How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want an open, airy, long-session home listening headphone with two cables in the box and a velour comfort story, choose Sennheiser HD 599; if you need a closed, isolating, foldable work headphone built for tracking and travel, choose Austrian Audio Hi-X20.
• Sennheiser HD 599 — biggest strength: open-back, around-ear design with 38 mm dynamic drivers, a wide 12 Hz–38,500 Hz range, plush velour cushions and a padded headband for hours of relaxed listening.
• Sennheiser HD 599 — biggest trade-off: the open back means almost no isolation, and the 50 ohm impedance plus 6.35 mm cable bias it toward a desk setup rather than a noisy commute.
• Austrian Audio Hi-X20 — biggest strength: closed-back cups with 44 mm Hi-X drivers, 25 ohm impedance, folding/swiveling earcups, replaceable memory foam pads and a detachable 3 m cable for studio and portable work.
• Austrian Audio Hi-X20 — biggest trade-off: closed-back isolation comes with a narrower 12 Hz–24 kHz range and a heavier 400 g build, so it’s more of a tool than a lounge chair.
• Pick the HD 599 if you listen at home, want the spacious open sound and prioritize comfort above all.
• Pick the Hi-X20 if you record, mix, or need to block out a room and want a headphone that folds into a bag.
The HD 599 is the headphone you buy when the goal is easy, unhurried listening. It's an around-ear, open-back design with 38 mm dynamic drivers, a 50 ohm impedance and a sensitivity of 106 dB, and Sennheiser's E.A.R. acoustic design is aimed at a naturally balanced tone with strong spatial presentation. That "open" character is the whole point: because the cups aren't sealed, sound leaks in and out, which is exactly what gives the HD 599 its wide, speaker-like feel. In my opinion, that openness is what makes long evening listening sessions so pleasant, and it's also what makes this headphone the wrong choice for a train, a shared office, or anywhere you need to disappear into your own bubble.
Buy the HD 599 if you listen at a desk or on a couch, you value an airy soundstage and velour comfort, and you don't need isolation at all. The two detachable cables make it flexible in a specific way: a 3 m cable with a 6.35 mm jack for a home entertainment system or amp, and a shorter 1.2 m cable with a 3.5 mm plug for phones, tablets and laptops. Skip it if your listening happens in noisy places, if you need to keep sound from leaking out around other people, or if you want a headphone that folds down and disappears into a bag.
Austrian Audio Hi-X20: Who It's For
The Hi-X20 is the opposite philosophy, and it's proud of it. This is a closed-back, over-ear headphone with 44 mm Hi-X (High Excursion) drivers, a 25 ohm impedance and a 12 Hz–24 kHz range. Austrian Audio describes the tuning as balanced mids and highs with clear bass and very low noise at all frequencies — language that points to a precise, analytical presentation rather than a warm, forgiving one. That's the profile a recording, mixing or mastering session actually wants: you hear what's on the track, including the parts you'd rather not.
The practical design details are where the Hi-X20 earns its keep. The earcups fold and swivel, the cable detaches, and the ear pads are replaceable memory foam — three things that matter if the headphone lives in a bag or on a stand and gets used daily. There's a metal frame for stability, and the package includes a 1/4-inch plug adapter and a carry bag. The cable is 3 m and terminates in a 3.5 mm jack, so it works with a laptop or interface directly and with studio gear via the included adapter. Sound isolation, not passive cancellation, is the noise-control approach here, which is simply what a closed back does.
Buy the Hi-X20 if you record or produce, if you need to block out a room and keep your audio to yourself, or if you want a wired headphone that survives being folded up and carried around. Be aware of the trade-offs: at 400 g it's noticeably heavier than the Sennheiser, and closed-back isolation always narrows the sense of space compared with an open design. If your only use is relaxed listening in a quiet room, the Hi-X20 is more headphone than that job requires — and it costs you the openness the HD 599 is built around.
• Best for open, spacious sound → Sennheiser HD 599. The open-back design is the single clearest difference between these two.
• Best for isolation and recording → Austrian Audio Hi-X20. Closed cups and sound isolation make it the only sensible pick for tracking, monitoring or noisy rooms.
• Best for long comfort sessions → Sennheiser HD 599. Velour cushions, a padded headband and 9.17 ounces versus 400 g.
• Best for portability → Austrian Audio Hi-X20. Folding, swiveling earcups, a detachable cable and a carry bag.
• Best for easy amplification → Austrian Audio Hi-X20. At 25 ohm it's the lower-impedance, more forgiving load; the HD 599 sits at 50 ohm.
• Best for wide frequency extension on paper → Sennheiser HD 599. 12 Hz–38,500 Hz versus 12 Hz–24 kHz.
• Best for servicing over time → Austrian Audio Hi-X20. Replaceable memory foam ear pads and a detachable cable are real longevity features.
• Best for a home entertainment system → Sennheiser HD 599. The 3 m cable with a 6.35 mm jack is made for exactly that.
If I had to pick one, I'd buy the Austrian Audio Hi-X20. In my opinion it's the more versatile headphone: closed-back isolation, a low 25 ohm impedance that plays nicely with laptops and phones, folding earcups, replaceable pads and a detachable cable cover studio work, travel and everyday listening in one package. The HD 599 is the better pure listening experience in a quiet room, and if that's all you do, it's the more enjoyable headphone. But as a single do-everything wired pair, the Hi-X20 wins on flexibility, and flexibility is what most people actually need.
The Hi-X20. It's a closed-back design with 44 mm Hi-X drivers, 25 ohm impedance and a detachable cable, all of which suit recording and monitoring. The HD 599 is open-back, so it leaks sound both ways and isn't built for tracking.
Not meaningfully. It relies on passive noise cancellation and an open-back design, so you'll hear the room and the room will hear you. If isolation matters, the Hi-X20's closed cups are the right tool.
The HD 599, on paper. Velour ear cushions, a padded headband and a 9.17-ounce weight favor it. The Hi-X20 uses memory foam pads that are replaceable and comfortable, but at 400 g it's the heavier headphone.
The HD 599, at 12 Hz–38,500 Hz versus the Hi-X20's 12 Hz–24 kHz. That's a spec difference, not a verdict — the Hi-X20's 44 mm Hi-X drivers are tuned for precise, low-distortion monitoring rather than maximum extension.
I don't quote prices here because they change constantly. Use the "Check latest price on Amazon" button on this page to see the current figures for both before you decide.
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.