Audeze MM-520

Sources split, though one side is far larger: nearly every reviewer and owner who has listened calls it natural, fuller and more agreeable than the MM-500 — bottom-weighted, mid-forward around 1 kHz, softer through the presence region, several calling it balanced or flat — while forum graph-readers and an MM-500 loyalist who heard it at a meet call it a different, bassier headphone rather than an MM-500 successor, and read the same shape as a 1 kHz bump over under-shot ear gain.

Mostly agreed and mostly praised: SLAM gives the MM-520 a deeper, more grounded, more textured low end than the MM-500 — 'meat on its bones', 'phenomenally tight', subs easy to judge in a mix. The dissents pull in opposite directions, which is why this isn't a clean split: one pro-audio reviewer and an MM-500 loyalist find it bass-predominant or 'bassy', while a German studio reviewer finds the sub-bass comparatively reduced and a consumer-side reviewer finds it tight but short on punch.

“The low-end now has some meat on its bones that the MM-500 lacked.”

Headfonics (Marcus)

“The bass response of the MM 520 may be the best bass I have ever heard on an any headphone under $2000, maybe $2500. It is phenomenally tight and detailed.”

Positive Feedback (Robert H. Levi)

“The MM-520's frequency response is boosted at low frequencies, which are predominant.”

Audiofader (Luca Pilla)

“Allerdings ist der Subbassbereich vergleichsweise reduziert vorhanden, was auf jeden Fall eine Vergleichsabhöre mit regulären Monitoren voraussetzt.”

AMAZONA.de (Axel Ritt) — 'the sub-bass range is comparatively reduced, which definitely calls for cross-checking on regular monitors'

Sources split — this is the MM-520's defining argument. The larger camp, most hands-on reviewers and owners, hears the softened 2–4 kHz region as the fix the MM-500 needed: vocals fuller and less pointed, no shout, easier over long sessions. The smaller camp says the MM-500's midrange was its best asset and the MM-520 gives it away — as a 1 kHz 'honk' over recessed presence (graph-readers), as 'vocals underwater' (an MM-500 loyalist at a meet), or as a flatter, plainer voicing with upper mids so restrained it sounds slightly dull (two editorial voices). Even some happy owners say they miss the old midrange bump.

Sources split, and the split tracks what the listener came from. The larger camp hears a relaxed lower treble — smooth, never sharp, with only a small lift around 10 kHz for air, and to some ears a little rolled-off or dull next to HD 600s, Focals or an LCD-X. The smaller camp hears it as airy, clean and detailed, and owners comparing it with the darker LCD-5s go further: a little bright, even a slight edge in the upper mids and lower treble. Nobody calls it sibilant; the fight is over how much air is left.

Sources split almost evenly, and the split tracks reference frame. Reviewers comparing it with the MM-500 and other Audezes call the stage compact, near-field and 'studio-sized' — organised rather than wide. Reviewers and owners arriving from consumer, closed-back or dynamic headphones call it wide, spacious and, in one pro-audio review, unusually three-dimensional, with height as well as width. Both agree the stage gained depth over the MM-500.

The strongest point of agreement: pinpoint placement, clean separation and layered depth that several sources single out as the MM-520's biggest gain over the MM-500 — 'vastly superior', 'highly localized'. Even the compact-stage camp concedes the imaging inside that stage is exceptional.

“The one difference I was not expecting was the imaging performance from the MM-520. It’s vastly superior to the MM-500.”

Headfonics (Marcus)

“the sound is highly localized with pinpoint positioning”

Major HiFi (Alex Schiffer)

“It’s not a wide sounding headphone, but the imaging especially on the sides are larger and in more detail.”

GoobVibrations210, Head-Fi (owns both MM-500 and MM-520)

Broad agreement on high resolution that stays clear without turning harsh — micro-detail audible at low volume, reverb tails and room ambience exposed, mix flaws revealed. The one relative caveat is the flagship comparison: the LCD-5s still pulls out the last bit of micro-detail.

