Audio predictions for the next 20 years
(2009 - 2029)So we
had some fun discussing what the progress has occurred over the
past 20 years, so how about a
bit of speculation about where we could go in the next 20.
My crystal ball is pretty good, and
definitely long-range, so I’ll take a shot at some topics I believe
will be transformational in the field of audio.
True vector-encoded surround formats
This is something that has been
desired for a long time, and certain attempts have been made in the
past (Ambisonics being a
notable one I admire). But whatever the tech, a new formalized
format for encoding a full 3D acoustic space that is totally
abstracted from the speaker configuration will arrive and be
adopted.
Vector encoding is critical to truly preserving
the spatial positioning intent of the artist/producer. Much like a
vector encoded image can reproduce well at low resolution or at 10x
the resolution (say when printing). Such as the difference between
an Illustrator image vs. a bitmap image. Scaling of the bitmap can be
done, but looks ragged and blocky as you increase magnification 10x,
but an illustrator rendering is perfect at any selected output size.
In contrast to the current discreet mess of 2,
6, 8 or more channels, vector encoded audio will finally split the
responsibilities where they belong: Spatial positioning in the
artists hands and adaptive, environment and equipment specific
rendering in the hands of the consumer.
Imaging and resolution of placement is now
controlled by the playback system and its dynamic configuration.
This paradigm is adaptable to binaural
(headphones), 2ch or multi-speaker arrays.
Get ready to see systems with dozens, even
hundreds of uniquely addressable sound reproduction emitters. Mine
will definitely be one of those ;)
Since a vector encoded sound source could be
more compact than a high-rez multichannel, expect to see delivery
via all channels, even network. Platforms such as BluRay, that
support extensible Audio container formats will likely be one of the
first to provide this in a physical media.
Sound system to room interfaces
Over the past 20 years, we have
seen huge strides in spectral management, the introduction of usable
temporal solutions (e.g Audyssey),
and these will continue to evolve.
In the future, we will see amplitude-variant
adjustments to both temporal and spectral profiles.
Like an engines RPM based fuel-map that reacts
to many input variables and adaptively selects appropriate profiles
to determine what parameters to adjust given the conditions.
Therefore, when you play your system at an
average level of 70dB, a certain profile will be in place to handle
the slight imbalance between woofer and panel (let’s say woofer is
louder), then you crank it up to get into that song you love, and at
90dB avg, the panel is imbalanced relative to the woofer, and it’s
getting shrill in the room. An amplitude-variant map would have
appropriate frequency (spectral) adjustment to bring those two back
in-line, as well as a unique temporal adjustment to minimize a
high-frequency resonance node that forms at high-volumes.
To deliver this, Power-envelopes of the system
will be tested and modeled to achieve as accurate a reproduction as
possible at any volume. Including limiters to maintain a target max
THD.
An increase in vertical
integration of speaker systems
I foresee that more and more
speaker houses will go to tighter and tighter integration of
drivers, cabinet systems, active crossovers and amplification. All
reasonable designs will have similar topologies to a
Meridian DSP speaker (Meridian has always been ahead of the
curve).
We will see most respected
solutions have:
-
Digital delivery of content and command
data (vol, room correction, steering, etc.)
-
Highly
customized DSP with driver-specific correction curves (or
dynamically adaptable algorithms)
-
A dedicated, optimal-match amplifier able
to meet all SPL and THD goals for the ‘system’
-
Implementing and integrating with
high-function room correction solutions.
The more advanced designs will be
implementing ‘steerable’ imaging, where users can select
optimizations for movies vs. music. This feature will also be
leveraged by vector encoded positional audio.
Speaker tech
Imaging arrays will be implemented
using
Hypersonic Sound Systems emitters to provide pinpoint sound
sources with minimal room effects.
The steerable array of many small
drivers designs pioneered by Yamaha in their “Digital Sound
Projector” series, will see greater adoption by vendors and wider
deployment as individual speakers that collaborate under a regime
illustrated above in ‘Vertical integration’.
Air velocity based infra-woofers (0
– 35hz) will be perfected and mass-marketed. The current
representative, the Thigpen
Rotary woofer, will evolve and become a standard
high-performance installation ‘must-have’ at a ‘reasonable’ sub $5K
price-point.
But new implementations, leveraging smart
materials and ever increasing computational and DSP power will
deliver more conventional solutions that don’t require an Infinite
Baffle sized rear-wave room. They might not get into the single
digits, but could do 10Hz pretty clean and loud.
