I recently had the opportunity to explore the first inaugural LA Audio
Show held the first weekend in June at the LAX Sheraton Gateway Hotel. As a
strong advocate for surround sound — especially immersive 5.1 music — I was on
the hunt for vendors demonstrating state-of-the-art 3D audio reproduction. If
you’ve had the chance to walk the ballrooms and hotel suites of a high-end
audio show, you know that 99% of the rooms feature two-channel stereo playback.
It’s a rare occasion when an audio supplier decides to go with a multi-channel
setup at a high-end audio show. Surround sound is more closely associated with
home theaters and movies, virtual reality, or gaming. But music listening can
also be enhanced when delivered in immersive, 3D audio.
It’s true that most musicians and their labels haven’t embraced
surround music mixes. Despite several attempts with quadraphonic LPs back in
the 80s and 5.1 mixes on perhaps 1500 DVDs/SACDs, stereo music seems to have a
hard lock on the industry. There are some notable exceptions if you know where
to look. Some classic rock/pop albums from the past are available in 5.1
surround including “Pet Sounds” by The Beach Boys, “A Night at
the Opera” by Queen, “Rumours” by Fleetwood Mac, and even The Beatles’
“Sgt. Peppers Lonely Hearts Club Band,” which was completely remixed in
5.1 by George Martin’s son Giles as part of the 50th anniversary set
released in May. Of course, I had to have it and actually sat for 40 minutes of
focused, uninterrupted listening like I haven’t done in many years. It’s
brilliant by the way!
How 3D Audio Works by YARRA 3DX Tube Video
Surround music offers listeners increased spatial discrimination over
mono and stereo mixes. Engineers and producers can spread individual
instruments and vocals in a much larger sound field, which opens up the presentation
and gives listeners more places to hear the elements of a song. I heard music
and vocal parts in The Beatles 5.1 surround version that I never knew existed
before — because they had a place of their own in the mix. Surround music is
simply more compelling and real than older formats. But the industry is stuck
in a classic “chicken and egg” dilemma. We won’t get more surround
music without a parallel increase in the demand for it.
But virtually all contemporary music released by the big labels and
independent suppliers is broadcast, released, and consumed in two-channel
stereo. Music fans haven’t been offered a choice because music is largely
consumed in systems that aren’t surround friendly.
Things are different in the gaming
world. The recent E3 Convention (Electronic Entertainment Expo) introduced new
gaming systems supporting immersive, 3D audio (Dolby Atmos) and content
specifically designed to deliver it was on display at the expo. Microsoft’s new
Xbox One X supports Dolby Atmos. The first game to use it is the PC version of
Blizzard Entertainment’s “Overwatch”. Other anticipated games shown
at E3 that will feature Atmos sound include “Crackdown 3” and “Gears of War 4,”
both published by Microsoft Studios.
a headphone maker, announced that it had become the exclusive channel for Xbox
One X Dolby Atmos gaming headsets.
The advancement of immersive, 3D audio — whether for movies, VR,
gaming or music — demands consumers have simple and cost effective ways to
experience it. The classic chicken and egg dilemma plays a huge role in the
development of surround sound content. If there no easy way to reproduced
immersive audio, then why should producers of that content invest the time and
effort in creating compelling programming?
The growth of home theaters systems since the emergence of the
DVD-Video format back in 1997 has been dramatic. Millions of homes have 5.1
surround sound systems and a large percentage of disc-based and streaming video
entertainment comes with a 5.1 surround mix. Gaming engines and systems have
also embraced immersive audio. Microsoft’s Xbox and Sony’s PlayStation support surround
audio and most of the biggest games take advantage of multi-channel output via analog,
USB, and HMDI connections. And of course, the rapid rise of VR/AR software adds
to the demand for easy to use, cheap playback hardware.
If you’re a fan — or just want to experience — surround sound, you’ll
want to know what it takes to pull together a system capable of delivering
immersive audio. The following paragraphs describe three different approaches
to reproducing 3D audio. They range in price from just a hundred dollars to
several hundred thousand dollars.
One: Multiple Speakers
One way to create an immersive, surround soundscape is to place
multiple speakers around a space. The ITU (International Television Union) has
standards for positioning speakers in both 5.1 and 7.1 configurations. When
listening to a movie soundtrack or piece of music through a surround sound
system, individual elements can be panned to any location along the same flat plane
as the listener’s head. Dialog, music, and sound effects can seem to emanate
from the speakers or anywhere in between. We’ve all experienced a well-mixed
soundtrack. Surround sound works!
