NEW SOUNDBAR
DIMENSION
THE HISTORICAL KEY STAGES OF
THE DEVELOPMENT OF A NEW
AUDIO DEVICE
The history of the audio industry
is marked by the appearance of
new audio devices in response
to the needs and expectations
of the times, as well as to the
new formats used in music
and cinema. Talking pictures
from the late 1920s, with their
colossal budgets, were the
cause for the major modern
technologies used in sound
reproduction. Then came
the radio, bringing amplified
sound to homes around
the world, followed by the
stereo system when stereo
microgroove records became
widely available in 1958.
Then, the Dolby Surround AC3
LaserDisc in the early 1990s
gave rise to the first 5.1 Home
Cinema systems. The iPod in
2001, followed by the iPhone
in 2007, brought downloaded
music into the household with
its docking stations, streamers
as well as other wireless and
multi-room devices...
The transition from cathode
screens to flat screens, first
with plasma displays, then
with LCD and finally OLED
displays, brought about a
paradigm: the sound projector,
the predecessor to today’s
soundbar.
In the 1980s, a lot of research
went into reproducing sound
waves from basic microsources.
The balance between sight and
sound is essential. Beyond its
dimensions, the image - with
the arrival of 4K resolution
and the contrast and definition
which characterise it – requires,
more than ever, a level of sound
quality which is no longer
limited to surround sound
effects but which also requires
dynamics and definition.
A parallel can be drawn
between the research carried
out on image digitalisation. This
"pixelation" of sound opened
the way for spatialisation from
only one source. This research
was based on mathematical
algorithms which used microtransducers controlled by DSPs
to recreate a holographic sound
image by using the reflections
of very focussed beams of
sound fired at the walls of the
listening room. In 2002, Pioneer
introduced the PDSP-1 to
accompany flat screens with a
50kg (100lbs) futuristic-looking
device based on the generation
of narrow beams of sound from
254 micro-speaker drivers.
This concept product valued
at €35,000 was never really
launched on the market,
apparently due to patent
issues…
The soundbar is not a new
concept. It dates back to
the early 2000s when sound
projectors were produced to
accompany the first plasma
flat screens. They brought an
essential design dimension to
the TV world and hence created
a demand for acoustic solutions,
which would provide the same
experience of surround sound
in cinemas, while blending in
with the design of the screen.
A solution that was discreet and
cable-free!
The Pioneer PDSP-1 was at the origin of the sound
projector "concept". 50kg (110lbs), €35,000€.
The Yamaha YSP-1 is considered as being the first veritable
multichannel soundbar.
In 2004, Yamaha announced the
launch of its sound projector, the
YSP-1, which was based on the
same concept, but in the form
of a horizontal bar, weighing
less than 15kg (30lbs) with 40
micro-transducers powered by
2W amplifiers and two 4’’ (11cm)
woofers powered by two 20W
amplifiers. This compact sound
projector offered an elegant
and easy-to-use alternative to
the invasive 5.1 systems which
were considered off-putting in
terms of use, without forgetting
the key point of getting rid of
cables. Costing €1,500, such a
product, so full of technology,
was outstandingly competitive.
efficiency integrated amplifiers
and powerful DSPs - which
were becoming affordable - the
integration of five channels into
a compact all-in-one product
was finally conceivable.
At the same time, distribution
promoted 2.1 soundbars,
which were a poor substitute
adapted to the shape of new flat
screens, and unable to manage
the multichannel sound of the
increasingly sophisticated DVD
soundtracks.
Moreover, the fact that the core
expertise was from electronic
music instruments gave a
competitive advantage to
Yamaha. Its expertise of digital
processing and the elaboration
of the product placed the bar so
high for its competitors that the
Japanese brand’s supremacy in
this emerging market segment
went undisturbed for nearly five
years.
The Panorama was the first model
to use acoustic solutions derived
from the world of high-fidelity, i.e.
two 31/2’’ (90mm) woofers powered
by a 50W amplifier, two 3” (75mm)
midrange drivers and a tweeter,
and four 3’’ (75mm) midrange
drivers for the surround channels.
The latter were powered by five
25W amplifier channels. The
surround channels are angled
so the beams of sound are fired
laterally, causing the reflections
off nearby walls of the listening
room to recreate enveloping
virtual surround effects.
In 2009, Bowers & Wilkins
launched Panorama, the first
modern compact soundbar.
