Alnico vs Neodymium Cartridge Magnets: Which Is Better?

What the Magnet Does in a Phono Cartridge

The magnet inside a phono cartridge creates the magnetic field that, along with the coils, generates the tiny electrical signal when the stylus moves through a record groove. The magnet's strength, shape, and placement directly affect the cartridge's output, damping, and tonal balance.

In a moving magnet (MM) cartridge, the magnet is attached to the cantilever and moves between fixed coils. In a moving coil (MC) cartridge, the magnet is fixed and the coils move. The choice of magnet material influences both designs, but the overall cartridge engineering often matters more than the material alone. A well-executed design with a modest magnet can outperform a poorly engineered one with an exotic magnet.

Alnico: The Classic Magnet

Alnico is a traditional magnet alloy made from aluminum, nickel, and cobalt. It has been used in audio transducers for decades and is still appreciated for its smooth, musical sound. Alnico magnets are usually larger than neodymium magnets for a given field strength, which can add weight and affect cartridge shape.

Because alnico has a lower magnetic energy product than neodymium, cartridge designers may use a larger magnet to achieve the desired output. This can influence the cartridge's moving mass and compliance. Many listeners describe alnico cartridges as warmer and more forgiving, though this is a subjective impression. The increased mass can also lower the resonant frequency, which might interact with tonearm damping.

Alnico's lower coercivity means it is more susceptible to demagnetization if exposed to strong opposing fields, but in normal use it remains stable. It is still favored in many high-end designs for its reputed tonal character.

Neodymium: The Modern Workhorse

Neodymium is a rare-earth magnet that provides a very strong magnetic field in a small package. This allows cartridge manufacturers to build compact, low-mass cartridges with high output potential. Neodymium magnets are also more resistant to demagnetization than alnico.

The higher magnetic field can produce a hotter output voltage, which may be beneficial if your phono stage has limited gain. However, output is determined by the entire magnetic circuit and coil design, so a neodymium cartridge is not automatically louder than an alnico one. A designer might use fewer coil windings to reduce inductance, which can improve high-frequency response.

Neodymium's strength also allows for stronger magnetic damping, which can tighten bass and control stylus vibrations more effectively. This can be an advantage in heavy tracking cartridges or when using a higher-mass tonearm.

Output, Damping, and Tonal Balance

Magnet strength influences electromagnetic damping, the force that controls the stylus's movement and helps define frequency response. A stronger magnet generally provides stiffer damping, which can tighten bass and reduce resonance, while a softer magnet might yield a more relaxed, rolled-off treble.

Tonal balance is not dictated solely by the magnet. The stylus shape, cantilever material, and suspension design also shape the sound. For example, a cartridge with an advanced stylus shape can resolve more detail than a cheap one, regardless of magnet type. You can learn more about cartridge stylus shapes comparison.

When comparing cartridges, look at the whole package: output voltage, compliance, recommended tracking force, and the phono stage's input specs. Learn more about cartridge output voltage and phono preamp gain to tune your system.

Electromagnetic damping also affects how the cartridge interacts with the tonearm. A higher-damping cartridge may pair better with a low-mass tonearm, while a lower-damping cartridge might suit a high-mass arm. This is where system matching becomes critical.

Matching the Magnet to Your System

Your phono stage's gain and input capacitance play a role. A neodymium cartridge with higher output may saturate a high-gain phono stage, while an alnico cartridge might need more gain. Check your phono stage's specifications and compare with the cartridge's output voltage.

The cartridge's compliance must match your tonearm's effective mass. A high-compliance cartridge with a soft magnet (like some alnicos) may work better with a low-mass tonearm, while a low-compliance cartridge with strong neodymium might suit a high-mass arm. See our cartridge compliance match and tonearm effective mass guides for details.

If you are unsure, consult your turntable's manual or the cartridge manufacturer's recommended tracking force and compliance values. A good match minimizes resonance and tracking errors. For turntable buyers, consider the cartridge that comes pre-installed and whether it can be upgraded later.

Which Magnet Should You Choose?

There is no universal winner. Alnico cartridges often appeal to listeners who want a vintage, musical character, while neodymium cartridges may suit those who want higher output and a tighter bottom end. Your phono stage's gain and your speakers' sensitivity also matter.

If you already own a turntable, focus on matching the cartridge to your tonearm's effective mass and compliance. A mismatch can cause tracking issues regardless of magnet type. For new turntable buyers, consider the overall package and the cartridge's reputation.

Listen to a variety of cartridges if possible. The magnet material is only one aspect of the sound. The stylus profile, cantilever material, and generator design all contribute. A well-regarded cartridge with an alnico magnet might outperform a cheap neodymium cartridge, and vice versa.

Care and Handling Considerations

Cartridge magnets are strong. When handling a cartridge, keep it away from ferrous tools and magnetic surfaces that could attract it and cause damage. The Library of Congress advises keeping audio materials away from strong magnetic fields, which includes loudspeaker magnets and motor transformers.

Proper record care is also important. Wash and dry your hands before playing records, handle them by the edges and label, and store them upright. These practices protect both the vinyl and the stylus.

If you are replacing a stylus or cartridge, follow the manufacturer's instructions and avoid touching the stylus tip. For more, see our guide on how to replace a turntable stylus and cartridge stylus life.

What to pick for your use

Questions

Is a neodymium cartridge always louder than an alnico one?

Not necessarily. Output depends on the number of coil windings, the magnetic circuit, and the cartridge type. Neodymium's stronger field can allow higher output, but designers might trade that for other goals.

Can I upgrade my cartridge from alnico to neodymium?

You can change cartridges, but the magnet material is part of the cartridge design. Swapping to a different cartridge changes the entire electrical and mechanical assembly. You must match the new cartridge to your tonearm's mass and compliance.

Are alnico magnets fragile?

Alnico is sensitive to demagnetization from strong opposing magnetic fields, but in normal use it is stable. Avoid placing the cartridge near strong magnets or transformers.

Does magnet type affect the sound more than stylus shape?

The stylus shape has a major impact on tracking and frequency response. Magnet material influences output and damping, but the stylus, cantilever, and suspension are equally important.

What about moving coil cartridges?

Moving coil cartridges use a fixed magnet; the type of magnet can affect the output level and damping. Some MC designs use neodymium for higher output or smaller size, but many use other materials.

How do I know which magnet material my cartridge uses?

Many manufacturers state the magnet type in the specifications or marketing materials. If not, you can contact the manufacturer or look for teardown reviews, but be aware that internal parts may vary between manufacturing runs.