Recently, Dolby, DTS, and Auro Technologies have added height channels
to their theater sound systems. Not content with sound on a plane, fully
immersive, 3D audio is made possible by adding additional speakers on the
ceiling. The march for more audio channels and speakers continues unabated. New
configurations such as 11.2 or 22.4 are examples of the “more speakers is
better” theory. Home theater owners can also migrate up to these new audio
formats with upward facing speakers that “bounce” sounds off your
ceiling. But, there are limitations to this method one of which requires a flat ceiling to be reasonably effective. A discrete multi-channel speaker system is the ideal way of conveying a true 3D soundscape but not everybody has the real estate or budget for this option.
The previously mentioned LA Audio Show included a very elaborate
demonstration of immersive audio. Starke Sound, an LA-based equipment and
installation company, took over 2500 square feet at the hotel and transformed
the space into two theaters. The large room featured a 52-seat theater
showcasing a 13.6.8 Dolby Atmos configuration valued at $250,000. The smaller
room was more intimate, with only 13-seats in a 9.4.4 Dolby Atmos configuration
with the system price of $145,000.
I had the chance to experience the big room with its 24-channels of
audio. There were speakers on the side and front walls, 8 subwoofers tucked in
the corners, and 6 speakers on the ceiling. They played a couple of movie clips
and a few minutes of a live music concert. It was very impressive. I guess if
you’ve got the money, space, and interest, then wiring up dozens of speakers
might make sense.
Clearly, movie soundtracks are enhanced by surround sound and live
music concerts benefit from sounds coming from all directions. The examples
played in the Starke Sound demo room were loud and made an impact on everyone
that sat through their presentation.
But I have heard intimate surround music presentations that recreate
very compelling, private, personal performances. The acoustic country duo
Hanna-Mceuen singing “Lowlands” in 5.1 surround or new folk artist John Gorka doing “I Saw A Stranger With Your Hair” make much more
impact in surround than stereo.
But is it possible to deliver a similar audio experience without the
hefty price tag, component count, and dedicated room?
I’m not a headphone guy. But I recognize that headphones have
tremendous advantages over multiple speaker setups like those mentioned above.
First, they cost a lot less (unless you go crazy and drop $55,000 on the
Sennheiser Orpheus Headphone System — claimed to be the “best headphone
sound” in the world!). Headphones can also do something that speakers
can’t. They can deliver sound to your left and right ears with zero crosstalk.
Crosstalk is when information intended for one channel or ear leaks into the
other channel or ear. The result is a reduction in the spatial integrity of the
source recording. Audiophiles love to wax poetic about the “sound
stage” of their rigs. The brass ring for them is a system that can
reproduce depth, low-level detail, and accurate sound stages. It’s obvious that
multiple speakers placed around a listener will suffer from all sorts of
crosstalk. Generally speaking, crosstalk reduces the spatial discrimination of
a multi-channel mix — either stereo or multi-channel.
But headphones have shortcomings, too. The visceral, low frequency
vibrations that come from speakers — especially subwoofers — are missing in
headphones. And stereo imagining is severely compromised when listening to
music through phones. Sounds seem to be located in the middle of your head and
the entire sound stage moves in sync with your head’s movement with any
rotational motion. It’s unnatural: the sound source should remain stationary
relative to your head’s motions, as it does in real life. This is my biggest
complaint about listening to music through headphones or in ear monitors —
getting sounds to appear outside of your head is difficult.
Solutions to these problems exist. The Smyth “Room” Realizer
(both the A8 and the upcoming A16) is a very clever device that allows owners
to experience the characteristics of any room provided they’ve been
“measured” in that space. AIX Records’ studio in Los Angeles is a
very popular room for getting your ears measured, which results in a
personalized HRTF (head related transfer function). The resultant PRIR filter
settings are used by their hardware to mimic the characteristics of a great listening
room through headphones. You don’t have to have a great acoustic listening
space. You simply need the measurements of that room, a Smyth Realiser, and a
good set of headphones. Smyth owners can get the same sound experience I have
in my studio or the best theater in the world in their apartment. Their system
really works — I’ve tried it and actually own one of their boxes.
The Smyth system also uses a small wireless transmitter and receiver
to track the rotation of your head and processes the headphone delivery to
“lock” the virtual speakers in the same location — the experience is
practically identical to playback from the speakers. In fact, many times
measurement subjects have sworn that the speakers were still on when actually
the headphones were responsible for all of the sound. The Smyth Realizer solves
the problem of “inside-your-head” audio AND the head tracking issue.
We experience the world of sound around us binaurally, which means
everything we hear comes in through our two ears. Our outer and inner ears in
conjunction with our brains, determine the intensity, frequency, timing, and
phase of any sound we hear. With binaural sound, we’re able to accurately locate
sounds in 3D space. We don’t need multiple ears placed all around our heads to
determine spatial information — just two is enough. Our sense of hearing is
amazing. It doesn’t care how big your speakers are or how large your listening
space is. All that matters is what arrives at your left and right ears. Any
“sound field” that you experience is the result of sounds coming to
your left and right ears.