It was trendy, easy to install,
truly multi-channel, and it
was manufactured by a leader
in the world of acoustics.
Thanks to advances made
in microelectronics, high-
This required a thickness
of nearly 7 1/2’’ (19cm). The
Panorama indisputably set
the new standard in terms of
quality by combining a wide
soundstage with the energy and
sound texture close to those
of high-fidelity. Once again,
conventional speaker drivers
were making a comeback.
Sound projectors equipped
with micro-transducers
provided a solution in terms
of spatialisation, but they
were very limited in terms of
energy to reproduce two crucial
octaves (125Hz-250Hz, and
250Hz-500Hz), which include
the first harmonics necessary
for producing a realistic sound
signature. Even adding a
subwoofer doesn’t resolve
this, and actually makes things
worse, as a masking effect
accentuates the deficiency in
this register.
A more modern version equipped with HDMI connections and
a new tactile user interface was
launched in 2012 to maintain
its position as a benchmark
product. The price of the new
Panorama 2 was set at €2,000.
The B&W Panorama is considered the benchmark of modern
soundbars.
THE ORIGINS OF DIMENSION
By the end of 2011, Bose
made its entrance into the
soundbar market with its
€1,499 Cinemate 1SR. More
accessible and coinciding with
the explosion of flat screen
sales, it was a huge success
and met the expectations of
consumers looking for compact
solutions, which were easy
to install and use. In only
six months, the soundbar
had finally achieved true
recognition and respectability
as a new widely accessible
high-end product!
time of touch screen technology and smartphones. That’s
without taking into account the
fact the commercial production
of such miniaturised products
requires volumes of sales on a
completely different magnitude
to what we were accustomed
to. In short, it was a high-risk
and very ambitious project!
Finally, the launch of the Sonos
Playbar in 2013 marked the last
significant stage. Although it
was limited to a 3.0 system,
this affordable and connected
product made soundbars desirable and trendy objects...
1. The thickness had to be less
than to 31/2’’ (9cm) to be compatible with flat screens, knowing
that 50% of flat screens are
wall mounted.
The origins of Dimension and
the choice of distinction
By the end of 2011, we at
Focal had a clear vision.
A new market segment for an
acoustic product was emerging and attracting consumers.
How were we to deal with this
in regards to the brand image
and how would we distinguish
the brand faced with competitors who were bigger and more
powerful than us in the AV sector? What’s more, the prerequisites to enter this market in
technological terms were set
so high that the task seemed
extremely arduous. Indeed,
apart from the acoustics, many
technologies were foreign to
us. Modern HDMI v1.4 connectivity, digital amplifiers, switching power supplies, DSPs
with their associated programming, and even user interfaces
have to be up to date in this
Five key points for success
were identified to determine
whether we were able to compete in this new market segment at this level:
2. Modern HDMI v1.4 connectivity
was required, which was compatible with ARC and CEC features
to allow interconnection between
flat screens, DVDs and set-top
boxes and ensure usability for
the general public (even though
manufacturers such as Bose and
Sonos limited their devices to
optical audio cables which didn’t
offer such functions).
3. Amplifier power, which
still has a strong marketing
impact, needed to be high. The
miniaturisation of acoustics
requires an exponential
increase of the power needed
to achieve the desired result
in terms of dynamics.
4. We had to meet market standards, it had to be compatible
with Dolby Digital and DTS,
which are prerequisites in the
eyes of the general public.
5. Finally, the soundbar had to
be self-reliant in the sense that
the bass frequency response
had to be low enough so a
subwoofer wouldn’t be required.
The subwoofer should be
optional for enthusiasts looking
for thrills or for use in large
rooms.
Our first clue came to us in
2012 when we discovered the
European patent WO2005/015950
dating from 2005 of an ultra-flat
speaker driver originally designed for the car-audio market.
This 4” (10cm) wideband speaker
driver had amazing characteristics: it could span a spectrum of
60Hz to 20,000Hz with very low
directivity.
This component with an excursion of close to 3/16” (4mm), 10%
of its thickness, was the answer
in terms of miniaturisation. It
was also the solution to the
first point regarding system
thickness and to the fifth point
of not requiring a subwoofer.
There we have our distinction based on our expertise in
acoustics. This consequently
proved to be a very wise choice
- even wiser than we had imagined...
