through the record's grooves, moving horizontally and vertically as it tracks the minute fluctuations within the surface; this is how music is represented on vinyl. As it navigates the path, the stylus converts mechanical energy into electric energy. This small audio signal is generated by the proximity of a magnet and a coil, and that audio signal is sent through the wires leading to your home stereo equipment or speakers. All turntable phono cartridges have magnets and coils. The main difference is where they are located with respect to the stylus.

Moving Magnet Cartridge

A moving magnet (MM) cartridge is the most common type of phono cartridge. It has two magnets on the end of the stylus—one for each channel—located inside of the cartridge itself. As the stylus moves, the magnets change their relationship with the coils in the body of the cartridge, which generates a small voltage.

One of the advantages of a moving magnet cartridge is high-output delivery, which typically means it is compatible with almost any phono input on a stereo component. Many moving magnet cartridges also feature a removable and replaceable stylus, which can be important and convenient in the event of breakage or normal wear. It generally costs less to replace a stylus than the entire cartridge itself.

One of the disadvantages of using a moving magnet cartridge is that the magnets tend to have higher weight and mass when compared to that of a moving coil cartridge. This greater value generally means that the stylus can't move as quickly over the record, which inhibits its ability to track the subtle changes within the groove's surface. In this respect, a moving coil cartridge has a performance advantage.

Moving Coil Cartridge

A moving coil (MC) cartridge is, in a way, the opposite of a moving magnet cartridge. Instead of connecting magnets to the end of the stylus within the cartridge body, two small coils are used instead. The coils are smaller than their magnet counterparts and weigh much less, giving the stylus more agility when navigating the constantly changing record grooves. In general, moving coil cartridges can trace surfaces better due to the lower mass, which results in greater detail, improved accuracy, and less distortion of sound.

One disadvantage of using a moving coil cartridge is that it generates a smaller voltage, so the MC cartridge quite often requires a secondary preamplifier (sometimes known as a head amp). The head amp increases the voltage enough to be picked up by a phono input on a stereo component. Some moving coil cartridges have a higher output and are compatible with a standard phono input, although the output tends to be somewhat lower than that of a moving magnet cartridge.

Users cannot remove the stylus on a moving coil cartridge. As a result, in situations where the stylus has worn out or broken, it would be up to the manufacturer to replace or repair the part. If not, then the entire cartridge must be discarded, and a new one has to be purchased and installed.

Which One to Choose?

Both moving magnet and moving coil cartridges provide great performance and are offered in a range of prices, shapes, sizes, and levels of quality. People looking to achieve the best overall sound for turntables often choose the moving coil cartridge. However, the make and model of your turntable are the most important factors. Most turntables are compatible with only one or the other cartridge type. Some can use either kind. If you're unsure, a quick peek into the turntable's product manual will let you know which type is needed when it comes time for you to choose your next turntable cartridge (or stylus) replacement.