As a longtime fan of immersive music, one aspect of this hobby that never gets old is showing it off to friends and family who’ve never experienced the format. You get them into the sweet spot of your carefully-constructed system (yes, you do have to sit in the middle), put on a multichannel mix of one of their favorite songs, and watch their eyes widen with amazement. “Wow, I never heard that harmony vocal part before!” “It really feels like you’re inside the song!”
But then come the questions: “How do I set this up at home?” “Do I really need that many speakers?” “Do they have to be in exactly those spots?” “Where can I even buy surround music?”
Unfortunately–as those of us in this space know all too well–the answers to these questions aren’t usually what people want to hear. Yes, you really do need to put those extra speakers behind your couch. You liked that 5.1 mix of Aerosmith’s “Sweet Emotion” I just played? Unfortunately, it’s only available on a special type of disc (which won’t play in a regular CD or DVD player) that’s been out-of-print for more than two decades and costs close to $100 on eBay. The excited look on their face quickly starts to fade.
Editor’s Note: Dire Straits' Brothers in Arms (1985)–which Airsound co-founder Guy Fletcher originally performed on–is widely considered one of the best releases of that early-2000s 5.1 era. The 2005 5.1 mix was created by Chuck Ainlay, but Fletcher revisited the album for a Dolby Atmos remix in 2022. The Atmos mix is due to be released on a limited-edition Blu-Ray Audio later this year.
By the early-2010s, 5.1 music had been largely abandoned by the major labels. The format was kept alive through the decade via the efforts of a small group of content creators and a very dedicated fanbase. So the effort required to build a good system and lack of available content have always been key factors in limiting user adoption.
Much to their credit, the powers that be have taken significant steps to address both issues with the launch of Dolby Atmos music in 2020. Right off the bat, a huge catalog of music both new and old was immediately available to stream in the new format. Plus, unlike the 5.1 surround sound and quadraphonic formats that came before it, Atmos music can be experienced via a wide variety of hardware devices ranging from headphones all the way to a 12 or 15-speaker home theater system.
However, as Marvin Gaye and Tammi Terrell famously sang, “there ain’t nothing like the real thing.” Spatial audio on headphones, while an interesting experience in its own right, only offers a glimpse of the full effect on speakers–at least for me. Yet at the same time, I’m fully cognizant that most people aren’t going to hang speakers from the ceiling in their homes.
What has me most excited about the format’s staying power is the growing number of compact and comparatively-inexpensive speaker-based solutions becoming available–like Sonos’ ARC soundbar and ERA-300 speakers or Sony’s Bravia Theater Quad system. So when I interviewed Guy Fletcher last year, I was immediately intrigued by the Airsound Spatial system he’d developed with his brother Dan. He claimed not only that the system could simulate 7.1.4 using just 2-4 speakers, but that they could be placed anywhere in the room. Could such a thing really be possible?
But what really started to convince me of the system’s promise was his admission that the Mark Knopfler’s Guitar Heroes “Going Home” track (get it in the IAA shop!) was mixed in Dolby Atmos using the Airsound system. On my 7.1.4 speaker system, it sounds fully-engaging with good use of all channels. Plus, the system has since been endorsed by giants in the field such as Glyn Johns, Chris Porter, Phil Manzanera, Emre Ramazagnolu, and more.
The Fletchers were kind enough to loan me a prototype system, which I’ve had the pleasure of evaluating over these past few months. I commend them for their quick correspondence and patience with me when it came to troubleshooting. It was an incredible opportunity, and I’m excited to finally share my thoughts!
The Technology
It might seem ludicrous to suggest that you can place speakers anywhere in the room and get the mixer’s intended soundfield, but that is exactly how this system works. It’s based on a concept called dipole steering, which allows the presentation of any number of audio channels from a simplified electroacoustic architecture. Each Airsound speaker contains five drivers: one in the center, two in the sides facing outward, and two on top.
As I understand it–rather than sending out discrete loudspeaker signals (front left, front right, center, etc), the system uses a process similar to mid-side encoding to split the signal into three components: ‘main’, ‘height’, and ‘airsound.’ The ‘main’ channel holds the bulk of the detail in the audio, while the other two channels contain the information for how it’s placed in space.
The system expects to receive a discrete 12-channel input via virtual soundcard, rather than a digital bitstream–so traditional HDMI-based sources like Blu-Ray or the hi-res TrueHD/MKV downloads sold via IAA’s shop are currently incompatible. However–as many know–there is a workaround to get Apple Music on MacOS to send 7.1.4 channels of PCM directly through a virtual soundcard. So as long as you have a Mac with an Apple Music subscription, you’ve got essentially limitless material to listen to.
