In this article, Tom Lowe starts by looking at the basics of ambisonics sound and how you can start recording sound in this immersive format and why ambisonics is a format you should consider using.

Before we turn to how to record ambisonics and what equipment and software are out there to help, here’s a little introduction to ambisonics and its history…

What Is Ambisonics?

To start off, I turned to Wikipedia, which defines ambisonics as…

"Ambisonics is a full-sphere surround sound format: in addition to the horizontal plane, it covers sound sources above and below the listener".

So, a fully immersive sound format that enables you to have audio completely surround the listener.

Not Channel Based

Unlike other multichannel surround formats, ambisonics does not carry audio on a per-channel basis (sounds being panned to specific channels) and doesn't address a fixed number of speakers. An ambisonics microphone will capture sound from the full 360º around it, as well 360º vertically giving you height information too. Even better is that once this information has been recorded, it can be rotated on any axis in a 3D space in post-production.

The History

The science behind ambisonics was developed in the UK in the early 1970s by Michael Gerzon, Peter Felgett and Geoffrey Barton at the University of Oxford and the University of Surrey and their theoretical design was subsequently developed into a practical microphone system by Calrec Audio Limited, who launched the first Soundfield mic in 1978.

Despite the solid research and theory behind the process, it didn't gain mainstream acceptance. I can't say for sure, but I would imagine a lot of this is down to recording technology of the time. Portable recorders from companies such as Nagra did exist, but these recorded in mono, or at most stereo. Given these microphones had 4 outputs which required the phase relationship between the 4 capsules to be perfectly aligned, the practicalities of recording this format outside of a studio would be very expensive and far from portable.

In our article Overview - Sennheiser Ambeo Ambisonics Microphone And Workflow at BVE 2017 Mike Thornton referred to his early experiences of the Soundfield microphone…

“Many years ago I recorded a demo CD for AMS, then owners of the Soundfield brand. The final recording we made was a choir singing an African song whilst dancing around the mic. At that time (1991) there was only one place where you could play it back and experience the full Ambisonic experience with height and that was the demo room in the AMS factory in Burnley, not 20 minutes drive for me from Manchester.”

The first time I personally came across SoundField as a company was in the early 2000s when multichannel digital recorders were gaining popularity and becoming increasingly affordable. The microphones were still quite large and came with an external box to process the signal before recording (converting the microphone's A-format signal to B-format, more on this later), but they could be used in the field by one person. Mike used an ST250, which was a version of the original Soundfield microphone designed to be more suited to location recording.

The first microphone that really caught my attention was the SoundField SPS200. This was marketed as a software-controlled microphone, meaning that it didn't have an external processing box. The direct signal from the microphone was recorded and then processed using a plug-in to decode the signal.

There was also not much use for ambisonics recordings, besides it being a niche interest for sound recordists and enthusiasts. It could be said that this technology was a solution looking for a problem.

As Mike said in his article in 2017…

“It is only now with the introduction of immersive sound formats and with the introduction of virtual reality with binaural playback that the Ambisonics format has at last found a home and so I am looking forward to a resurgence of Ambisonics as a native format to record immersive sound in.”

He is spot on. Since the 2010s when 360º video and VR games & experiences came along, the format has proved incredibly useful in providing audio that can create an immersive experience. The solution finally had a problem to solve, giving this 50-year-old technology a new lease of life.

A-Format And B-Format

Microphones such as the SoundField SPS200, the Sennheiser AMBEO VR mic, Røde NT-SF1 and the Core Sound Tetramic are all first-order ambisonics mics. They capture four channels of audio, one for each capsule. The output from such a mic is known as A-Format. Because the spacing between capsules isn’t standardised, this raw A-Format output of the mic isn’t suitable as an interchange format because it's specific to each microphone model. That would mean anyone dealing with raw recordings from an ambisonic mic would need to know the model used and have the correct software to handle the files.

The standard format for interchange and delivery of ambisonics recordings is known as B-Format. Although there are two different versions, both are standardised and work with various software and plug-ins. One version of B-Format is known as Furse-Malham (or FuMa) and was the first version to be developed. Later, AmbiX came along, and this is now the dominant B-Format standard when working with ambisonics. It is worth noting that this is the format used by the Facebook 360 Workstation among others.

First-order B-Format, somewhat confusingly, also uses 4-channels just like A-Format, and while derived from an A-Format recording, they're not the same thing. The software that converts from A-Format to B-Format does this by taking the raw output from the capsules of the microphone and rendering it into a perfectly aligned set of signals. To achieve the best results the software must know which microphone was used to record with. This is so it can apply the correct filter during the conversion process.

