Of all the components in a DJ's kit, we probably understand turntable cartridges the least. We know they traverse the groove of a record and help turn it into sound, but most of us haven't thought much about how they do it or what makes one better than another. It's not especially clear what "better" even means in this context: is it good sound, solid grip on the groove, low wear-and-tear, or something only an audiophile would really care about? For many DJs, if you put the needle on the record and hear sound it's serving its purpose.

It makes sense that your choice of cartridge would be an important one, though—they're the point of contact between your record collection and the soundsystem. Mess something up at that stage, and it'll be messed up at each point down the line, not least when the music hits the crowd's ears. Anything that makes such intimate contact with your records has the potential to damage them, either with one gnarly gash or subtly over time. And even those who don't know about the principles of phonography are probably aware that not all needles can withstand even light cueing, let alone beatmatching or scratching.

If you've peeked into a DJ booth in the last ten years, you've almost certainly seen an Ortofon Concorde headshell extending from a Technics 1200's tonearm like a anteater's nose. There's certainly an argument to be made that the Danish brand has captured the standard (for house and techno mixing, at least) with a product that's easy to install and looks good to boot. Like plenty of other bedroom jocks, I'd seen them in clubs, bought a pair and used them religiously for years.

Then in 2012, while taping a Critics Roundtable in Berlin that featured a segment on mastering, I met Christoph Grote-Beverborg, AKA CGB, an engineer at Berlin's famed Dubplates & Mastering studio. During the segment, he called out Ortofons as inferior needles—"Really the worst DJ pickups ever built in this planet" is how he put it at the time—and mentioned Shure's M44-7 cartridge as a better bet for DJs. After the taping, we did an A/B test between Ortofon's Concorde DJ S and a vintage Shure cartridge Grote-Beverborg had brought with him. The difference was stark enough that I ordered a pair of M44-7s as soon as I got home.

I was reminded of our meeting recently when Grote-Beverborg surfaced in the comments of the Industry Standards piece on Technics 1200s, offering a half-dozen or so technical details about the turntables that hadn't made it into the piece. I had shortlisted the Shure pickups for this feature due to their punchy sound signature, resurgence of popularity in dance music (Pinch and DJ Hell are fans) and longevity (like many of the other gear featured, they've gone unchanged for ages)—but knew I needed to know more about what was happening under the hood to argue for them as the standard over something that fits on a Concorde headshell. If anyone could nitpick on this topic, it was him.

That's how I found myself sitting across from Grote-Beverborg in the lobby of Dubplates & Mastering, learning about effective mass, tonearm geometry and high-versus-low compliance. His perspective is a valuable one—a veteran studio hand, live sound engineer and DJ, he joined D&M in 1996 and has mastered and cut a staggering number of records since. (His Discogs profile is 36 pages long, to give you some idea.) There aren't many people who know (and care) more about what happens when needle touches wax, and I couldn't imagine I'd find anyone more outspoken on the topic. What I got was less a full-throated endorsement for any one product—he softened his stance on the Ortofons, in fact, specifying that they're "the worst in the relation of quality to price." Instead, he gave a thorough explanation of what makes a DJ cartridge a DJ cartridge, and why the M44-7 fits the bill better than most.

Shure, an American audio company who in the 1950s were among the first to make cartridges capable of playing stereo records, markets the M44-7s as needles "engineered for scratch DJs and turntablists," with "ultra high" skip resistance and output levels and "ultra low" record wear. Grote-Beverborg says they predate hip-hop by a few decades, though—check out an early product announcement in Billboard to get a sense of their age—and bear much similarity to broadcast cartridges. "You see the classic cartridges from EMT and Denon, for example, from even the '50s or so and later—they have the same design principles as the modern day DJ cartridges. [The designers said,] OK, first thing: the needle mustn't skip, never ever, so you have to put a lot of weight on it. And at radio stations, you had to back-cue, because they were looking for the start on the record." Grote-Beverborg says hip-hop DJs had been using lesser Shure and Stanton needles until the company redeveloped the M44-7 and began marketing it to turntablist crews in the '80s.

Grote-Beverborg, who was DJing hip-hop in the '80s before moving into jungle, drum & bass and reggae, starting bringing his own needles out after being left high-and-dry with a broken house cartridge at an early gig. This is how he discovered the sonic pleasures of the M44-7. "I mounted the first Shure while his record was playing, and then I hit the crossfader—boooom, big sound, much bigger than the Concorde." Its insanely high output seemed to be what kept the cartridge alive during vinyl's darkest days in the '00s, when their flood of signal helped vinyl emulation software like Serato and Traktor accurately read timecode off control records.