“Where the Audeze MM-520s leave monitors behind is in the microdetails that can be heard even at low volumes: nothing escapes even at low amplification levels”

Audiofader (Luca Pilla)

“It's remarkable how clear the Audeze MM-520 sounds without ever becoming harsh.”

Notebookcheck (Christian Hintze)

Mostly agreed: SLAM adds weight, tactility and transient snap in the low end — 'punch and weight', 'dramatic power'. A minority hears it as fast and tight rather than hard-hitting, and one German reviewer found his dynamic-driver references (Focal Clear MG Pro, AKG K812) at least as lively. Headfonics adds that the slam scales noticeably with amplifier headroom despite the easy load.

“SLAM makes the headphone much more tactile, and things feel like they have more of an appropriate amount of punch and weight which makes them more engaging and more speaker like.”

GoobVibrations210, Head-Fi (owns both MM-500 and MM-520)

“The mid-bass doesn’t hit you with any great impact, but its transient response is still fast and tight.”

Major HiFi (Alex Schiffer)

Mostly agreed on 'heavy, but wearable': 555 g is 60 g more than the MM-500 and every source names it, yet nearly everyone who wore it reports the thicker memory-foam pads, leather strap and lighter clamp spread the load well — several call it more comfortable than the MM-500 or the LCD-X. The reservations are about long sessions (the weight shows up in the neck after a while), lighter dynamic rivals that are plainly comfier, and fit for big heads: one reviewer ran out of adjustment on a modest head and one owner swapped in Audeze's longer yoke rods.

“Despite the 555g weight, the MM-520 does not present an unmanageable proposition on my head.”

Headfonics (Marcus)

“Thanks to the leather suspension strap beneath the metal headband and the soft ear cushions, however, overall comfort remains excellent.”

Notebookcheck (Christian Hintze)

“The day Audeze manages to make a headphone that sound like the 520's but weighting 150 grams less I will stop looking for perfection, the clamp force is way better on 520 compared to the 500's but I can definitely feel the extra grams.”

RicardoWheelock, Gearspace (mixing engineer, ex-MM-500 owner)

“Auch wenn er hervorragend sitzt, macht sich das Gewicht nach einer gewissen Zeit abhängig von der Nackenmuskulatur schon bemerkbar.”

AMAZONA.de (Axel Ritt) — 'even though it sits superbly, the weight makes itself felt after a while, depending on your neck muscles'

Broadly praised — anodized aluminium and spring steel, a lockable Pelican-style hard case, a quiet braided cable and the magnetically attached pads that every source welcomes as long overdue. The asterisk is the finish: MM-500 owners reported peeling on the rings, Headfonics notes Audeze hasn't said whether the treatment changed, and one reviewer's early MM-520 sample chipped paint on the headband.

“When it comes to build quality, Audeze spares no expense: the housing, headband, and yoke are made of anodized aluminum and spring steel.”

Trance_Gott, Head-Fi showcase review

“The steel headband has the perfect clamping force for my average-sized head, but despite being careful, I noticed the black paint chipping and revealing the metal beneath.”

Irish Examiner (Noel Campion; early review sample)

“There has been no mention of whether the aluminum rings have been treated differently to prevent the peeling that some owners observed over the years.”

Headfonics (Marcus)

Open-back by design — it blocks almost nothing and it leaks. The e-drum reviewer heard every metal cymbal 'clack' through it; an owner reports the bleed is negligible at sensible levels, though not enough to track vocals with a mic in the same room.

“The first caution, as previously mentioned, is the limited sound isolation.”

digitalDrummer (Allan Leibowitz)

“For those worried about bleed from the open backs, if you’re not blasting them, it’s really pretty negligible.”

Devin, Audeze store owner review

Sources split. The larger camp sees a working reference that keeps the MM-500's price while adding SLAM, magnetic pads and better imaging — and, for audiophiles, a 'mini LCD-5s' at well under half the flagship's price. The smaller camp says that cheaper and more comfortable rivals sound as good, that the price only makes sense for people who mix for a living, that $1,699 is a lot for a curve they distrust, and that MM-500 owners have no need to upgrade — a point Marroquin himself makes.