The clever bit is that by manipulating the relative levels of these four channels, various formats can be output. For example, you could create a virtual stereo pair, changing the polar patterns and spacing of the microphones. You could also create a single mono source with any polar pattern, facing any direction. You could use process this to create an entire array of virtual microphones from a single source. This can all be done in post-production, after the fact.  You can also change the orientation of the mic and rotate it on any axis in a three-dimensional space and keep this as a B-Format audio file.

After recording the sound from a first-order ambisonics microphone, the A-Format signal will need to be converted to B-Format before any processing can be undertaken in your DAW. There are several pieces of software, both standalone and as a plug-in, that can do this which I'll cover later in this article.

If you want to learn more about A-Format and B-Format, then check out Julian’s excellent article Ambisonic Formats Explained - What Is The Difference Between A Format And B Format.

There are also digital location sound recorders from Zoom (F6 & F8n) and Sound Devices (MixPre-6 II & MixPre-10 II with an additional plug-in) that can handle this A-Format to B-Format processing in real-time as the signal is recorded. However, these are designed to work with the Sennheiser AMBEO VR mic only. There's nothing stopping you from using another ambisonic microphone with the above recorders, but I would advise against using the built-in ambisonics decoding. Regardless of which mic you use, the above recorders all offer gain-linking on 4 inputs. This is critical as the gain applied to each channel must be equal for the ambisonics process to achieve its full potential.

Higher-Order Ambisonics Microphones

Next, there are what are called Second Order Ambisonics microphones that have 8 capsules, like the Core Sound OctoMic on the right. There are also microphones for recording Third Order and higher such as the Zylia that you can see on the left.

The idea is that the higher the order, the more spatial information is captured and therefore the recording will have a higher spatial resolution. The result of this is that the position of each sound within that recording will be more accurate and provide a better representation of that space.

Why Record In Ambisonics

As we have said, ambisonics isn’t a new technology. It’s been around since the 70s, but it was a technology way ahead of its time. Thankfully the world has caught up, and most of the barriers which prevented it from thriving the first time around have largely fallen away. One of the most significant of these was the complexity and expense of the equipment necessary to record and decode ambisonics. Now the decoding is very straightforward, thanks to software, much of which is free, and ambisonics is experiencing a renaissance largely due to interest in VR and 360-video. Even if you aren’t involved in anything to do with either of these, ambisonics has benefits to offer anyone open to new ways of working.

1. Future Proof Capture Format - It doesn’t matter what new formats emerge in the future, as long as the original A or B-Format files are available, an ambisonics recording will be able to be rendered to any output format. Learn more about this in my article How To Record, Edit and Publish An Ambisonics Sound Effects Library.

2. From one format it is possible to output sound effects to suit both surround formats like 5.1 and 7.1 but immersive formats like Dolby Atmos because the ambisonics format has 360º coverage as well as height information.

3. Ambisonics is 360 degrees spherical, which means it captures height information, unlike conventional surround arrays.

4. Ambisonics now has become useful to a mass audience with VR headsets like Oculus Rift and Google Cardboard and head tracking headphones like Waves NX or the EDtracker make ambisonics relevant and accessible to ordinary consumers on consumer budgets.

5. It’s the only real choice for Immersive 360/VR Video. B-Format is an accepted format for the exchange of audio in these workflows. Sound effects collections come in B-Format and can be processed by various plug-ins, such as Røde SoundField or Harpex-X.

   • I wrote a piece detailing his production decisions when compiling my “London Ambisonics” sound effects library.

   • I did consider making stereo and 5.1 versions for ease-of-use, but considered that if I had bought the library, I would want the flexibility to choose how to use the sounds, rather than have decisions baked in for me. In B-format software such as Harpex-X, or the free Røde Soundfield plug-in (which has replaced the older SurroundZone plug-in now that Røde owns the Soundfield product range) the user can also decide which mode of stereo sound they’d like to decode to, such as AB, XY, spaced-omni etc. so again thought it would be best to leave this to the end-users to decide.

6. Binaural or stereo can sound good but are static. When wearing headphones the sound field moves with your head. If you capture 360 spherical you can choose your viewpoint post-capture. Ambisonics can be processed to give a Dynamic Binaural output where the audio tracks the viewpoint of the listener for a genuinely immersive experience.