So what would it sound like if a source recording made using a
binaural recording system were played back through a set of headphones?
Theoretically, the listener would hear exactly what the “dummy”
binaural head heard during the capture. You can audition binaural recordings by
visiting YouTube and doing a search. If you listen through headphones, the
effect is rather good. The sound can be perceived as coming from outside your
Binaural recording can be made using “dummy heads” with
microphones tucked behind their eardrums. There are record labels that
specialize in recording and releasing binaural recordings. However, music
recorded this way tends to sound hollow and somewhat distant. There’s no chance
to mix or balance individual instruments after the original recording session —
after all everything is captured with a single binaural head. And finally, the
musicians have to perform all of the parts — including the vocals — in a
single pass. This requirement alone means that virtually all commercially
released albums can’t be recorded using a binaural recording head. Modern
recording practices build commercial tracks one section — or even one part at
But traditional surround audio can also be processed from discrete
multi-channel mixes (5.1 or 7.1 or 11.2) into two-channel stereo binaural
signals using specialized software. This is what the Smyth Realizer does when
you plug in an HDMI cable from your Blu-ray player and watch a movie. It
calculates what signal processing needs to happen to make the Left Surround
channel appear to come from over your left shoulder when played back through
headphones. So there’s hope for immersive, surround sound delivered through
headphones. Sources have to have been recorded binaurally or the multi-channel
mixes have to have been binaurally processed in software.
Traditional music mixes and headphones are unable to deliver an
“outside-of-your-head” experience. It just doesn’t happen.
I learned about a new crowd sourcing campaign offering yet another set
of headphones the other day. This group’s headphones use drivers with graphene
speakers instead of Mylar. They claim this revolutionary new material delivers
increased frequency response (up to 63 kHz!!) and a more linear response. I’m
sure the specifications for the new phones are very good but they’re not likely
to magically reverse the “inside-your-head” phenomenon. They have a
few testimonials on the Kickstarter site (including comments from some
Grammy-winning engineers) that say exactly that — the sound seems to come from
across the room. I’m skeptical.
Three: Sound Bars
Sound bars, those small linear arrays of speakers typically tucked
under a television monitor, are the best selling audio accessory after
headphones according to the Consumer Technology Association (CTA). More home
theater owners purchase sound bars than discrete systems involving 5 or 7 or
more speakers. Why? Because they’re far cheaper, less obtrusive, and they
produce a reasonable approximation of surround sound. Prices range from a
couple of hundred dollars to more than five thousand dollars.
But how do they work and how good is the sound they project? Sound
bars have multiple small speakers arranged in a linear array. Some
manufacturers send the left and right surround channels to portions of the
array that are pointed past the listening position. They’re counting on these
channels being reflected off of the walls in your home theater and being
perceived as “non-direct” sounds. It’s not exactly the same as having
a speaker located over your shoulders but it does create an effect that is
“surround-like”. Yamaha and Denon employ this method of
“directing” sounds beyond traditional stereo setups.
Other manufacturers employ clever signal processing to
“focus” or “magnify” the presence of sound in specific
locations. These “smart” sound bars can actually deliver an
immersive, 3D audio experience — just like a binaural mix in headphones — as
long as the content is properly prepared. Remember that a complete sound field
— any sound field including 3D immersive audio — can be reproduced by steering
left channel information to your left ear and right channel information to your
right ear. As we’ve seen, headphones can do that. And it turns out beamforming
speakers can do it too.
Imagine a small array of identical speakers, each driven by a DSP chip
and digital amplifier, pointed at your listening position. By precisely
adjusting the phase and amplitude of each signal, it is possible to
“beam” discrete channels of audio to specific locations in space and newer designs can actually track your
movements and make realtime adjustments to the sound field. Listeners are not
locked into the traditional “sweet spot” any more.
The first time I experienced this remarkable capability was at the
SpatLab (Spatial Audio Lab at the University of California at San Diego). My
close friend (and the former director of the Music Technology program at UCSD)
stood at 12 o’clock, while my wife and I stood opposite each other at 3 and 9
o’clock in relation to a small sound bar called the YARRA 3DX. Believe it or
not, we all heard a different audio program. The YARRA 3DX sound bar was able
to focus three discrete audio programs to three specific areas of the room.
There was no “crosstalk” or bleed. I was amazed.
It is possible to use “beamforming” techniques to minimize
crosstalk in an acoustic space and deliver a 3D immersive audio program to a
listener without headphones! But what does it cost?
