Sennheiser's high-tech headset puts microphones as well as earbuds in both your ears to produce incredibly immersive binaural 3D audio effects that really put a listener in the room with you. It also lets you dial the outside world up and down as you please with situational awareness and noise cancellation features. But what is binaural recording, and who's going to get the most out of these things?

What is binaural 3D audio?

Binaural recording is a special kind of stereo recording that does an extra good job of helping a listener's ears pinpoint exactly where a sound is coming from. It creates an intensely visual sense of being in the space the sound was recorded in.

Instead of just using a two-microphone stereo setup, binaural recording requires you to replicate exactly how sound comes into human ears. That means there's a left mic and a right mic, spaced several inches apart, with a big solid head mass in between them and a pair of ears to further shape the sound. Our brains have developed to use the shape of our head and ears, and the way they effect an audio signal, to locate where sounds are coming from.

The difference is remarkable. Playing a binaural recording back through headphones, you get a stunning 3D picture of the audio space that lets you distinguish location and distance of sound sources much more clearly than a regular stereo mix.

Pop some headphones on and listen to this piece of music by Yosi Horikawa to get a sense of just how beautifully a binaural recording can paint a sonic picture. It really takes things to a new level.

Who wants to make binaural recordings?

Not a lot of folk, right now. It's a bit of a fringe thing. Apart from experimental musicians like Horikawa, and fun pieces of internet audio like the virtual barbershop recording that went viral years ago, the main place I've heard binaural audio used in recent times is in ASMR videos, where it does an amazing job of creating an intimate and relaxing space.

But there's clearly an opportunity for content creators to start experimenting with this stuff. A binaural recording doesn't do anything to ruin the experience for somebody listening on a pair of speakers, but it can make a really nice difference to somebody listening in headphones – and there's more people listening on headphones than ever before.

Sennheiser seems to think this technology could make a really nice addition to a vlogger's toolkit, using the 3D audio effect to really immerse a viewer in the space a video piece was filmed in.

The AMBEO Smart Headset

The AMBEO Smart Headset is a pair of in-ear buds with ear hooks that function as a nice iPhone headset, but with a microphone in each ear to enable binaural recording, as well as a few other nifty party tricks.

So how do they rate as a set of headphones? There's not an overabundance of bass in the sound, due to the small drivers, but otherwise things are crisp and clean. The ear hook design is good in that it'll happily sit there if you happen to pop an ear out. I might not make a great headset for rigorous workouts, just because the controller section is fairly chunky. but with an extra built-in mic on the cord, it makes a great phone headset otherwise.

The AMBEO's active noise cancelling works as well as any system I've tried. It's very impressive, especially for a pair of earbuds. But since this is primarily intended as a video recording setup, Sennheiser has also added the ability to amplify ambient noise with its situational awareness feature, so you can raise or lower the volume of the outside world as much as you feel like, dialing it up at the touch of a button if somebody starts talking to you, for example. That's a really nice touch, it's handy for monitoring audio as you film. But it does make your own voice sound weird if you're speaking while you record, much like speaking with ear plugs in.

As for how well the binaural recording microphones work? Well, for something so portable and relatively affordable, I'm impressed. Sennheiser has a considerable amount of experience making pro-grade microphones, and the in-ear mics here deliver a clean, crisp and clear sound that's noticeably better than the (surprisingly good) iPhone mic itself.

If somebody talks right in front of you, or you yourself talk while you're filming, it's a fair bit quieter than you'd expect. Also, wind noise tends to leave a bassy rumble in the track if you're recording outside. But otherwise the ambient sound is terrific and the binaural effect definitely adds to the immersiveness of the experience when you watch the footage back in headphones.

They're limited in a sense – in order for the 3D audio to match up with the vision, you need to keep the phone camera pointed straight forward. Filming yourself in selfie mode would make the entire soundscape turn a very confusing 180 degrees. But within their scope, they produce a lovely effect.

At AU$469.95 in Australia (or $300 in the United States), you could look at the AMBEO as a very expensive headset, or a fairly expensive video microphone. But that's missing the point – it is something unique that opens up certain creative possibilities you can't get with other mics. It's not a massively in-your-face effect, but it's certainly something you'll notice if you're looking for it.

At the end of the day, I'm fascinated by the tech and the experience and would like to see how more creative folk than I decide to use a device like this. Virtual reality vision continues to seem like it's just out of reach, and as any video editor knows, sound is more important than vision in most cases anyway. So perhaps 3D binaural sound can be the next step forward in immersive video.

The AMBEO Smart Headset is currently available only for iPhone, but an Android version is incoming.

Check out these videos from Benjamin Lee and Mitch Cox for a taste of what the AMBEO Smart Headset can do – but put your headphones on first!

More information: Sennheiser

View gallery - 6 images