7. If you are someone who records music in stereo and thinks this ambisonics thing isn’t relevant to you, you might be missing out. Anyone who has seen virtual mic systems like the Townsend Sphere will have seen that, as well as the mic modelling (which is the principal feature), the mic also offers control over the polar pattern post-recording. The ability to do this, in stereo through 360 degrees opens up some interesting possibilities. For example, what if you were to capture a group of three backing singers arranged around an ambisonic mic in a single pass. Post record, you could use a mono hypercardioid pattern aimed at each singer in turn and the three bounces would have an excellent rejection of the other two singers and any spill would be perfectly phase-coherent because they were all captured by the same mic. You could try something similar on a drum kit or a string quartet, there are so many possibilities.

Equipment Suggestions To Get You Started Recording In Ambisonics

I've put together a list of some available equipment to start recording in ambisonics. This list is not exhaustive and is not an endorsement of any brand or product, it’s simply a list of equipment you may find useful to get started. Prices are correct at the time of writing.

Microphones

Sennheiser AMBEO VR microphone - $1,295

In this video shot at BVE 2017, Sennheiser's Customer Development & Application Engineer Andy Lillywhite takes Mike Thornton through a demo of their Ambeo microphone as well as a demonstration of potential ambisonics workflows used to produce binaural audio for virtual reality content.

When the Sennheiser AMBEO VR mic was announced in late-2016, I was immediately interested. This was an affordable first-order ambisonic microphone made by a leading brand. Around the same time, 360 video and VR was starting to gain traction, and various plug-ins for working with 360/ambisonics sound were starting to come to market. With this in mind, I purchased the AMBEO and a suitable recorder, which in my case was the Zoom F8. This has become a very common combination for people working with ambisonics, and with good reason. The one thing missing from my kit was a good windshield.

To learn more and listen to examples of the different windshield options check out my article Test - Using The Rycote Stereo Cyclone With Sennheiser Ambeo Microphone For Ambisonics Location Recording.

Røde NT-SF1 - $999

At NAB 2018, Rode announced what they are claimed was the first broadcast-grade, 360-degree surround first-order ambisonics microphone, the SoundField By RØDE NT-SF1 Ambisonic Microphone. Freedman Group CEO Damien Wilson explains...

“When The Freedman Group acquired SoundField in late-2016, the aim was to continue producing the premier 360-degree audio capture loved by the professionals who bring us cinema sound and 7.1 broadcast.”

Rode announced that it is based on a completely new capsule design, enabling the NT-SF1 to offer extremely low noise and “unprecedented smoothness and extension of frequency response”. The ambisonic arrangement and tuning are apparently drawn directly from high-end SoundField technology, "ensuring the most accurate spatialisation possible for the ultimate in 3D audio positioning".

You can learn more about the Røde NT-SF1 in our article RØDE Announce The SoundField By RØDE NT-SF1 Ambisonic Microphone.

Core Sound TetraMic - $625

Core Sound explains that the TetraMic is more than four microphone capsules on a tetrahedral mount. Building a TetraMic starts with a large batch of carefully assembled microphone capsules, pre-selected for sensitivity and frequency response. Each capsule is then tested for sensitivity, frequency response, directivity pattern and other parameters.

Next, they select four well-matched capsules and confirm their compatibility. Then another round of testing begins, this time for the complete tetrahedral assembly. All in all, each TetraMic undergoes more than seven hours of assembly, testing and calibration. Each TetraMic exits the test phase with its own calibration and correction files, for the VVEncode plug-in.

In addition to modelling any number and type of coincidently positioned first-order microphones, you can model spaced microphone arrays (e.g., ORTF) by using more than one TetraMic.

Core Sound OctoMic

The Core Sound OctoMic has been designed to be an ideal microphone for recording Virtual Reality (VR) projects, including cinema, video games, music and ambience. In post-production, OctoMic allows users to define arbitrarily complex microphone configurations and dynamically track sound sources in space. During playback, it allows for dynamic head-tracking and an unlimited number of playback speaker configurations.

OctoMic aims to offer significant improvements over 1st-order ambisonic microphones. The improvements are attractive for cinema, gaming, music and ambience, for three reasons…

1. It is far better at preserving the perceptual cues necessary for a listener to precisely locate sound sources.

2. It provides a much larger "sweet spot" for listeners. While first-order ambisonic microphones have a "sweet spot" around the size of a human head, OctoMic's "sweet spot" can accommodate multiple listeners without degrading a recording's sound location perceptual cues.

3. OctoMic can be used 50% farther away from the sound source while maintaining the same directivity index.

Pair it with a suitable eight-track digital audio recorder, such as the Sound Devices MixPre-10T or the Zoom F8 and it's ready to record.