There are several commercially available speakers that use beamforming
to “expand” realism and deliver 3D audio but they’re very expensive —
costing over $50,000! In comparison, the previously mentioned YARRA 3DX speaker
and subwoofer combination is priced at $599.
The YARRA 3DX is a sound projection system that can deliver immersive,
3D audio for home theater owners, gamers, high-end music fans, and VR/AR
applications. The main speaker array has twelve 33 mm identical drivers,
controlled by an iOS or Android App, to up to three locations in a room. Users
can switch the unit between near (10-36″) and far field modes (7-15 feet)
to accommodate different applications. The main array is only 21″ long and
3″ high. The self-powered subwoofer is roughly 10 inches square and has an
internal power supply (120-240/50-60 Hz).
Comhear Inc., a San Diego-based technology company, is developing the
YARRA 3DX product and will be launching a Kickstarter campaign to bring their
product to market in early July. They demoed the unit at the LA Audio Show and
won an “Alfie” award in the “Best of: Speakers” category.
The judges didn’t quite know what to make of the little speaker in front of
them but they said, “it blew them away!” If you’re interested in
taking advantage of discounts of up to 50% off the MSRP of $599 for this
innovative product, you’ll want to visit www.yarra3dx.com and
sign up for their VIP list right away.
Surround sound, immersive audio, and 3D sound are growing in
popularity and importance as gaming, VR, movies, and music embrace multi-channel
audio. Users have choices when it comes to experiencing multi-channel audio. We’ve looked
at the three methods in the discussion above: multiple strategically-placed
amplified speakers, headphones with motion tracking and binaural content, and
beamforming sound bars. All three can deliver enhanced listening, but vary
tremendously in cost and convenience. For the money, a smart sound bar might be
just what many home theater enthusiasts need especially if their goal isn’t to reach theater reference levels that can cause one to get evicted from their condo. A smart sound bar also offers a compact solution that occupies the least amount of real estate and offers the easiest set up.
Bizarro_Stormy posts on July 31, 2017 21:43
sTonti23 posts on July 31, 2017 16:48
I too, signed up for the site after reading this article! Thank you, thank you, thank you for the up-to-date breakdown on all things Immersive Audio, Binaural Audio, 3D Audio, etc etc etc.
There’s so much to ask ya, but I’ll keep my Q’s tied to the world of VR and VR Audio.
1) You mentioned the “Starke Sound LA Audio Show” and was curious: Did they speak at all about VR Audio? Or where 3D audio is headed re: VR Headsets or VR rooms? Any more deets on that audio show and/or the full extent of what they covered? I’m LA based and will definitely look them up!
2) In the headphone section, you mentioned a crowd-funding campaign for a new pair of headphones: “They have a few testimonials on the Kickstarter site (including comments from some Grammy-winning engineers) that say exactly that the sound seems to come from across the room. I’m skeptical.”
First of all, I’m with ya. Always skeptical, BUT I have to laugh (out loud), because I may or may not have been a part of that very campaign! There aren’t that many folks out there making true Binaural headphones, so there’s a chance the pair I got are the pair you’re referring to…? I just got them this weekend and finally had a chance to toy with them (virtually my whole Saturday). They’re called Hooke Verse. Couple things off the bat: Their bluetooth (rad), they’ve got a microphone in each earbud that picks up the sound around you, and from what the manufacturer claims…they’ve got a codec that aids in recording and then transmitting (wirelessly) actual binaural audio as opposed to stitching/rendering stereo recordings.
I would love to hear what you think on this company and what they’re up to. I had a blast on Saturday and the sensation was “out-of-my-head” surround sound, or at least I thought so. But I can understand your point that it’s tough to create that feeling with headphones (especially in-ear), maybe even impossible, because of the nature of the speakers…they’re IN your head. Anyhoudini, take a look at their stuff and maybe this is the company you were alluding to??
Love your stuff!
Thanks for the article,
Douewedijkstra posts on July 11, 2017 14:19
I decided to register to your forum simply to reply to this wonderful article! It’s commendable how you’re trying to state a case for surround audio. *wipes away tears* Ever since the downfall of DVD-A/SACD I have been waiting for the next step in audio, but nothing has come by that has remotely caught people’s attention, I feel (unless you consider ‘Blu-Ray Pure Audio’ a hit, which I certainly don’t). I really do hope that as the popularity of immersive audio increases, as well as sales of home theater packages/soundbars etc., we may see a comeback of music in surround sound. I’d buy my favourite albums in surround in a heartbeat! Hopes and prayers!
gene posts on July 07, 2017 10:47
Read: Three Methods for Immersive 3D Audio