This past weekend I acquired a new-to-me NAD 1600 preamplifier that I would soon use with my vintage, yet seemingly indestructible Sanyo TP-825D turntable. After making all of the initial connections and cuing up Sting’s “The Dream of Blue Turtles” LP, I encountered a distinct popping noise when the snare drum was introduced in “If You Love Somebody Set Them Free”. Admittedly, I hadn’t used the turntable in a while, and seeing as how it was my maiden attempt at creating sound through the preamp, the possible causes initially seemed limitless. At first I figured it might have been poor cartridge alignment, though I soon ruled that out. Then I started to consider the NAD had some electrical issues. Luckily, before long, it dawned on me that the preamp wasn’t at all broken, but its phono setting was switched to MC instead of MM.
After a sigh of relief and quick pat on the back, I detailed the horrifying encounter to a friend of mine who asked “What is MM and MC?”. And that comment, my vinyl-loving friends, inspired this very article.
It’s quite true that vinyl is one of those hobbies that can be appreciated on many levels. You have those who choose to completely immerse themselves in the craft, as well as others who prefer to simply drop whatever needle comes on their factory-preset deck. But anyone who sticks with it long enough will sooner or later discover that a turntable’s cartridge is just as important to the overall sound quality of your audio system as location is to real estate. And on that note, I’d like to quickly explain why the cartridge is such a vital element in the equation.
Most audio enthusiasts already realize transducers are the most difficult component in a sound system to design correctly. Transducers being those components that convert one form of energy into another. With most modern audio systems, the speakers are the only transducers, converting electrical signals into mechanical vibrations that send waves of beautiful atmosphere crashing into our ears, which some people like to call music. This is why many audiophiles agree that speakers are the most important element in their system. But when it comes to vinyl, your cartridge is another transducer, doing the exact opposite job of the speakers, by converting mechanical vibrations that the needle picks up from the record groove into an accurate electrical signal that can be amplified and later re-converted by the speakers.
And now for the good stuff…
The difference between a moving magnet (MM) and a moving coil (MC) cartridge is rather simple. With an MM, magnets are connected to the stylus in close proximity to a fixed coil that converts the vibration into an electrical system. But with an MC cartridge, it’s the coil that is attached to the needle, while the magnets are stationary. So both styles rely on the same basic components (magnets and coils) to generate the electrical current, but are arranged in different configurations. And it’s that arrangement that makes all the difference.
Magnets are relatively heavy when compared to the coils, but are much more stable due to their solid construction, so mounting the magnets (instead of the coil) to the stylus provides for greater durability. However, the weight of the magnets prevents the stylus from vibrating as freely, and therefore MM carts offer slower response than MC models.
Whether you choose a moving magnet or moving coil cartridge will depend on your budget as well as application. If you’re a DJ, I’d highly recommend the more durable construction of a MM. Not only are replacement cartridges more wallet-friendly, but when playing through a PA system, audiophile quality isn’t a major concern.
However, if you’re a stickler for great sound, then saving up for a more sensitive MC cart is highly recommended. But please note that typically MC cartridges produce a small fraction of the signal that MM’s create. So if you decide to go with MC, either be sure that your preamp has an MC setting (like the NAD 1600 mentioned above), or invest in a high output model cart.
Feel free to ask questions or share your comments below. We’re all here to learn.