Hefty levels don't mean great sound—achieving them requires bigger magnets and increased moving mass, which Grote-Beverborg describes as a detriment to sound quality. You also run the risk of overloading your amp and distorting the signal. But there's more to M44-7s than their boooom. What I first noticed about Shure M44-7s when I started using them was that they made records sound warm, punchy and physical—like dance 12-inches should, basically. My Ortofons may have sounded subtler, but rather than lend more detail, they had a kind of clinical sheen. Why cart around all that weight if you're going to miss what makes them so pleasing to the ears?

"It has better sound, to be honest," Grote-Beverborg said of the M44-7 cartridge over Ortofons. "It has better low-range, it has better high-range, it has better stereo image." He described a number of other problems he's identified with Concordes as well. They don't exactly fit the standard interchangeable headshell mount that you find on 1200s, he says, which can cause dropouts. Overhang, or the distance beyond the center of the platter where the stylus sits when you pull the tonearm over the diameter, is also irregular on Concordes and can result in tracking distortion. (Unless you used the oft-lost plastic overhang gauge that came with brand-new 1200s, you've probably got your M44-7s set up wrong, too. The point is that with a cartridge you mount on the headshell yourself, there's the possibility of getting it just right.)

None of which is to say that the M44-7 is the world's best-sounding pickup. Any DJ cartridge, Grote-Beverborg explains, is a compromise, because much of what lets the stylus take the kind of abuse that comes with cueing, backspinning and scratching is at odds with what would make them sound great. As the stylus moves through the groove, it traces a path that takes it up, down and side-to-side. In a "moving magnet" design like the M44-7, the stylus is connected by a cantilever system to a magnet that moves through a metal coil; as the magnet moves, it produces a voltage analogous to the groove of the record, which your DJ mixer amplifies and your speakers convert to sound. ("Moving coil" designs reduce moving mass—and thus let the stylus move more freely—by having the cantilever push a spring that moves along a magnet. The tradeoff, though, is levels so low that a DJ mixer might not be able to amplify them enough for nightclubs.)

For the most accurate reproduction, you'd want a stylus that could trace the subtleties of the groove as precisely as possible. When you're talking about cantilever suspension, the technical term for this is compliance, where high compliance means a more freely moving cantilever and low compliance means a stiffer one. Unfortunately, a high-compliance cartridge, which would make more subtle movements than a low-compliance one, will never survive a back-cue. "Turn it back two centimeters or three," Grote-Beverborg says, and "you can throw it in the bin."

The stylus shape itself also bears on playback. Hi-fi needles are elliptical or hyper-elliptical, with the thin ends in contact with the groove. This design gives the stylus access to the subtlest modulations in the cut, but if there's anything off with the alignment, it can cause distortion, imaging issues and uneven wear between stereo channels. A spherical stylus like the one on the M44-7 might miss some nuance, especially in the high frequencies. "If you have the big, chunky spherical stylus," Grote-Beverborg explains, "it can't go into the tiny curvatures of the groove. It just rubs along." But the fact that it sits in the groove more or less the same, whether or not the cartridge is perfectly aligned, makes it a way less risky proposition, both for the physical well-being of your records and for the overall accuracy of playback.

Grote-Beverborg emphasizes that these design considerations will make your decks sound far from sweet. "If you are sitting at home, and you have a good stereo system and a good listening room, and you have, say, a well mastered CD and the same as a vinyl, and you play the CD, and then you play it with a Shure or a Concorde—" He pauses for a second to consider. "I mean, it also depends on the music. If we are talking about drum & bass, or like classical, or an acoustic jazz piece—for the latter two, you would probably like the CD more. But if you put on a good hi-fi stylus, you will love the record more. It's a big, big, big difference, if you have these very high-compliance cartridges."

He makes a critical point about it "depending on the music." Club soundsystems aren't necessarily tuned to emphasize subtlety, so the best cartridge may not, either. What an M44-7 lacks in definition in the highs helps lend drum-machine cymbals some extra bite. And the bit of compression the cartridge gives to the bass helps it pop. Hard Wax, the iconic Berlin record store affiliated with Dubplates & Mastering, uses nothing but M44-7s at their listening stations, and you'd guess that they've chosen them not just for their low wear-and-tear on their stock, but because they present the shop's techno records as they were meant to be heard: big, heavy and perfectly nasty.

That a cartridge dealing with such a difficult task could produce a sound that's actually favorable in the club could be a happy accident. But Grote-Beverborg seems genuinely impressed with a design that manages to balance ruggedness and imperviousness to skipping with its own kind of musicality. I ask if he has a sense for how the designers did it, and it's the only time in our chat he seems remotely at a loss. "I think it's the cleverly designed cantilever, that they just got the compliance and everything right. I am not so deep into this. This is, like, really serious engineering stuff."