Nowadays, you won’t be surprised by noise cancelling and other sound enhancers. Headphones get more and more complex electronics and the most compact emitters. But full-size models are still relevant, as only they offer uncompromising audio quality. These kinds of stuff are used by musicians, sound engineers, and everyone who wants to get a natural sound without embellishments. So does this new studio headphone live up to all these assumptions or not, let’s see in this Sennheiser HD 400 Pro review below.
Manufacturers of audio equipment functions are much more diverse. For example, you can try making the headphones very small, wireless, and equipped with noise cancelling. Audiophiles, of course, will snore, but such devices are suitable for subway trips. So it turns out that even in the catalog of one brand, radically different goods coexist peacefully. Some are for fans of compactness and digital innovation, others are for fans of really perfect sound. The Sennheiser HD 400 Pro falls in the latter category.
The model came out recently but already tops Sennheiser’s line of professional open back headphones solutions. It is not only made for studio sound engineers, the Pro series will be appreciated by electronic musicians, content creators, and music lovers as well.
It is symbolic that it is the German brand that has developed universal headphones for professionals. The company has been involved in electroacoustics since 1945 and is still a family business.
Music by all means
When you first pick up the HD 400 Pro, you will immediately notice its lightness. Despite their impressive dimensions, they weigh only 240 grams without the cable. Volumetric cups completely cover ears of any size, and the sides of the inside shell don’t rest against anything.
Almost the entire exterior structure is made of durable polymeric materials. It is hard enough to withstand scratches even in daily studio work. However, where metal is indispensable, they did not save on it. Since the Sennheiser HD 400 Pro has an open acoustic design, the outer walls of the cups are made of fine steel mesh – the membranes are reliably protected, and the design acquires additional rigidity. One of the decorative grilles is squeezed into the earcup, but it sticks out nicely with the black logo. The ear cushions are soft and pleasant to the touch. There is also cut a wide cushion on the inside of the arc.
A compact 2.5 mm jack is inserted into the left case that is protected by a latch from accidental pulling or breakage. The set includes two cables: straight (1.8 m) and with a twisted central part (3 m). Both are very practical, plus the outer jacket of the short cord is made of soft plastic, which reduces rustle when it touches clothes and other objects.
We built our Sennheiser HD 400 Pro review setup with an 800 mW (50 ohms) Schiit Jotunheim balanced amplifier at a single-ended output. A branded multi-bit DAC module was installed in the device, so there was no need for an external converter.
Mobile performance was tested on a combination of a Samsung S21 Ultra smartphone and an iFi iDSD DAC (153 mW at 600 ohms), as well as on an affordable phone with a mini-jack socket. They sit on the head of the Sennheiser HD 400 PRO, as they say, like a glove. A large cushion on top and moderately flexible rollers on the cups are fully fixed, preventing fidgeting and slipping.
You don’t even expect such a comfortable yet firm grip from the plastic construction. Obviously, it was not in vain that the developers abandoned the folding design – for serious listeners, physical strength and ergonomic fit are much more important. The emitter inside the cup is rotated to ensure that the signal accurately hits the ear canal.
Headphone impedance is average by professional standards: 120 ohms. For the built-in amplifiers of smartphones and inexpensive external USB converters, this is, of course, a lot. However, the HD 400 PRO has a slightly different sensitivity – 110 dB. So the AKG K712PRO (62 Ohm, 105 dB) taken for comparison played much quieter. And don’t let the small difference in numbers confuse anyone, as quantities change rapidly.
Sounds like real
Listening began with pleasant female vocals. Ane Brun’s voice sounds free, open, and almost free of tonal impurities. It was immediately realized why the HD 400 was given the “Pro” index behind it. Ane’s acoustic guitar sounds almost real: the fine overtones of the strings and the light touch of the fingers are both clearly audible.
Switch to Trance music. The Converting Vegetarians II album by Infected Mushroom pleasantly surprises with a juicy relief sound, but, again, not at the cost of a single tonal balance. Of course, to the extent that one can talk about it on a strong electronic track. The bass deserves special mention. For a monitor model, they are extremely dense and heavy. But that doesn’t mean the lesser ones pump up like the accessory was made specifically for dubsteppers. There is no artificial overload. The bass is also fairly linear, it’s just that in open dynamic headphones they are often a little underpowered. Hence the feeling of confident articulation in the Sennheiser HD 400 Pro.
The middle range also sounds bold and dynamic, so Diana Kroll’s jazz is quite pleasant to listen to. High against the background of deep, filled with subtle shades of vocals behave with restraint. They do not try to dominate the phonogram. But as soon as you focus on them, you immediately start to catch the slightest nuance in the bowed strings and the scattering of percussion.
Higher frequencies get louder and harder on the mobile phone’s weak amplifiers. From the point of view of perfect sound, this is, of course, a necessary evil. However, Rock music sounds catchy and energetic, even on a very noisy street. In a word, Sennheiser’s HD 400 Pro headphones turned out to be not only accurate but also surprisingly versatile.
Sennheiser HD 400 Pro specifications
- Design: on-ear over-ear headphones
- Acoustic Design: Open back
- Driver type: Dynamic
- Frequenct range: 6 Hz – 38 kHz (-10 dB)
- Impedance: 120 ohm
- Mon linear distortion: < 0.05% (1 kHz / 90 dB)
- Max. sound pressure: 110 dB (1 kHz / 1 V RMS)
- Weight: 240 g (withou cable)
The Sennheiser HD 400 Pro is lightweight and relatively inexpensive professional headphones that are suitable for both daily work and leisure. The sound is tonally adjusted, but not boring. The build quality is reliable. The best studio headphones will come in handy on a rehearsal bass, in the home studio, and next to a serious music lover’s tube amplifier. Restrictions are minimal: in mobile devices with a very weak amplifier, you will feel a loud noise in the sound.