22 Apr Beyerdynamic DT 900 Pro X: The Headphones Producers Love

Posted at 18:16h in Exclusive, Exclusive, Gear & Tech, Review, Review by Elias Kollböck

▶ 5:17 Reading time

I placed the Beyerdynamic DT 900 Pro X over my ears and hit play on Bonobo’s “Kerala.” After thirty seconds, I stopped the track and started again from the beginning—not because anything was wrong, but because I’d heard details I’d missed after a hundred listens with other headphones. A shaker track in the rear left. A spatial echo that builds gradually. That’s the moment you understand why open-back headphones exist.

TECH SPECS

▸ Beyerdynamic DT 900 Pro X: open-back circumaural, 48 Ohm, STELLAR.45 drivers, from 219 Euro
▸ Made in Germany. Handcrafted in Heilbronn. Not a marketing gimmick—just fact
▸ 48 Ohm: works with smartphones, laptops, DACs. No headphone amp required
▸ Frequency response: 5–40,000 Hz. Wider than most competitors
▸ Comparison: AKG K712 Pro (from 267 Euro, 62 Ohm) and Sennheiser HD 600 (from 294 Euro, 300 Ohm)

What “open-back” means for headphones

Open-back headphones feature perforated earcups. Sound gets in, sound gets out. That might sound like a drawback, but it’s anything but. This open design creates a soundstage—where instruments aren’t trapped inside your head but surround you instead. A sense of space that closed-back headphones simply can’t replicate. The trade-off? Zero isolation. Your train seatmate hears everything. Open-backs are made for home. For the moments you truly want to listen.

The DT 900 Pro X leverages this openness better than most rivals in its price range. Its STELLAR.45 drivers represent Beyerdynamic’s latest innovation, introduced with the Pro-X series. They deliver a frequency response of 5–40,000 Hz. For context: the human ear perceives up to roughly 20,000 Hz. That extra bandwidth isn’t just for show—it lets the headphones perform more cleanly in the audible range, since the diaphragm isn’t pushed to its limits.

48 Ohms: Why It Matters

The Sennheiser HD 600 has an impedance of 300 Ohms. That means it needs a headphone amplifier to play loud enough and with control. On a smartphone, it’ll be too quiet and sound thin. The AKG K712 Pro has an impedance of 62 Ohms. Better, but still not ideal with low-power sources.

The DT 900 Pro X has an impedance of 48 Ohms. That’s low enough for any device—smartphone, laptop, audio interface, DAC. It plays loud enough everywhere without losing control of the bass. No extra amplifier needed. Just plug it in and go. For a headphone marketed as studio gear, that’s unusual flexibility.

48 Ω

Impedance (HD 600: 300 Ohms)

5-40k

Hz Frequency Response

219€

Starting Price (Geizhals DE)

How It Sounds

Neutral, but not boring. That’s the shortest description. The DT 900 Pro X doesn’t color the sound. It doesn’t add bass or boost the treble. What you hear is what was recorded. For some, that’s a letdown—they miss the bass boost of their consumer headphones. For everyone else, it’s a revelation.

The soundstage is wide. Wider than the HD 600, which is slightly more present in the mids. The K712 Pro is even wider, but sounds a bit less precise in comparison. The DT 900 Pro X sits right in the middle: wide enough for a spatial experience, precise enough to pinpoint every instrument.

Where it truly shines: complex tracks. Electronic music with layers. Orchestral pieces with large ensembles. Hip-hop productions where three synth lines play at once. The DT 900 Pro X untangles it all cleanly, without sounding clinical.

The bass is present but doesn’t overpower. A closed-back Beyerdynamic DT 770 delivers more low-end punch. The DT 900 Pro X, however, offers bass that decays more controlled and doesn’t muddy the mids. If you listen to techno and want physical pressure on your ears, an open-back headphone isn’t the right choice anyway. If you want to hear how the kick drum was produced, what harmonics the hi-hat has, and where the synth sits in the stereo panorama, the DT 900 Pro X is perfect.

The DT 900 Pro X doesn’t sound like a 220-euro headphone. It sounds like a 400-euro headphone that skipped its marketing budget.

Comparison: DT 900 Pro X vs. K712 Pro vs. HD 600

The AKG K712 Pro (from 267 euros, 62 ohms) delivers a warmer sound. More pronounced low-end fundamentals, a wider soundstage. On the downside, it’s less precise in the mids. If you mainly listen to ambient or classical music, the K712 could be the more emotional choice. Drawback: the cable isn’t removable on the original model. And 62 ohms is borderline for a smartphone.

The Sennheiser HD 600 (from 294 euros, 300 ohms) is a legend. For over 25 years, it’s been the reference headphone for HiFi enthusiasts. Its strength: a natural, slightly warm midrange reproduction that makes voices sound three-dimensional. Its weakness: with 300 ohms, you need an amplifier. It’s unusable on a mobile phone. Plus, its price has risen sharply in recent years.

The DT 900 Pro X is the most pragmatic of the three. Neither the warmest, nor the widest, nor the most emotional. But the most versatile. It works everywhere, sounds good everywhere, and doesn’t require any accessories. If you want to buy just one open-back headphone that works with everything—from your smartphone to a studio DAC—this is the answer.

For you if

You want an open-back headphone that works with all your devices
You prefer a neutral sound that doesn’t add or subtract anything
You value German-made quality built to last decades

Expect this if

You prioritize bass-heavy sound (then opt for closed-back headphones)
You mostly listen on the go (open-back headphones don’t block ambient noise)
You already own an HD 600 with an amp (the upgrade isn’t worth it sonically)

♫ Reference tracks – what the DT 900 can do

Tracks that reveal what a good open-back headphone can do with detail.

Bonobo – Kerala Layer upon layer. Open-back headphones untangle them
Yosi Horikawa – Bubbles Field recordings that linger in space. The perfect test for a headphone
Steely Dan – Aja Audiophile reference since 1977. The drum solo from the 3rd minute onward
Billie Eilish – everything i wanted Sub-bass you feel for the first time with an open-back headphone

Q&A After the Show

Click on a question to reveal the answer.

Do I need an amplifier for the DT 900 Pro X?

No. With an impedance of 48 ohms and a sensitivity of 100 dB, the DT 900 Pro X is powerful enough to use without an amplifier on any smartphone or laptop. A DAC like the iFi Zen DAC V2 can enhance sound quality, but it’s not essential. Unlike the Sennheiser HD 600 (300 ohms), which sounds rather thin and weak without an amp.

What’s the difference between this and the DT 990 Pro?

The DT 990 Pro is the older model, with an impedance of 250 ohms and a V-shaped sound signature (recessed mids, boosted bass and treble). The DT 900 Pro X, on the other hand, features the new STELLAR.45 drivers, has an impedance of just 48 ohms, a more neutral sound, and a detachable cable. If you don’t already own either, the DT 900 Pro X is the better choice.

Is the DT 900 Pro X suitable for music listening, or just studio use?

Both. Its neutral sound makes it ideal for studio work, but that same neutrality also makes it a great choice for critical music listening. You hear the music exactly as the producer mixed it. Many users on Hi-Fi forums prefer it over the HD 600 as an all-rounder.

Is the DT 900 Pro X comfortable for long listening sessions?

Very comfortable. The velour earpads are soft and breathable. It weighs around 345 grams—lighter than the K712 Pro. The clamping force is moderate. I regularly wear it for three to four hours straight without feeling any pressure points. Beyerdynamic offers replacement earpads as accessories in case the originals wear out over time.

Elias Kollboeck

Editorial Team, IBS Publishing