Audeze MM-520 Review: A Professional Open-Back Built for Accuracy

Audeze has built a strong reputation among engineers, producers, and serious listeners for planar magnetic headphones that prioritize accuracy without losing musical engagement. With the Audeze MM-520, the brand continues its Manny Marroquin Signature Series with a professional open-back headphone designed for critical listening, mixing, and studio production. Building on the foundation of the MM-500, the MM-520 introduces updated acoustic technology and a refined reference tuning aimed at delivering better bass control, precise imaging, and reliable detail across the frequency range. For those looking for a studio headphone that combines planar speed with a focused, monitor-like presentation, the MM-520 makes a strong case as one of Audeze’s most practical professional tools.

What You Get

• MM-520 Headphone
• 2.5m (8.2ft) headphone cable
• 3.5mm to 6.3mm adaptor
• Standard Travel Case
• MM-Series Soft Carry Bag

Look & Feel

If you’re familiar with Audeze’s recent crop of headphones, or even the last iteration of this headphone, the MM-500, the MM-520 fits neatly in that catalog in terms of design. Aside from a few minor tweaks, the MM-520 isn’t much of a departure in appearance. The MM-520 adds a similar rim to its ear cups that exists on the LCD-S20 and Maxwell, and the coloration of the aluminum might be a bit lighter this time. Otherwise, the grille pattern, headband, and yokes are all very similar. There’s nothing I would have said needed fixing with the MM-500, especially with how high-grade the materials are.

If you were hoping for something lighter, you might be a bit disappointed, but holding them in my hands and wearing them on my head never gave me the impression that these were that heavy. Of course, this affects comfort level, and thankfully, I think the MM-520 is a suitable headphone to wear for critical listening sessions and studio production. The earpads are thick and plush, made from supgraded memory foam.

Design

The Audeze MM-520 is built around 90mm planar magnetic drivers, using Audeze’s Fluxor magnet array, Ultra-Thin Uniforce diaphragm, Fazor phase management, and SLAM acoustic technology for improved bass definition and spatial accuracy. It comes with a quarter-inch termination and a 3.5mm adapter. A headphone amp is recommended, but if you’re using an audio interface for a smaller studio, that should be efficient enough to drive the MM-520.

Soundstage 

With Audeze’s MM series headphones, you know you’re not getting the most expansive, holographic soundstage. Instead, you’re getting a sound that is engaging in its precision and accuracy. The MM-520’s soundstage takes a bit to show you what it can do with its presentation, but once you start to get a sense of its scope, the way it stacks and folds is incredibly impressive. It never expands too far outward, and you might think the imaging is too centered toward the middle, but the sound is highly localized with pinpoint positioning. Everything is anchored to its carved-out area, still showing dimension with its effective and organized layering.

The way the stereo environment is displayed through the MM-520 is very reminiscent of a pair of studio monitors in a bedroom studio. Spatial imaging is not trying to impress you; it’s trying to be the most efficient reproduction at conveying realistic pan movement for a refined stereo environment. As a result, the MM-520 might come off as too linear for an open-back headphone of this caliber, but as a studio tool, it is exactly what it needs to be.

Low End

A lot has been said about what Audeze’s SLAM technology can add to the bass response, but the MM-520 should make sure it’s all put under control. The MM-520 is exactly that with its bass frequencies. A controlled bass tone that puts just enough emphasis in its sub-bass to give the lows a more solid foundation. It gives the MM-520’s sound profile a believable scale, with detailed rumble that is naturalistic in timbre. Bass clarity is never put into question, as bass strings sustain with a resolving vibration that is apt for critical assessment. The mid-bass doesn’t hit you with any great impact, but its transient response is still fast and tight. Overall, the bass has as much balance as you would expect for a professional studio sound signature, but the SLAM technology allows the sub-bass to express just a bit more gravel for a more engrossing listen.

Mids

Everything is even and breathable in the midrange of the MM-520, as it’s a tuning that should sound familiar for studio gear. Nothing is left in the background, but nothing is excited, leaving the sound signature to lean flat and clinical. There’s still great detail to be found with certain instruments, including string pluck definition and vocal clarity. Distorted electric guitars are even brought to a level that is tightly organized and less chaotic. It shows you how well the MM-520 maintains its frequencies, offering an organized resposne that allows you to assess the midrange without any fogginess. For casual listeners, the MM-520 is still full and defined in its midrange, leaning away from a metallic sound signature but can still be considered a bit plain. There’s no warmth, but the upper-mids have a slight hump for more elevated vocals.

Highs

The treble is surprisingly airy and has some character to it. It’s still a timbre that you can rely upon for pure high-end detail, but its response is in between focused and expansive. The MM-520 finds a good medium to express this flavor of treble, combining airness with tactility in a way that is both informative and satisfying. Its tinge of brightness is elevated by more height, allowing frequencies to ring out naturally without causing fatigue. Reverb tails taper off into a more open space, while crash cymbals crack and dissipate with an inkling of sparkle. Everything is still tidy and even, but the highs on the MM-520 bring more to its reference profile here and have a bit of fun.

Summary

The Audeze MM-520 is not trying to be the biggest or most cinematic open-back headphone in its class. Instead, it succeeds as a focused studio headphone with strong imaging, clean layering, and a balanced sound signature that feels built for precision. Its 90mm planar magnetic drivers deliver tight low-end control, transparent mids, and airy highs, while SLAM technology helps give the bass a more grounded sense of texture without pushing the tuning too far from neutrality. Some listeners may want a wider soundstage or a warmer midrange. Still, for mixing, critical listening, and professional production, the MM-520 offers the disciplined performance that makes it easy to trust. It is another strong entry in Audeze’s MM Series and a worthy option for engineers and audiophiles who value accuracy over exaggeration.

The Audeze MM-520 will be available soon from Audio46.