That left us with the three other
key points. It was Steve Job’s
approach, which enlightened
us. He said that in the world
of modern technology, it is
important to seize innovation
not when it emerges, but rather
when it has matured!
of powerful state-of-the-art
DSPs as well as an intuitive
user interface with an elegant
design.
Wanting to develop additional
technologies in-house, which
don’t belong to our core activity,
no longer makes sense: the
NIH syndrome (Not Invented
Here) is over in this increasingly complex world. Finding
existing products made in Asia
is illusory and doesn’t correspond to our brand’s approach
based on a true identity.
By August 2012, we had
the basic building blocks to
consider a Focal SoundBar
project. However, we had a
long way to go to see/hear if
we were capable of making
a breakthrough considering
our already established
competitors. We needed to
know if such a project was
feasible... Innovation means
exploring the unknown, and the
best and only way to do this is
to make prototypes. So, that is
what we decided to do.
Luck was on our side thanks to
our partnership with Naim who
enabled us to find a European
partner capable of providing
us with solutions in terms of
a modern electronic platform.
We required a platform, which
supported the necessary video
connectivity, next generation
amplifiers and power supply
units, software management
By assembling the building
blocks, our first prototype
was completed by mid-2013.
The first results in direct
comparison to our competitors
left us perplexed. Combining
surround spatialisation
and dynamics to achieve
an expressive and coherent
sound for musical listening
seemed out of reach. So, we
went back to the basics and
explored a different path to our
competitors.
The basic ideal fundamental
principle of a 5.1 system was
that besides the .1 channel
of the subwoofer, it should
have five strictly identical
emitters. We already had
those with our low-directivity
wideband speaker drivers.
But how could be manage
surround spatialisation
with low directivity, whereas
our competitors used the
reflections of narrow beams
of sound to create virtual
surround effects?
Sensitivity - dB SPL/watt
100.0
95.0
90.0
85.0
80.0
Patented 4” (10cm) speaker driver. directive avec un excellent rendement.
Despite its thickness of only 17/16” (36mm), it had an excursion of nearly 3/16”
(4mm), a wideband response and low directivity with excellent efficiency. On the
left, it is response on a flat baffle panel.
75.0
70.0
65.0
60.0
55.0
50.0
overplot
30.0
100.0
1000.0
Log Frequency - Hz
10000.0
WIDEBAND SPATIALISATION
Five identical channels for an absolute coherence in 5.1.
Our work on DSPs opened
the way. Instead of striving
to create very high-directivity
(very narrow) beams, wasn’t
it better use the power of
modern DSPs to also work on
the phase and on the different
delays of the beams from our
four channels (front left and
right channels, and left and
right surround channels)?
If we transpose this into optical
terms, where the competition
used walls as acoustic mirrors
to create the virtual illusions
of surround sound, could we
not control spatialisation at
the source to broaden the
soundstage, like with an optical
lens?
Fortunately, we already
had speaker drivers whose
emitting centre in the form of
an inverted dome was situated
on the same front plane of the
speaker driver. Consequently,
they were low-directivity
(wide dispersion) , whereas
conventional solutions with
cone-shaped speaker drivers
were naturally directive. This
led us to explore another path:
full band phase control, thus
guaranteeing total coherence
of the audio message.
It had been general practice
to create auditory illusion
artefacts only in the high
frequencies, due to directivity.
They were consequently
strongly dependent on the
listening room’s geometry. In
the end, our model with one
channel sweeping the visual
field from left to right would
maintain the consistency of
timbre, something that our
competition couldn’t provide
by limiting itself to the high
frequencies.
The two pairs of lateral speaker drivers are used for reproducing the bass. Bass-reflex loading with two ports on either side of the soundbar. The frequency response extends to 50Hz despite a limited load of 1.45 litres per speaker driver.
Focal’s innovative solution is
based on the network of five
identical low-directivity speaker
drivers situated on the same
front plane. The work on the
phase on the lateral surround
channels, like an optical lens,
creates an expanded sound field
whilst conserving wideband
timbre coherence.
Classical Surround Management
Dimension Surround Management
Moreover, the centre channel
remains in total coherence
to provide intelligible dialogue, whereas it is usually
moved back to emphasise the
surround effects. We have
succeeded on all points.
Spatialisation no longer
depends on the listening room
and its geometry thanks to a
centre channel, which provides
intelligible dialogue: essential
for truly understanding the
message!
