The primary purpose of this project has been delivered with the release of Severed Surround System on BandCamp. As such the project is marked as COMPLETED. The information may still be helpful, and I might come back to this idea after some other work.
This page documents current work in translating a large proportion of my music to Dolby ATMOS format and maybe Ambisonics.
This is one outcome of a sound artist residency funded and arranged by Create NSW and facilitated by ARUP.
Why use surround?
Surround and Ambisonic sound can provide an entertaining and engaging experience. It’s not appropriate for every kind of music, sometimes it’s perfect for it. Like any art form you have to build some experience before you can know. While Ambisonic is better for long term backup and storage, ATMOS 7.1.2 surround is the brand you are most likely to find in the wild mostly due to cinemas and Netflix. It’s streamed by Apple Music and Tidal but I plan to offer it as a download on a service such as BandCamp.
Every render version of ATMOS sounds different!
ATMOS is a multi-track sound format that is rendered on the end system. So an ATMOS track heard in a cinema or on Apple headphones or a Windows desktop is an interpretation of the source. What you will hear coming out of Dolby’s reference decoder is not the same as Apple’s decoder. Apple’s is a ‘tighter’ more ‘flat’ or ‘front heavy’ sound stage than the original – as if it were set up specifically for movie mixes. The result on the default Windows Sonic For Headphones is different to Dolby Atmos for Headphones. If you think that’s bad, well yeah, but the same thing happens with speakers and rooms – you just get to hear it first. Use these test links to Dolby and Apple binaural files to hear the differences.
Test files will be shared here, but they may be removed without notice as improved skills and techniques provide better outcomes.
Test link – Brassiere In Rome Severed Heads 1982 – Dolby ATMOS as an MP4 file. This requires an ATMOS renderer as described in the following page.
Test link – Brassiere In Rome Severed Heads 1982 – Dolby Binaural Render as an MP4 file. For stereo headphones NOT speakers.
Test link – Brassiere In Rome Severed Heads 1982 – Apple Binaural Render as an MP4 file. For stereo headphones NOT speakers.
OSX computer ‘Spatial Audio’
You will need a very recent Apple Mac, using one of the last two operating systems and Apple or Beats branded headphones to hear ATMOS files in Apple ‘Spatial Audio’. You are not hearing spatial audio unless you see confirmation on the audio menu drop down. Use binaural if you can’t use ATMOS.
An ATMOS MP4 file must be played via the system viewer via QuickTime Player or Apple Music (not in a third party player like VLC et al.). Browsing MP4 files online in Safari will load QuickTime Player (again – do not use a third party browser like Firefox). In general using the Apple Music app is your best bet even if you don’t sign up for online subscription. Just add downloaded MP4 files and create a play list for your albums. If you have the right hardware you’ll hear the sound.
iPhone ‘Spatial Audio’
The iPhone/iPad allow other headphone brands so long as you buy a subscription to Apple Music, however you do not need a Music subscription when using their branded headphones. The easiest way to set up phone listening is to first import and arrange all your downloaded music into Music on your desktop computer (or iTunes on Windows). Then connect the phone to your computer using a lightning cable. Synch your music library between the phone and computer. The music is now ready to be played in spatial audio on the phone.
Windows ATMOS has mostly been about game sound
Both Windows 10 and 11 include native Microsoft Spatial Sound 8.1.1.4 channel surround rendering and can play 7.1.2 ATMOS MP4s in the latest Media Player on the Windows Store. (Any Media Foundation app is ATMOS ready). There is no restriction on the brand of headphones. You have a choice of ATMOS headphone renderers – Sonic For Headphones which is built into Windows for game sound – or you can buy Dolby ATMOS For Headphones in the Windows Store. Then select to use either of these in the sound settings – like Apple’s ‘Spatial Audio’ – it’s a different image of the same thing.
To move the music over to iPhone use the most recent Windows version of iTunes.
Android ATMOS – to be investigated
Here’s info about Samsung phones. This article talks about Android.
Ambisonics
Ambisonics is a open format and comprehensive way to record and store completely spherical 360º sound. Unlike ATMOS, it has signal from all directions. Unfortunately it’s not well supported. It’s been most successful as “First Order” Ambisonics on YouTube videos and then Facebook’s mangled version of “Second Order” Ambisonics. VLC can play back up to “3rd Order” but it’s very poorly documented and only one person is trying to maintain knowledge of the process! So it sadly stays an academic exercise.
Music should be archived in Ambisonics, because formats like ATMOS are transient. 100 years from now it will be possible to decode 3rd Order audio – Dolby may be gone. It’s always possible to down-mix from 3OA to future formats. And if you don’t need head tracking, then it’s probably sufficient to provide a fixed binaural stereo soundtrack.
Up-Mixing and Down-Mixing
Up-Mixers take a stereo recording and through some complex weaving create a surround mix. If done correctly the mix should remain exactly the same when heard on the Left and Right speakers alone. Only extra speakers should cause the surround image. I’m currently practising with this technology as well as remixing tracks where I still have the multi-track. Down-Mixing is the opposite direction – from higher orders down to 7.1.2 surround and stereo.