On ESL’s I have a ton of ideas, but some are
patent worthy, so sorry, the crystal ball has a ‘non-disclosure’
cloud over it there ;)
Radical doesn’t even begin to describe some of
them.
But here’s an obvious direction for MartinLogan
and other ESL vendors, as outlined in
vertical integration, and evidenced by speakers like the Source
and the powered centers, we will see active crossovers with DSP
speaker corrections, fully dedicated and matched amplification, with
DSP implemented amplitude management (SPL limiters, etc.).
Basically, crank it as much as you want and it will always sound
good, and won’t go out in a puff of smoke either :)
[Sidebar] This is a bit of marketing conundrum for
many vendors, as for some reason, a lot of audiophiles think they
are better at picking a good amplification match for their speaker.
It’s as if Corvettes were
sold without an engine because their purchasers believed they could
better select an engine for it afterwards. I’ve seen the audio
equivalent of a Corvette with a 4cylChevette
engine , a noisy Diesel, a steam engine, a tank turbine, 2Kw
electric, oh, and maybe the occasional LT-1 ;)[/Sidebar]
Room tuning
The science of room tuning will evolve with the
introduction of highly automated spatial measurement systems (based
on analysis from pictures, it can create a 3D model of the space).
Using a combination of actual room-correction measurement data pus
the 3D model, it will run full acoustical modeling and analysis,
resulting in recommendations for equipment location, treatment
quantity, type and location.
Used iteratively, it will allow the advanced
user to tune their systems with the precision only the top people in
the field can now barely achieve.
With the rise of highly integrated speaker
array solutions along with the sophisticated room-correction system
outlined below, we will see the introduction of integrated active
room correction solutions.
Specifically aiming at the low-frequencies, we
could see panels and other smart-material based devices implement a
combination of sound re-enforcement and room mode mitigation in one
active element.
The process of measuring room acoustics will
become vastly simpler and fool-proof. A fixed-dimension multi-mic
array on a mechanized stand is placed at the ‘prime’ position. Then
a fully automated measurement process physically moves the array
while issuing the measurement tones through the actual speaker
system.
Instead of having a big dedicated acoustic
measurement computer, or needing to co-opt your PC or laptop, this
measurement system will be a basic (reasonable cost) box connected
to the network, relaying all its captured data to a cloud-based
compute array implementing sophisticated modeling software that can
crunch through hundreds of individual measurements and model the
acoustic space with incredible precision in all three axis mentioned
previously (spectral, temporal and dynamic). Using a cool graphical
UI’s presented by a web browser, the user can then see exactly what
the models look like and optionally ‘tune’ the corrections and
limits to taste.
The imaging would look like the fluid-dynamics
modeling of automotive wind-tunnel testing along with stress
analysis visualizations applied in materials sciences.
Once the correction maps are computed, they are
now accessible to the preamp or speaker processors involved in the
users system. Users will be able to store and recall many profiles
to align with various scenarios (curtains closed, room full-of
people, just me, etc.)
Smarter source to rendering management
Content will start to include much
more meta-data around the options contained in the content delivery.
Therefore, a BluRay disc could contain info on which soundtrack is
the highest resolution / best fidelity. It would contain specific
information about aspect ratio (this already there, just needs to be
propagated and used further downstream), and many more things about
the content.
Propagating this information through the
rendering chain will allow all system components along the way to orchestrate
their configurations for an optimal viewing/listening experience.
This means preamps, source playback systems and
video rendering systems all have to communicate bi-directionally
(using HDMI CEC and other protocols to-be-developed) and
self-configure.
The user interfaces of all this will move away
from being NASA control centers understood only be the indoctrinated
geek-hood, to truly end-user result oriented interactions (I want to
watch a movie, but it’s late at night).
The visibility of actual in-home data and constructive feedback
loops
In this highly connected era, and
with all the data-gathering and compute horsepower in modern A/V
systems, we will see a dramatic increase in solutions that implement
bi-directional information exchange between the A/V systems deployed
in homes and manufacturers or service companies that pop-up to help
users get the most out of their investments.
With all the aggregated data from the installed
base, manufacturers or service organizations will be able to refine
future product offerings to minimize confusion, address acoustical,
placement or configuration needs with great certainty of outcome
based on the depth and breadth of the data set.
Solutions that allow vendors to perform remote
diagnostics and config changes will continue to propagate (BTW- My
Denon AVP
preamp already has this).
So there you have a few of my thoughts one
where this is going over the next couple of decades, and if you
think any of this too radical, believe me, I held back ;-)