Last week we reported that Dear Reality had announced a free ambisonics plug-in, AMBI MICRO, complementing their already comprehensive range of ambisonics and immersive audio tools. Although this free plug-in can connect to their Spatial Connect software to provide head tracking when combined with a VR headset AMBI MICRO still provides a great set of tools without this option.
The free plug-in from Dear Reality enables you to convert A-format audio from a microphone such as the Sennheiser AMBEO VR mic to B-format, as well as decode the output to binaural audio using several head-related transfer functions (HRTFs). Dear Reality have collaborated with Sennheiser to provide an accurate ambisonics conversion filter model for the AMBEO VR mic, but also provides a generic filter model for other microphones.
In this test I’ve taken a clips from 2 recordings I made for my London Ambisonics : Exteriors sound library, and run them through a combination of plug-ins. The first test uses the latest version (1.2.3) of the free Sennheiser AMBEO A-B convertor plug-in followed by the free Dear Reality AMBI MICRO to convert to binaural using the Neumann KU100 binaural head HRTF.
In the second test, I’ve used AMBI MICRO on its own to convert straight from the AMBEO A-format and go directly to binaural, using the same HRTF.
In the third and final test, I’ve used the Sennheiser plug-in to go from A to B-format, followed by Noise Maker’s AMBI HEAD HD (€189 + VAT). This can also decode to binaural using an HRTF of the Neumann KU100, and as with AMBI MICRO was made in collaboration with Sennheiser.
You can listen to the clips here on the page, or download them and listen through to see what you think. If you’d like to use AMBI MICRO or AMBI HEAD HD with some B-format ambisonic audio (the Sennheiser A-B convertor won’t be required) you can download some samples from my London Ambisonics : Exteriors sound library.
As expected, the A-B conversion using the Sennheiser AMBEO plug-in and AMBI MICRO are very similar, in fact so similar in my tests I couldn’t hear any difference. However, I did invert the output of one track to see if they would null, and was left with a very faint signal mainly at the top end, but didn’t export this for analysis. If you are running lots of processing on your signal, having one plug-in taking care of 2 jobs can be very useful, and given there’s incredibly little difference in sound I can’t see any reason not to do this.
When it comes to Ambi Head HD there’s definitely a difference in sound, as would be expected. Given the minimal difference in A-B conversion between Sennheiser AMBEO and AMBI MICRO plug-ins, I only did this test using the Sennheiser AMBEO plug-in to handle the initial conversion.
It’s worth noting that Ambi Head HD also offers head tracking when paired with an Android phone, without any additional software or hardware, and can handle inputs up to 3OA (Third Order Ambisonics). I wouldn’t say I preferred the sound of either of these binaural outputs, they were just different. I felt Ambi Head HD had more low-end, and a more impactful sound, whereas the AMBI MICRO had less emphasis at the lower mid-range of the frequency spectrum and could be defined as clearer as a result, however the sound of each might suit some recordings and not others, so having more weapons in your arsenal is no bad thing. A free time limited demo of Ambi Head HD is available, so I’d suggest downloading it and seeing what you think.