Binaural recordings are tracks that are created with two microphones and a mannequin head and are often touted as the “ultimate realism test” for use with headphones. When played back on a high-quality pair of cans, the recordings are hyper-realistic, and can often confuse the listener's brain into thinking the sounds they are hearing are real.

There are many ways your brain can discern the direction and placement of sound – your ears are shaped in a way that allows for crystal clear and distant audio pickup in front of your head, but not so much from behind.

Typically, binaural recordings have always been tough to create, as they require specially made realistic mannequin heads, with fancy detailed microphones in the ears. However, the engineers at Sennheiser have created a product that makes these recordings accessible anywhere, by anyone with a recent iOS device.

The AMBEO Smart Headset is a brand-new product from Sennheiser produced in conjunction with audio company Apogee. It sells locally for $469.95, and due to the unique nature of this release, it has no competition at the time of writing.

To quote Sennheiser:

3D Binaural Audio recording is the process of capturing the world around you as you hear it. Sounds that occur behind you will truly sound as if they are coming from behind again. While similar to surround sound, the resulting recording is actually a stereo audio file. AMBEO SMART HEADSET can record 3D binaural audio onto any video file and anyone can experience 3D sound simply by listening back on any pair of stereo headphones.

Build

The Sennheiser AMBEO smart headset is plastic and is almost entirely white - from the tips of the IEMs, all the way down to the lightning connector. There is also a black option available.

You may be forgiven for thinking it looks like a typical IEM (In Ear Monitor) at first. But once you look closer, you will notice the two large, sleek looking grills on each side of the ear hooks. These are the microphones which are used to create binaural recordings with your smartphone. Neat!

The non-removable 1.15-meter cable has a rather chunky inline remote, which is responsible for a lot of the processing power required for creating the recordings but also houses a lot of the quick control buttons.

The AMBEO IEMs are also an unusual shape – with straight lines and corners dominating the earhooks and assembly. This is far removed from typical Sennheiser offerings, which often favour smooth contoured edges and curvy design. To me, it appears to be a design dreamed up by an engineering team rather than a marketing team, and that's perfectly OK.

The Lightning connector is the only connection these IEMs have - there's no USB type C, micro USB, or even a standard headphone jack – this product is only available for use with Apple products, and is incompatible with Android or PC devices.

Sennheiser says that there will be an Android version released in 2018.

THe Internals

Inside each earpiece is a single dynamic driver for playback – with a rated frequency response of 15-22,000 Hz.

As well as this, each earpiece contains a directional electret capsule microphone. These microphones are the unique feature of these IEMs, and serve three different purposes: 3D binaural audio recording, Sennheiser’s own “transparent hearing” function, and Active Noise Cancelling.

And if these microphones weren’t enough for you, Sennheiser have thrown in one more standard inline microphone into the cable – for standard phone calls, and Siri duties.

The DAC/remote section contains play/pause/skip buttons, as well as a rocker and a slider. The rocker and slider can be programmed for many different features (such as launching an app, adjusting the gain, or taking a call) and offer quick options to playback and recording settings.

In USe

While these IEMs can be used as typical IEMs, they truly shine when paired with the proprietary AMBEO Smart headset app.

The “Situational Awareness” feature allows for pass-through audio – directly connecting the output of the microphones to the input of the playback drivers, essentially allowing you to directly hear what the microphones are picking up (which can be quite an eerie experience).

There are two gain levels to choose from - Natural (for most situations) or Reduced mode (for anything loud, such as concerts or air shows).

The app also features a three-band, wide Q equaliser – which is applied system-wide.

While you can use standalone apps such as Apogee MetaRecorder, the binaural features will work fine with standard IOS apps as well (such as the standard camera app, or the IOS voice memo app) - but it’s worth doing your homework first, as compatibility will vary widely from app to app.

Physically, the AMBEO smart headset is admittedly bulky and slightly heavy compared to other Sennheiser IEM offerings. However, considering the capability of this headset, this is forgivable. Due to the strong lines and angles of the design, it’s also slightly more difficult to obtain a perfect snug fit easily and quickly, unlike the comparatively tiny and round edges of the Sennheiser Momentum IEM.

But still, after finding the right tips, and using the correct insertion technique, it only takes a little practice to get a reliable fit.

Recordings and sound

I tested these using the standard IOS camera app.

Due to the nature of Binaural recordings, headphones are required to get the full experience. When listening to these recordings with the Sennheiser HD800S, they were very real and realistic.

I also had some truly shocking and weird moments when playing these back, especially if I was listening to them in the same room/scenario that I recorded them in - my brain was getting confused about what it was listening to.

The recordings are unique to the audio you would find in a typical phone-camera video, as the phone microphone is usually the sole pickup point for all audio, and all sounds contained within the video are either only louder or quieter depending on their location and proximity. But with these binaural recordings, there is a whole new level of detail added, and even basic “walking around the backyard” recordings are far more immersive and hyper-realistic.

Even smaller ambient details, such as birds chirping, cars driving past, and trees rustling in the wind, are all given an exact pinpoint location during recording. I was able to play back these videos to family members and friends, and they were able to accurately point to where certain noises originated from.

For example, I recorded a video of walking around in my backyard. In this video, my daughter was running around behind me, playing with toys. The camera doesn’t once turn around to face my daughter. When playing back the video to my fiance, she was able to accurately point out the location of my daughter on the video each time. She said it was as if she was listening to the situation with her ears – not just listening to a recording.

The AMBEO smart headset can be used for music playback as well. The driver response I feel is mostly geared towards a brighter, analytical signature, with very little thump or bloom in the bass. There is plenty of detail in the upper-mids, which can be a little overbearing with general music playback, but isn’t offensive or unpleasant in any way. The main emphasis of the frequency response is in the vocal range.

This can give the IEMs a little sizzle and pop, and may not have enough bass to satisfy bass-heads – but then again, these were made to be accurate recording and playback tools, which is a job they do perfectly well.

The inbuilt DAC from Apogee does a brilliantly effective job, drawing very little power from the source device battery, and providing more than enough power to feed the dynamic drivers.

Conclusion

A neat concept from Sennheiser, with excellent execution. If you’re looking to create binaural recordings from home, you have just found the perfect tool to work with.

I look forward to seeing Sennheiser release an Android version in the future.

For more information visit Sennheiser.

Further reading: Headphones Discussion Forum

Specifications

• Colour: White, black
• Connector: Lightning
• Frequency response: 15-22,000 Hz
• Max. sound pressure level: 112dB
• Ear coupling: In-Ear
• Cable length: 1,16m

Originally published as Sennheiser Ambeo Smart Headset Review.