“The original goal for Airsound [stereo] was to create the impression of stereo from a single source. I remember when my Dad first demonstrated it to me way back in 2005: he had three loudspeakers on his mantlepiece, spread very far apart. He played me loads of music that sounded like wide stereo, but then he took the two loudspeakers that were on the sides down. It turned out those speakers on the sides weren’t actually doing anything, all the sound was being projected out from the one in the middle.”
“When Dolby Atmos came around two or three years ago now, I asked my brother Dan to investigate if it was possible to mix in the immersive format using the Airsound technology. After about six months of research, he demoed it for me in my Dad's living room with a couple of little speakers. He played me the Atmos mix of Brothers In Arms that I had just finished and it was unbelievable. I knew where some of the instruments were positioned, and they were coming from those spots even though there was no speaker there.”
Guy Fletcher, June 2024
The Setup
I was initially provided a two speaker system, which is driven by a single outboard amplifier/soundcard. The system is not wireless: each speaker connects to the amp using a custom multi-pin connector, while two unbalanced RCA output lines on the amp unit allow for a subwoofer connection. The soundcard connects to your computer with a standard mini-USB cable.
Though the speakers can technically be placed anywhere in the room, the provided instructions recommend two possible configurations for a two-speaker system. You can either put one directly in front of the main listening position and one behind (i.e. where the front center and rear center channels would be in a 6.1 system), or one on the left and one on the right (where the side surround speakers would be in a 7.1 system). I opted to go for the first option.
Moving over to the computer, the system is controlled using an app called ASAP. The settings menu is incredibly detailed, giving the user control over a wide range of features including speaker balance and configuration, audio component balance (individual volume controls for the aforementioned ‘main,’ ‘height,’ and ‘airsound’ channels), bass management, and more. It’s a bit overwhelming at first, but over time I came to appreciate having this degree of customizability and control.
First Impressions: The 2 Speaker Experience
The first song I listened to was Yes’ “Yours Is No Disgrace,” the opening track from 1970’s The Yes Album. In the original stereo version of this song, Steve Howe’s lead guitar comes from the left speaker and Tony Kaye’s organ is in the right speaker. In Steven Wilson’s 2023 Dolby Atmos mix, Howe’s opening guitar lines come mostly from the front left height speaker–to very cool effect–while Tony Kaye’s organ appears mostly over in the side right channel.
Listening to this with the Airsound speakers, I could’ve sworn my front left height speaker was firing: it was that convincing. However, the organ sounded like it was centered in the middle of the room instead of way over to the right like on the 7.1.4 array. I noticed the same problem with the synthesizer part that enters from the left rear speaker at 0:40–it felt more like it was directly behind me than way off over my left shoulder.
Next, I listened to “Lie Flat” from Bruce Soord’s Luminescence (get it in the IAA shop!). As those who’ve heard the album can attest, this is a very different kind of Atmos mix. There are individual sound objects placed all throughout the room, rather than focused into specific speaker locations.
The song starts with percussion panned directly overhead, in all four height speakers, which the system was able to simulate extremely well. When the strings first came in at around 1:30, I did get the sense they were wrapping around me from behind–but the stereo image presented by the rear speakers seemed narrower than on my 7.1.4 setup.
After that I went over to “Shagpile Bed” from Guy Fletcher’s own Anomaly (2022) record. This was unsurprisingly the most impressive of the three demos, no doubt because it was recently remixed in 2024 using a four-speaker Airsound system. The rhythm section hovered between ear-level and the heights, just like on my 7.1.4 speaker system.
So with each familiar demo track I tried, a pattern began to emerge. The position of elements that appear largely hard-panned into a single speaker (with the exception of the center channel) seemed more ambiguous, whereas ‘complex’ stereo information–like the pair of double-tracked acoustic guitars that come in midway through the first verse of “Shagpile Bed”–felt wider and more convincing.
Upgrading from 2 Speakers to 4
Based on my comments about the two speaker system’s struggle to effectively convey the left/right dimension, Dan Fletcher kindly offered to send me two more speakers and an additional slave amp for the full experience. Of course, I gladly took him up on it.
