Vinyl records have made a comeback in recent years, and with that comes the need for quality turntable equipment.
One essential component of a turntable is the phono cartridge, which reads the grooves on a record and turns them into audio signals.
Among the different types of phono cartridges available, the dual moving magnet (DMM) cartridge is a popular choice for its high-output delivery and compatibility with almost any phono input on a stereo component.
But what exactly is a DMM cartridge, and how does it work?
In this article, we’ll dive into the details of this type of cartridge and explore its advantages and disadvantages.
So sit back, relax, and let’s explore the world of DMM phono cartridges.
What Is A Dual Moving Magnet Phono Cartridge
A dual moving magnet (DMM) phono cartridge is a type of cartridge that uses two magnets on the end of the stylus to generate a small voltage as it moves along the grooves of a vinyl record. This voltage is then sent to a phono preamp or phono input on a stereo component for amplification and equalization.
The DMM cartridge is called “dual” because it has two magnets, one for each channel, located inside the cartridge itself. This design allows for high-output delivery, which means it can work with almost any phono input on a stereo component.
The magnets in a DMM cartridge are attached to the internal end of the cantilever, which is the part of the cartridge that holds the stylus. As the stylus moves along the grooves of the record, it puts the whole cantilever/magnet assembly into motion. The motion of the magnets occurs near fixed electrical coils, which creates an electrical signal that is sent down the tonearm wires and out to the phono preamp.
One advantage of using a DMM cartridge is its high-output delivery, which means it can work with almost any phono input on a stereo component. Additionally, many DMM cartridges 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.
However, one disadvantage of using a DMM cartridge is that the magnets tend to have higher weight and mass compared to that of a moving coil cartridge. This greater weight can inhibit its ability to track subtle changes within the groove’s surface, which can affect its overall performance.
What Is A Phono Cartridge?
A phono cartridge is a device that is used to convert the grooves on a vinyl record into electrical signals. It is also known as a turntable cartridge, magnetic cartridge, or moving coil cartridge. The phono cartridge is attached to the end of the tonearm and contains a small magnet, wire coils, and a needle tipped with diamond or another precious stone.
There are two main types of phono cartridges: moving magnet (MM) and moving coil (MC). The MM cartridge has two magnets on the end of the stylus, one for each channel, located inside of the cartridge itself. As the stylus moves along the grooves of the record, the magnets change their relationship with the coils in the body of the cartridge, which generates a small voltage. This type of cartridge has a high-output delivery, which means it is compatible with almost any phono input on a stereo component. On the other hand, MC cartridges have two coils that are attached to the upper end of the cantilever. They move in the air gap of a fixed permanent magnet according to the oscillations of the stylus. These coils are much smaller than on an MM cartridge and offer finer and more precise tracking, resulting in a wider frequency response and more detailed sound reproduction.
Phono cartridges can be made from many different materials, from plastic and metal to hardwood and precious stones. The quality of the cartridge can reflect the expense of the rest of the turntable. A higher-end turntable will likely have a cartridge made of teak, mixed metal, or even gold, while a less specialized turntable will have a cartridge made of aluminum, plastic, or particle wood.
The Difference Between Moving Magnet And Moving Coil Cartridges
When it comes to phono cartridges, there are two main types: moving magnet (MM) and moving coil (MC). The main difference between the two types of cartridges is in how they function mechanically.
A moving magnet cartridge has static coils and a moving magnet, while a moving coil cartridge has a magnet that stays still while the coils vibrate. Moving coil cartridges are generally lighter than moving magnet cartridges, which makes them more precise and capable of creating a more delicate sound. However, they are also more complex and difficult to maintain, requiring the expertise of a professional.
Moving magnet designs are heavier than moving coil setups and exhibit greater inertia when it comes to reading the subtle changes within the grooves. This means that MM designs are less competent at tracking very high-frequency content, and therefore some listeners may feel they lack transient detail.
In terms of cost, moving coil cartridges tend to be more expensive than moving magnet cartridges. This is because they are more delicate and sensitive, requiring more specialized manufacturing techniques and materials. Additionally, they are more expensive to maintain due to their fragile nature and the need for professional attention if something goes wrong.
What Is A Dual Moving Magnet (DMM) Cartridge?
A dual moving magnet (DMM) cartridge is a type of phono cartridge that uses two magnets on the end of the stylus to generate a small voltage as it moves along the grooves of a vinyl record. The DMM cartridge is called “dual” because it has two magnets, one for each channel, located inside the cartridge itself.
The DMM cartridge works by attaching the magnets to the internal end of the cantilever, which holds the stylus. As the stylus moves along the grooves of the record, it puts the whole cantilever/magnet assembly into motion. The motion of the magnets occurs near fixed electrical coils, which creates an electrical signal that is sent down the tonearm wires and out to the phono preamp.
One advantage of using a DMM cartridge is its high-output delivery, which means it can work with almost any phono input on a stereo component. Additionally, many DMM cartridges 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.
However, one disadvantage of using a DMM cartridge is that the magnets tend to have higher weight and mass compared to that of a moving coil cartridge. This greater weight can inhibit its ability to track subtle changes within the groove’s surface, which can affect its overall performance.
How Does A DMM Cartridge Work?
A DMM cartridge achieves energy conversion by connecting the vibrating cantilever to a set of magnets that vibrate in close proximity to a pair of coiled wires. The tiny magnets, positioned between the two coils, vibrate and produce a small electrical current as they move along the grooves of the record. This current is then sent down the tonearm wires, out the turntable, and over to the phono preamp for proper amplification and equalization.
The DMM cartridge design is simpler to execute in production, thus they tend to be more affordable and have user-replaceable styli. This means that in the event of breakage or normal wear, it generally costs less to replace a stylus than the entire cartridge itself.
Advantages Of Using A DMM Cartridge
There are several advantages to using a DMM cartridge for your vinyl record playback needs. Firstly, the high-output delivery of the DMM cartridge allows it to work with almost any phono input on a stereo component. This means that you don’t have to worry about compatibility issues when using a DMM cartridge with your existing stereo system.
Secondly, many DMM cartridges feature a removable and replaceable stylus. This can be particularly convenient in the event of breakage or normal wear and tear. Instead of having to replace the entire cartridge, you can simply replace the stylus, which is generally less expensive.
Another advantage of using a DMM cartridge is its ability to accurately reproduce low-frequency sounds. The dual magnets in the cartridge provide a strong magnetic field, which helps to maintain consistent tracking and reduce distortion in the low-frequency range.
Finally, DMM cartridges tend to be more affordable than other types of cartridges, such as moving coil cartridges. This makes them a great option for those who are looking for high-quality sound without breaking the bank.
Disadvantages Of Using A DMM Cartridge
Despite its advantages, a DMM cartridge also has some disadvantages. One of the main drawbacks is that the magnets in a DMM cartridge tend to be heavier and bulkier than those found in moving coil cartridges. This added weight can lead to a reduction in tracking ability, which can negatively impact the sound quality of the playback.
Another disadvantage of using a DMM cartridge is that it may not be as accurate or stable as other types of cartridges. While it may be suitable for general radio work, it may not provide the precise voltage measurements needed for more specialized applications.
Finally, while many DMM cartridges feature replaceable styli, they still require regular maintenance and cleaning to ensure optimal performance. Failure to properly care for a DMM cartridge can result in premature wear and tear, leading to a decrease in sound quality and overall lifespan.
