Topics: Phono Cartridges and Needles

Major Types of Cartridges

Cheap

Most new turntables are shipped with inexpensive cartridges, to keep the price of the turntable down.  Mass-market cartridge manufacturers offer low-price cartridges to penetrate every segment of the market.  Any cartridge with a spherical or conical cartridge should be replaced for the sake of minimizing wear on the record grooves, as well as better sound quality.  Cheaper needles contact the groove wall along a very small surface area, resulting in greater contact pressure and a stronger tendency to blast away (ablate) small bits of vinyl as the pressure is removed, much as road pavement will erupt from the surface on very hot days because the thermal expansion cannot be resolved in any other way.

Audiophile

A broad definition of the term “audiophile” includes any cartridge that’s designed to play music accurately.  They feature better quality elliptical or linear contact styli, cantilevers that are light and stiff; and coil wires of high quality.  The price range is very wide, from less than a hundred dollars up to a thousand or more.

Moving Magnet

The vast majority of cartridges on the market are Moving Magnet cartridges.  They vary greatly in quality and price, but from an electronic point of view, they are all interchangeable.  Their output levels vary slightly (between 3 and 5 millivolts), but the resistive and capacitive loads required by them are identical.  If your old cartridge has a broken or worn needle, you do not have to replace the original stylus, or obtain the same model of cartridge.  However there are three fitment styles: half-inch, p-mount and DJ.  P-mount cartridges do come with half-inch mount adapters.  If your tonearm has a headshell with two slots, one half inch apart, to accept mounting screws, then it’s a half-inch system.  The p-mount system has a rectangular opening at the end of the tonearm, plus a finger rest.  The cartridge plugs in to the end of the tonearm and is held in place by a single machine screw and nut.  Finally, there are DJ cartridges, which have the finger rest built in to the cartridge; they plug in to the round end of the tonearm in place of the H-4 headshell, and are held in place by a round collar.

The best type of cartridge mounting system is the half-inch mount, for a few reasons.  The first is that the mounting position is adjustable.  The cartridge can be moved back and forth in the slots, to adjust the effective length, and twisted left or right, to set angular alignment.  When aligning the cartridge for 12 inch records, you will want to loosen the mounting screws enough to allow the cartridge’s position to be moved, and then use our alignment tool to set its position in the headshell.  You can also custom-align the cartridge for 10 inch or 7 inch records, which will require the cartridge to move back about a third of an inch from the correct position for 12 inch record alignment, and rotate outwards a few degrees.  This is only possible with a half-inch mount system.

The second reason half-inch mounting systems are preferred is that most cartridges are half-inch mount, and p-mount cartridges come with half-inch adapters.  Also, p-mount cartridges usually come with lower-quality needles; only a few have elliptical needles, which are substantially better than low-cost spherical or conical needles.

DJ Cartridges

DJ cartridges are definitely not preferred for straight playback.  They are designed for cutting and scratching, backcueing and the like.  They’re supposed to avoid skipping in a throbbing loud club environment, with the turntable and platter being constantly disrupted.  They do this with very high tracking weights, usually 3 to 5 grams.  They also run lower quality needles than audiophile cartridges.  Unless you are going to use your turntable as a nightclub DJ, mixing new beats, your records and your ears will be much happier with an audiophile (straight playback) cartridge.

Moving Coil

Personally I wouldn’t spend more than a couple hundred dollars on a cartridge unless it’s a moving coil cartridge. These produce much higher responsiveness because of the lower mass at the end of the cantilever. However they also produce much lower signal strengths, and require an additional stage of amplification before the phono stage. They also have different requirements for resistive and capacitive loads, for which a proper preamp would have adjustments available.

Needles (Styli)

Look for the quality of the needle first. Spherical and conical needles meet the groove wall on a very small surface area, creating high contact pressures and damage to the groove wall. They’re also not as responsive. Elliptical needles are the least that I would consider using or selling, but they vary in size. Typically their needles have sizes from 0.4 to 0.2 mils wide, and 0.7 mils long. Smaller is better; they reach deeper into the groove and meet on a larger surface area. The more exotic needles, such as linear contact, are better yet, and for the same reasons.

The other differences between moving magnet cartridges have to do with channel separation; this measurement relates to the quality of the magnetics and the resistance to signals being read by the opposite coil. The better ones have tighter tolerances between the moving magnet and the coil in the cartridge body. Better cartridges also have cantilevers that are lighter and stiffer.
Within the audiophile-quality cartridges, differences get smaller as prices get higher; an economist would call it declining marginal returns.
Also, investing more money in cartridges shouldn’t be pursued until other issues on the turntable have been addressed, such as vibration damping, cartridge alignment, anti-skate adjustment and platter speed stability.