DESIGN AND BASS FREQUENCY
MANAGEMENT
As 50" flat screens are becoming
the minimum standard for a
quality installation, the length
chosen for Dimension was 41/2”
(115mm), which is the width of
a base of such a flat screen.
As pointed out previously, the
thickness is key, mainly when
a wall-mounted installation
is chosen, and it is generally
ideally limited to 21/3” (60mm).
Knowing that the speaker
drivers have a thickness of
17/16” (36mm), the choice of
acoustic load was decisive.
The initial solution to use a
TQWT (tapered quarter-wave
tube) seemed ideal for speaker
drivers with a small diameter in
order to extend the frequency
response of the bass, ideally
50Hz at -3dB.
The first prototypes enabled
us to soon realise that some
modifications were required
because the width of the
soundbar was not sufficient to
unfold the acoustic line to reach
such a frequency. The volume
was also insufficient. We also
considered using a passive
radiator, but eventually opted
for a more classic bass-reflex
solution with side ports.
Thus, we achieved our target
36 Hz avec sub
crossover frequency in the bass
by having a total thickness of
29/16” (65mm) and a load volume
of 1.45 litres per speaker
driver (the centre channel has
a closed load volume of only
0.5L). The solid aluminium
monobloc casing designed in
a U shape brings the rigidity
required to avoid colouration,
which can be caused when
enclosures are submitted to
very high pressures as a result
of the power in such small
volumes as these.
We already had our solution for
the wall mount, so what about
the TV cabinet?
Our first assessment revealed
that the shape of flat screen
stands was differing more and
more. Reducing the height
by inclining the soundbar in
order not to interfere with the
flat screen seemed like a wise
choice. This also directed the
speaker drivers’ axis towards
the listener’s ears on a standard
installation where the central
vertical plan of the screen is
ideally in the spectator’s visual
axis.
Despite this inclination, the
height could not be reduced to
less than 43/4” (120mm), which
was still too high for some
screens. We needed to design a
support. As the size of supports
were increasing more and more
due to the increasing size of
flat screens, the function of the
support was soon diverted…
We turned it into an optional
subwoofer.
Such an available volume is
a dream for any acoustician.
Thanks to the soundbar’s sixth
amplifier channel, a passive
subwoofer could be used. There
are two main advantages to
this: it simplified installation
and use, and it made it more
affordable. A prototype
elliptical speaker driver was
soon designed. The first model
was promising and had deep
bass. There was only one
disadvantage: the vibration
transferred to the screen was
worrying.
A push-push configuration
with two enclosures and two
speaker drivers working in
opposed mode soon solved
the problem. A glass plate
was added to give a strong and
understated high-quality finish.
Zero vibration
50 Hz sans sub
Dimension’s subwoofer has two bass-reflex enclosures with 100% Focal speaker drivers 21/3”
x8” (60x200mm) working in opposite to avoid vibration. When combined with the soundbar, it
offers a frequency response of 36Hz and a maximum SPL of nearly 105dB!
USER INTERFACE AND
ELECTRONICS
In this day and age of
smartphones and connected
devices, the design of the user
interface was fundamental. It is
what makes an object smart. A
control panel needs to be easy
to use, intuitive and discreet it shouldn’t conflict with the
image.
Installation settings were
purposely chosen with
p hys i ca l s w i tc h e s a n d
require configuration before
plugging in. Three settings
are necessary: on wall/free
standing/table; the distance
from the listening position
and the room acoustics: soft/
medium/clear.
An automatic on/off function
with proximity sensing, and a
touch screen was the ideal.
We developed this with an
English agency specialising
in ergonomics. Besides the
source selection and volume
controls, only the ‘Nightmode’
(Dolby Digital message) needed
to be added to the front panel.
The bass can easily be adjusted
using the remote control and
level could be set using the
+/- volume buttons. Simplicity.
Four switches help a simple adaptation to
the environment
For the power amplifiers, we
chose the excellent TDA7498
model. Having already been
used on Bird and more recently
on Easya, it was a product we
were already familiar with.
This very compact amplifier
only requires a single positive
power supply and synchronisation with the built-in clocks to
avoid intermodulation between
sampling rates of the six amplifier channels.
User interface with proximity sensor and touch selection
Sound quality depends largely
on the output filter and on
the quality of power supply.
