Sennheiser HD 400 Pro Reference Headphones
- Open
- Circumaural
- Impedance: 120 Ohm
- Sound pressure level: 110 dB SPL (1 kHz / 1 V RMS)
- Frequency range: 6 – 38.000 Hz
Sennheiser HD 400 Pro Review
Sennheiser has long been a leader in the headphone industry. With models that cover the entire range from consumer to professional audio to audiophile, the HD 400 PRO headphones are the latest flagship in the Sennheiser Professional series. This open-back design is made for music production, mastering, and mixing.
Sennheiser HD 400 Pro Sound
The highs are excellent—full of precision and clarity, yet never harsh. For critical studio work, there’s nothing better than a clear top end that won’t tire your ears over long sessions. That’s exactly what the HD 400 Pro delivers.
The mid-range is just as impressive. It offers fantastic range and depth, highlighting the source without pushing it too far forward. Thanks to the open-back design, the sound is warm and airy. The soundstage and imaging are also better than we expected at this price point, likely due to the angled transducers, which are becoming more common. This design helps mimic the direction of studio monitors for an even clearer and more accurate presentation.
The lows are punchy, but like other open-back headphones, they aren’t overwhelming. Honestly, we prefer it that way. Accurate audio delivery is crucial for making important decisions—a standard the HD 400 Pro meets with ease.
Overall, the Sennheiser HD 400 Pro is an outstanding choice and tough to beat at this price. If you’re looking for clear, neutral, and well-defined sound, you’ll be pleasantly surprised by what these headphones have to offer.
Sennheiser HD 400 Pro Build
The headphones feature comfortable velour earpads and an adjustable headband for a customizable fit. Even for people with larger heads, there’s still plenty of room for a snug, secure feel. However, we did notice that the headphones have a firm clamping force, which can cause some pressure around the ears.
While this helps maintain a tight seal, it also meant we needed to take more breaks than usual to rest the sides of our head. The housing seems sturdy enough for daily studio use, but most of the essential parts are made of plastic—likely chosen to keep the weight down and the price more affordable.
The HD 400 PRO looks strikingly similar to the very popular HD 560S from Sennheiser’s audiophile lineup. We didn’t compare the two side by side, but they do share a lot on paper. The 5XX series has been around for a long time, and the ‘S’ in HD 560S stands for its new 120-ohm transducer.
That move was a clear success, so it’s no surprise Sennheiser would release a PRO model with the same transducer. It uses a special polymer blend in the diaphragm to improve transient response and detail above 10 kHz. The driver’s magnet achieves better bass extension through increased power, and a damping system manages airflow.
The new transducer design brings distortion down to an impressive < 0.05% Total Harmonic Distortion (THD). The frequency response is rated from 6 Hz to 38 kHz, and the headphones come with both a coiled and straight cable, plus a 1/8” to 1/4” adapter.
The HD 400 PRO features angled transducers, which, combined with its open ear cups, create a wide and accurate soundstage. This trend of angled transducers (which is becoming more common) is said to greatly reduce distortion, especially at high sound pressure levels, and this is noticeable right away.
Transients form and fade with a clarity that really lets you focus on the tiniest details in the sound. Combined with its open-back design, the headphones deliver a vast soundscape that stretches across your field of hearing and surrounds you with impressive clarity. This becomes especially clear when judging panning choices and the placement of elements across the stereo field.
- Perfect for recording, editing, mixing, and mastering sessions
- Open-back design provides natural and accurate listening experience
- 120-ohm polymer blend transducer diaphragm and high-power drive magnet deliver the clear, deep audio that you require during sessions
- Open earcups and angled transducer design widen soundstage to professional levels
- Durable, lightweight construction with velour earpads to maximize longevity and comfort
- 1.8m straight cable and 3m coiled cable with 3.5mm connector
- 3.5–6.3mm adapter also included
Why You Need the Sennheiser HD 400 Pro
If you don’t already own a pair of open-back headphones, the Sennheiser HD400 PROs offer fantastic value and impressive audio quality. They provide a refined, natural tonal balance that inspires confidence—none of that exaggerated “smiley face” EQ curve you might find in cheaper models.
If you’re producing and mixing in a room with less-than-ideal acoustics and using budget studio monitors, we highly recommend considering the HD400 PROs as an upgrade for your setup. They can transport you to a mixing environment that feels much more expensive than what you’d get with similarly priced monitors.
Realistically, what affordable studio monitors can you name that deliver an ultra-extended frequency response [6Hz to 38kHz (-10 dB)], extremely low distortion, and “eliminate” all the room nodes in your home?
Conclusion
The Sennheiser HD 400 Pro is an interesting choice, especially considering its price point. Studio headphones can often be expensive, and while the extra investment is usually worth it, there’s a fine line between performance and value.
The HD 400 Pro strikes a great balance between the two. You get excellent sound quality and solid construction at a very reasonable price.
However, it does fall short in one area. Most headphones come with a case or pouch, which is useful for protecting your headphones. Unfortunately, the HD 400 Pro doesn’t include one.
Sennheiser likely made this decision to keep costs down and focus on the quality of the headphones themselves. In terms of performance, this approach has paid off. But if you want a case, you’ll need to buy one separately.
If you have any questions about these headphones, please let us know in the comment section below or visit the Sennheiser website for more information!