Zylia ZM1 Microphone Array - $699

The main hardware of the Zylia system is a high-quality microphone with 19 capsules that connects to your Mac via USB 2.0, giving a third-order ambisonics recording system. The microphone casing is made from solid aluminium and has an LED status ring running around it, making it look a bit like a droid from a Sci-Fi movie.  

Zylia records at 48 kHz sample rate at 24 bit.  It's easy to set up, just place it in the middle of your musicians between 1.5 and 2m away. Any gain adjustment that may be needed takes place inside the Zylia Studio software and is between -12dB to +32dB (0.5dB steps).

There is no limit to the number of tracks or audio sources that can be recorded and in post record processing the individual instruments can be separated out for later mixing or editing. Background noise and bleed is automatically removed.

The 19-capsule ZYLIA ZM-1 microphone array has been equipped with XENSIV™ digital MEMS microphones from German-based Infineon Technologies. With a 69dB signal-to-noise ratio, the capsules deliver a 105dB dynamic range and high output linearity up to 130dB Sound Pressure Level.

If you want to learn more about recording with the Zylia ZM1 Microphone Array, check out our 2-part review by James Ivey.

In this first part of the review, James talks about the basic idea behind the Zylia system and about how it is not designed to replace a full multi-microphone large scale recording solution. Zylia is more about record your band or groups practice sessions than producing a CD ready recording but there are demo recordings and then there is what Zylia is able to offer in terms of capturing the moment when inspiration hit.  James continues, showing how to set up and calibrate the microphone and software to get the best possible results. 

In this 2nd part of this review, back in the studio 2 days after the recording session, James shows what you can do with the recordings inside the Zylia Studio software. He goes on to show how the Zylia Studio software can export not only a stereo file but also the instrument stems with minimal bleed from the other instruments. These stems James exports into Pro Tools to show how they can be further manipulated.

Recorders

Zoom H3-VR - $249

The Zoom H3-VR virtual reality audio recorder is a solution for capturing and processing spatial audio for VR, AR and mixed-reality content. With a built-in Ambisonic mic, recorder and decoder, the H3-VR puts 360-audio in the palm of your hand.

Normally capturing VR audio requires a dedicated Ambisonic mic, a separate recorder and a computer for encoding the audio from raw Ambisonics A format to VR-ready Ambisonics B format. With the H3-VR, all of the encoding and decoding is done on board, saving you both time and money.

For this video, Zoom asked Benedict Green, co-founder of EccoVR, a company specializing in the creation of high-end spatialized audio, to discuss his experience recording with the H3-VR while on a 360º video shoot at Malibu Creek State Park, CA.

Zoom F6 - $649.99

The Zoom F6 is a professional field recorder, featuring both 32-bit float recording and dual AD converters, designed to provide an unprecedented amount of dynamic range. With 6 inputs, Zoom’s solid time code, multiple power options and wireless control, the F6 could be your new secret weapon.

The F6 is equipped with six professional-grade preamps. Featuring a low noise floor (-127 dBu EIN), high gain (up to 75 dB), and selectable mic/line levels for each input, the F6 is built for location sound.

The F6’s Ambisonics mode offers precision A-to-B decoding and balanced gain linking, enabling you to capture spatial audio for VR, AR and more. You can download the FREE Zoom Ambisonics Player software to decode and edit your 360-audio.

Zoom F8n - $999.99

When developing the F8n, Zoom Technologies had it their mission to offer every sound professional the tools to create something exceptional. With features such as Advanced Look-Ahead Hybrid Limiters, Zoom AutoMix, and mic/line options for both XLR and TRS inputs, the F8n is a very cost-effective solution.

The F8n is equipped with Advanced Look-Ahead Hybrid Limiters that provide overload protection no matter what comes your way. By adding a 1 millisecond delay, the limiters “look ahead” anticipating clipping before it’s recorded. Limiting is applied to each of the 8 channels simultaneously at full resolution, with 10 to 20 dB of headroom to ensure pristine audio on every take.

The F8n features a low noise floor (−127 dBu EIN) and high gain (up to 75 dB). Mic/line levels are selectable for both XLR and TRS inputs.

Zoom AutoMix is designed to be your new assistant sound editor. This software automatically adjusts the levels of your mix to reduce the amount of ambient sound, so you can focus on what really matters.

Capable of recording 360-audio, the F8n’s Ambisonics mode features A to B decoding, gain and settings linking, and a customised metering screen.