We chose an external power
supply for obvious reasons
related to space limitations
given our targets in terms of
the soundbar’s dimensions.
Capacitors on the motherboard
situated within direct proximity
of the power module store the
energy necessary to manage
transient modulation peaks.
Powered with 33V, the peak
power is over 75W x 6 channels,
1 channel being dedicated to
Dimension’s passive subwoofer.
Prototype of the electronic board where all
the functions are grouped with the exception of the power supply. On the left, notice
the twelve ferrite bead output filters. In
the centre are the three capacitors which
store energy for managing modulation
peaks.
Knowing that our speaker
drivers have an excellent
sensitivity for such a diameter (89dB/1W/1m), the five
channels combined have a
Sound Pressure Level as high
as 110dB/1m for the soundbar alone and the subwoofer
has an SPL of nearly 105dB.
More than anything, it was the
consequent definition and the
dynamics we were aiming for,
but having power in reserve is
never a bad thing.
The DSP is a key component.
The 4th generation Sharc®
32bit/40bit floating point
DSP is optimised for highperformance audio signal
processing. It brings sufficient
processing capacity for
controlling the balance of
frequency response on the one
hand and the spatialisation of
the five channels on the other.
It acts like a virtual built-in
mastering studio program.
The rules of the art (science)
need to be respected, i.e.
the physical capabilities of
the speaker drivers are not
to be exceeded (they are
downstream of the system
and the coupling with air gives
them a certain inertia). On a
cerebral level, hearing maintains an overall perception of
sound. The brain is not easily
fooled. The DSP will never turn
a mediocre sound system into
a good-quality system.
However, the magic of digital
technology is being able to work
independently on the phase, the
delay between channels and
on the amplitude, something
that is absolutely impossible
with analogue systems. The
latest advances in IIR (Infinite
Impulse Response) filters,
s p e c i f i c a l ly t h e 2 8 - b i t
coefficients in our case, allow
a huge range of settings of
the five channels to adjust
t h e to n a l b a l a n ce a n d
spatial relationships almost
independently to create the
ideal soundscape.We also use
the processing power.
We also use the processing
power of the DSP to mix the
LF signals of the five channels
below 200Hz to generate
a mono signal. This LF
mono signal is sent to the
four lateral channels and
the subwoofer. We can that
way get the equivalent of a
21cm woofer. In addition the
centre channel, working into
a smaller enclosure of 0.5
litres, is protected from any
intermodulation distortion to
ensure definition and maximum
intelligibility.
In addition to the frequency
band above 200Hz, we have
three other frequency bands
adjustable with 12dB/octave
slopes: 40-70Hz; 70 -100Hz and
100-200Hz. This allows a fine
equalizer function depending
on the signal level. So as an
example: with the subwoofer
connected, the compressor
on the 40-70Hz band on the
soundbar limits this level to
increase the overall SPL and
reduce the distortion.
The last point on how our
choices in terms of acoustics
have had an impact on the
electronics concerns the
aluminium monobloc chassis
to ensure maximum rigidity:
implementing a wireless
Bluetooth® receiver was no
longer possible due to the
electromagnetic shielding
of the aluminium chassis.
So we made this an optional
function thanks to our universal
Bluetooth® AptX ® receiver,
which connects to the analogue
mini jack.
In conclusion, we have learnt a
great deal from the Dimension
project:
1. In Europe, we have the ability to compete at the highest
level. This requires collaboration, which is essential to enter
the connected device market,
where electronics and software
play a crucial role.
2. Beyond the design, functions
and use, it is amazing to see
that our focus on these points,
which for some may only seem
like small details, has brought
so much more to the product...
and this coincides with our
passionate beginnings in the
high-end market. Let’s not
forget that acoustics and the
speaker driver in particular are
still mostly analogue!
Gérard Chrétien, 1st March 2014
FOCAL®is a trademark of FOCAL-JMLAB®
Focal-JMlab® - BP 374 - 108, rue de l’Avenir - 42353 La Talaudière cedex - France.
Tél . 33 (0) 477 435 700 - Fax +33 (0) 477 376 587 - © 2013 Focal-JMlab® - SCEB -140327/1
Due to constant technological advances, Focal-JMlab® reserves its right to modify specifications without notice. - Images may not conform exactly to specific product - Photos L’Atelier Sylvain Madelon.
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