However, once the additional two speakers and slave amp arrived, I excitedly set them up only to find there was no sound coming from the side speakers. After an extended back-and-forth over email, Dan suggested that I open up the slave amp to make sure a certain component hadn’t become dislodged from the motherboard during shipping. I nervously took the lid off the unit and sure enough, that was exactly the issue! Once that piece was reconnected, everything was in working order.
Aside from the above issue, reconfiguring the system to support four speakers was relatively straightforward. Within the Audio MIDI setup menu, the two sound cards needed to be merged into an ‘aggregate’ 8-channel output. Once that was done, it was simply a matter of adding the additional two speakers within ASAP.
The 4 Speaker Experience
Now that I had all four speakers in place, I went back to my first demo track–“Yours Is No Disgrace”–to see if the issue perceiving left/right separation on the horizontal plane was still there. Since the system now had actual side channels in place, hard-panned information in those locations like Tony Kaye’s organ or the acoustic guitars during the breakdown at around the 7-minute mark was now much more apparent.
Additionally, Dan added a new feature to ASAP called ‘Multichannel Source Positions’ with different presets for speaker placement. I found that the “7.1.4 Wider L/R” setting dramatically increased the stereo spread of the front stage–especially when toeing in the side surrounds slightly, so the front channel information is being conveyed by a triangular formation instead of just one Airsound speaker.
However, I was still struggling to hear the wide stereo separation I was used to in the rear channels. For example: at the beginning of New Order’s “Blue Monday,” the main keyboard melody is locked to the right rear speaker, with its delay panned over to the left rear. Once again I was extremely impressed by the unit’s ability to reproduce height information, but that synth part in the back right corner didn’t seem as hard-panned as I’m used to.
My favorite configuration for listening actually ended up being one speaker in front, two in the sides. Taking the rear speaker out of the equation actually seemed to help to widen the back soundstage, at least in my experience. Even though both the side and rear surround channels are being handled by only two Airsound speakers, it somehow manages to distinguish the two.
Does it work with legacy multichannel formats like 5.1 and quadraphonic too?
During the testing process, I thought it would also be interesting to try some legacy 5.1 surround and quadraphonic mixes with the system. I noticed that when loading a six-channel file into ASAP, the system would send the rear channel information to the side surrounds. At my suggestion, Dan kindly added an additional preset to “Multichannel Source Positions” that put the rear speakers at 140 degrees–making it more ideal for listening to these old 5.1 releases.
First, I loaded up Steely Dan’s “Babylon Sisters” from Gaucho (1980). Elliot Scheiner’s 5.1 mix places the rhythm section and lead vocals upfront, while additional elements like the horns, rhythm guitars, and backing vocals are pushed entirely to the rear. The system did a great job resolving the stereo horn section in the rear, it really did feel as wide as on a true 5.1 setup.
Editor’s Note: Airsound is continually evolving the capabilities and fine-tuning of the system. My own insights, along with some other feedback from studio engineers, has led them to recently add a fully dynamic speaker layout–which provides ever more realism and flexibility to work in multiple Spatial Audio formats.
Finally, I also tried doing a real ‘70s quad setup with the four Airsound speakers placed in a square formation (45 degrees) around the main listening position. I listened back to a number of classic vintage quadraphonic mixes in this format, including Santana’s “Evil Ways” (from 1969’s Santana), The O’Jays’ “For The Love of Money” (from 1973’s Ship Ahoy), and Joni Mitchell’s “Free Man in Paris” (from 1974’s Court and Spark). The channel-hopping bass guitar in the O’Jays track moved seamlessly around the four speakers, just as you’d hope.
Final Thoughts
Overall, the Airsound Spatial system is an amazing achievement and a potential game-changer for immersive audio production going forward. At times, the soundfield created by the four speaker system sounded frighteningly similar to what I was used to hearing on my 7.1.4 setup. However, there were other instances where it didn’t quite deliver quite the degree of channel separation that I'd come to expect.
That being said, I would argue that the system’s shortcomings (which may vary depending on the listener’s room size, acoustics, and a variety of other factors) are made up for by the fact that it’s considerably easier to set up than a typical Atmos system. It would be interesting to do a shootout between Airsound and its consumer-grade competitors like the aforementioned Sonos ERA 300 or Sony Quad, but unfortunately I don’t have that hardware on-hand for comparison.
So, is it really possible to create the impression of having 11 channels when using only four speakers? I was admittedly skeptical at first, but–much to my surprise–the answer is actually ‘yes,’ but not without some compromise. This technology is fascinating and certainly something to keep an eye for those in the immersive space going forward.
Read more about Airsound Spatial here!
