Audeze’s most accessible closed-back planar aims big with new ‘Slam’ tech

Audeze’s LCD-S20 brings the company’s planar expertise to a more accessible price, mixing premium bass performance, excellent passive isolation and a uniquely dark, weighty tuning that sets it apart from typical closed-back headphones.

Audeze’s new SLAM front-facing bass port helps unlock deeper, tighter low-end performance without unwanted pressure build-up. Picture: Audeze.

After spending several weeks with the Audeze LCD‑S20, I’ve come away impressed by how much refinement, brute force and tonal personality these closed-back planars deliver for the money. They’re not perfect, but they provide a distinctive listening experience that stands apart in a crowded mid-range market.

Design

The LCD-S20 offers a rugged, industrial look with familiar metal yokes and a suspended headband design. Picture: Noel Campion.

I should say I’m already a big fan of the distinctive Audeze sound. I use the LCD-X as my reference headphone, so that’s the baseline I judge everything else against. I was particularly keen to test the LCD-S20 because, when given the choice, I’ll always reach for a wired pair over a wireless one. For travel, office work or gaming, a closed-back design like the S20 gives me the best of both worlds: the superior sound of wired headphones and excellent, if not class-leading, isolation. And at home, things can get noisy, so sometimes I want to shut the world out and enjoy my music without any distractions.

The S20’s design language is immediately familiar. It borrows heavily from the industrial, purposeful aesthetic seen on Audeze’s Maxwell and the MM-series, with a blend of practical plastics, exposed metal forks and a suspension-style synthetic leather strap. While it isn’t the lightest design, the build quality is first-class. The rotating yokes exhibit zero play, and the earcups have that unmistakable Audeze sturdiness, suggesting these will hold up for years of use.

Magnetic ear pads make cleaning and swapping pads incredibly easy while ensuring a perfect seal every time. Picture: Audeze.

The feature I absolutely love is the new magnetic ear pads. This is the first time I’ve seen Audeze use a magnetised mounting system, similar to those on the AirPods Max, on a mainstream model. It’s brilliant: pad swaps are instant, secure and consistent. The polarity prevents incorrect placement, though the pads can be physically fitted backwards, so it’s worth double-checking after cleaning or swapping. The design also incorporates a foam gasket to maintain a proper seal, a crucial factor in the S20's sonic performance.

The cups themselves feature Audeze’s new SLAM technology, which is short for Synthetic Linear Acoustic Modulator. This introduces a cleverly engineered front bass port intended to reduce pressure build-up inside the closed chamber.

Comfort and fit

Comfort is impressive thanks to soft pads and moderate clamping force, making long listening sessions surprisingly effortless. Picture: Noel Campion.

Weighing 563g on my scales without the cable, the S20 are far from light. Much of the weight resides in the earcups, but clamp force is moderate rather than aggressive. I could comfortably wear them for multiple hours without any discomfort, but if you’re used to light plastic headphones, you'll notice the weight.

The headband is adjustable, but not via the usual slider mechanism found on most headphones. You get three discrete sizing positions per side, and while you can mix them asymmetrically, the adjustment range isn’t as broad as some may need. On my head, the fit was secure without squeezing, and I love how the headband strap evenly distributes the weight across my head.

One area where comfort absolutely excels is passive noise isolation. The S20 is impressive, offering one of the quietest passive experiences I’ve encountered on non-ANC headphones. Even with the bass port venting, external noise barely leaks in. For commuting, busy offices or late-night gaming, this is a massive bonus.

Features and specs

The included single-entry cable is flexible and can plug into either earcup. Picture: Noel Campion.

Audeze rates the S20 at 18 ohms with a sensitivity of 93 dB/1mW, a minimum power requirement of over 100 mW, and a recommended power input of more than 250 mW. I had no issues driving them from my MacBook Pro, the Audient ID24 interface, or the Chord Mojo 2. While the laptop could power them easily enough, the two dedicated audio devices have much stronger amplifiers and delivered a fuller, richer and more dynamic presentation of the lossless music I was listening to.

The S20 uses a large 90mm planar magnetic driver, which is considerably bigger than what you’ll find in most closed-back headphones. The benefit of this size is greater control and authority, especially in the low end, where the S20 can dig deep without losing clarity. Audeze rates the frequency response at an impressive 10Hz to 40kHz, giving the headphone plenty of headroom and ensuring it can reproduce subtle details, airy treble and powerful sub-bass with ease. The included cable is long and flexible, and I did not notice any microphonics while using it.

The cable has a 3.5 mm jack, and you can plug it into whichever ear cup is closer to your amp, and the headphones quietly sort out left and right for you. A quality 6.3mm adaptor is included.

Sound quality

With excellent imaging, isolation and cinematic bass, the S20 is a strong choice for entertainment as well as music production. Picture: Noel Campion.

As always, sound is totally subjective, and I don’t claim to be an audiophile. That said, I found the S20’s sound signature is unmistakably Audeze, but with a fresh twist thanks to that new SLAM tech. This headphone is all about authority, bass quality and a dark-tilted warmth that feels intentional rather than accidental.

Thanks to the SLAM port, the sub-bass extension is excellent, with depth and texture that rival far pricier closed-backs. It’s not muddy, slow or over-inflated; instead, it delivers clean, controlled power that elevates everything from hip-hop to cinematic soundtracks. The S20’s ability to thunder without losing composure is noticeable, but those expecting a thumping bass might be disappointed. For me, it’s more about the quality of the bass rather than the quantity, and the S20 delivers on the former.

The mids sound natural overall, with vocals coming through smoothly and without harshness. Treble, however, is noticeably recessed, giving the S20 a darker tone compared to neutral-tuned headphones. If you enjoy a bit of top-end sparkle, you may feel it’s lacking, though a touch of EQ can easily lift the treble to taste. As a closed-back design, the S20 doesn’t offer a large or airy soundstage, so if spaciousness is important to you, something like the MM100 or another open-back model would be a better fit. The presentation here is more intimate, which some listeners will appreciate and others may not.

Overall, the S20 is a non-fatiguing, rich-sounding headphone that you can listen to for hours. If brighter headphones tend to wear you out, the S20’s smoother, darker voicing might be precisely what you’re after.

Verdict

The Audeze LCD‑S20 offers outstanding bass performance, superb isolation and a warm, dark tuning that’s both distinctive and engaging. Not for bright-treble fans, but an excellent choice for those seeking richness, comfort and serious low-frequency authority.

€599 richersounds.ie