As well as me, Mike Thornton also owns a Zoom F8 (the precursor to the F8n) and for a variety of work including location recording work for radio drama and documentaries as well as corporate conference recordings where the Zoom F-Control comes into its own.

To learn more and to see what Mike thinks of the Zoom F8 and F-Control hardware check out his review in our article Review - Zoom F8 Field Recorder And F-Control Remote Controller.

Sound Devices MixPre-6 II - $970

If you record field audio, sound effects, podcasts, voice-overs, music, audio for film, or are just starting your audio journey, the MixPre-6 II could be the one for you. With four low-noise Kashmir preamps, you can record multiple actors, multiple podcasters, or audio for film with superior quality all the way up to a 32-bit float bit depth and a 192 kHz sample rate onto 8 tracks. The MixPre Series has been redesigned for increased performance to offer 142 dB of dynamic range.

You can download the Ambisonics Plugin to record in 360° audio and monitor binaurally with an ambisonic microphone like the Sennheiser AMBEO and your MixPre-6 II.

Sound Devices MixPre-10 II - $1616

The Sound Devices MixPre-10 II is very similar to its smaller cousin, the MixPre-6 II. The main difference is that the MixPre-10 II has eight ultra-low-noise Kashmir microphone preamps with adjustable limiters, rather than the 4 that the MixPre-6 II and can record onto 12 tracks instead of 8.

As with the MixPre-6 II, you can download the Ambisonics Plugin to record in 360° audio and monitor binaurally with an ambisonic microphone like the Sennheiser AMBEO and your MixPre-10 II.

Software

So, you've made your first ambisonics recording, now you can process it to be listened to on headphones in binaural, on speakers a stereo or surround sound, an immersive format such as Dolby Atmos or as an ambisonics track to go with a 360º or VR game. Here are some of the plug-ins which can do this.

Sennheiser AMBEO A To B Format Converter - FREE

The AMBEO A-B Converter is the free tool that converts the output of the Sennheiser AMBEO VR Mic into Ambisonics B-Format. After the conversion, it is directly compatible with the spatial audio format of both YouTube and Facebook 360 videos. The plugin supports both FuMa and AmbiX output and has a specially tuned “Ambisonics Correction Filter” that improves spatial accuracy when used with the AMBEO VR Mic. It’s also possible to define the recording position and adjust the orientation to realign with the camera angle. The plugin is available as VST, VST3, AU and AAX for both Mac and Windows.

SoundField by RØDE Plugin

The new free SoundField by RØDE plugin replaces the original free SurroundZone2 Plug-in For Soundfield Recordings and offers a new approach to ambisonic processing, coupled with an intuitive new user interface. It has been designed to offer the most accurate ambisonic rendering available.

RØDE say that the SoundField by RØDE plugin operates in a completely different way to traditional ambisonic processors. Eschewing the matrices and correction filters of previous generations, it utilises state-of-the-art frequency-domain processing to deliver improved spatial accuracy at all frequencies.

The SoundField by RØDE plugin allows the user to quickly set up mixes for all the common surround-sound formats, from 5.1 through to 7.1.4 (with-height) formats. Custom formats and speaker arrays can be quickly catered for, giving unparalleled flexibility and control.

The plugin can take in ambisonics audio in A-Format, B-Format (FuMa), or B-Format (Ambix) and output the audio in B-Format (FuMa), B-Format (Ambix), Mono, Stereo, 5.1, 7.1, 5.1.2, as well as Dolby Atmos formats like 7.1.2, 5.1.4, and 7.1.4.

Note that it can only take the A-Format from the RØDE NT-SF1 mic but can take the B-Format signal from any other first-order Ambisonics mic. So as long as you use the appropriate A to B-Format converter plugin or application to get into B-Format, you can use this plugin to convert the ambisonic audio to a channel based format of your choice.

dearVR AMBI MICRO - FREE

Dear Reality, the makers of dearVR ambisonics and immersive audio software, have released AMBI MICRO, a free plug-in that converts ambisonics A-format to B-format and binaural audio with the added twist of supporting head tracking with a VR headset.

dearVR have produced this free plug-in in cooperation with Sennheiser meaning it has an A to B-format converter optimised for their AMBEO VR microphone.

When encoding to binaural, you can use one of 4 head-related transfer functions (HRTFs): DearVR, Facebook360, YouTube360, and the Neumann KU100. This means if you have a relatively simple job where you’re editing ambisonics recordings to go alongside a video, and you’re not adding additional sounds, you could use this whilst editing to get full head tracking as well as hearing what it will sound like on your intended delivery platform. It also integrates with other products from the dearVR line for a full ambisonics workflow from end-to-end.

Harpex-X

Harpex is a signal processing algorithm designed to extract the maximum amount of spatial information from sound field recordings. With the Harpex plug-ins, content creators use this technology to transform sound field recordings in A-Format and B-Format (FuMa & AmbiX) into the standard surround and 3D surround formats used in film and television, coincident, non-coincident and binaural stereo, or higher-order AmbiX for VR and AR applications.

Unlike traditional ambisonic decoders, Harpex is an active matrix processor for sound field recordings. This allows Harpex to do some unique things. Harpex can produce surround decodings with far greater channel separation than what is possible with passive matrixing, which in turn leads to a much larger sweet spot, allowing sound field recordings to be used in large venues like movie theatres, even supporting modern 3D surround formats like Dolby Atmos, IMAX and Auro 3D. Another advantage of the higher channel separation is the virtual elimination of phasing - an unpleasant sound colouration that changes as listeners move inside the listening space.

With its binaural decoding mode, Harpex is able to produce headphone-adapted stereo similar to artificial head recordings. In virtual reality applications, where the sound field needs to be rotated to match the user's head orientation, the standard audio format is AmbiX. Harpex is able to produce up to 3rd order AmbiX output from sound field recordings.

In our article, Test - Sennheiser AMBEO A To B Format Convertor, Soundfield SurroundZone 2, Harpex-X and Noise Makers Ambi Head Plug-ins, I compared Sennheiser AMBEO A To B Format Convertor, the Harpex-X ambisonics plug-in, which now features its own input setting for the AMBEO microphone based on measurements and some reverse engineering by Harpex and v1.3 of Noise Maker’s Ambi Head product, which now features new HRTFs (Head Related Transfer Functions) to take B-format and create a binaural output.

I recorded some new material in central London, especially for the test. With various sirens, people talking, building work, and buildings for the sounds to reflect off, I felt this would be a good test of spatial definition and positioning of sound.

Other than the decoding plug-ins, no other processing was used on the audio, and I have also provided the un-processed A-format audio from the AMBEO mic so you can do your own tests.

Check out the article to listen to all the test files and what I thought of them.

How To Record, Edit and Publish An Ambisonics Sound Effects Library

To conclude this look into how to record in ambisonics, in my article, How To Record, Edit and Publish An Ambisonics Sound Effects Library, I explain how I went about producing and releasing my first Ambisonics sound effects library. Having purchased the Sennheiser AMBEO VR mic and a Zoom F8 recorder back in January 2017, I began making recordings around London to start building a library of sounds for my own use for 360 video and VR projects, which were in the pipeline.

At the same time, I was also keeping an eye on what was available in the way of ambisonics commercial sound effects libraries. There were a few libraries available, but none that were of London, or even had a few sounds of London within a library.

To test out my ideas, I spent a few days going around London locations that I thought would be useful to anyone who needed sounds of London and tentatively started building a collection of recordings.

Read the article to see how I got on and download 3 sample files, each one 3 minutes in duration in first-order ambisonics at 96kHz sample rate. The 3 free recordings are Borough Market, Trafalgar Square and St James Park. Enjoy…

In Conclusion

There you have it, Ambisonics developed back in 1970s, was way ahead of its time and with the development of a range of immersive formats including virtual reality is now a solution to a problem.

Unlike other multichannel surround formats, ambisonics does not work on a per-channel basis and so doesn't address a fixed number of speakers. An ambisonic microphone will capture sound from the full 360º around it, as well 360º vertically giving you height information too. Even better is that once this information has been recorded, it can be rotated on any axis in a 3D space in post-production and be outputted into the channel-based immersive format of your choice.

Still not convinced? If you are someone who records music in stereo and thinks this ambisonics thing isn’t relevant to you, you might be missing out. The ability to do this, in stereo through 360 degrees opens up some interesting possibilities. For example, what if you were to capture a group of three backing singers arranged around an ambisonic mic in a single pass. Post record, you could use a mono hypercardioid pattern aimed at each singer in turn and the three bounces would have an excellent rejection of the other two singers and any spill would be perfectly phase-coherent because they were all captured by the same mic. You could try something similar on a drum kit or a string quartet, there are so many possibilities.

Lastly, with the development of low-cost microphones and recorders, the cost of entry into ambisonics is much more affordable than it used to be in the early days. Have a go, you may be surprised.