JBL K2 S9900 User manual

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Project K2 S9900
Product Commentaries
and User Guide
Thank you for purchasing the JBL®Project K2 S9900 loudspeaker system.
Before using the system, please take the time to read through this user guide
to understand this product well and also to use it properly.
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Table of Contents
Preface…5
Chapter 1
Legacy…7
Chapter 2
Project K2 S9900…11
Chapter 3
Unpacking…21
Chapter 4
Selecting Cable…23
Chapter 5
Amplifier Recommendations…25
Chapter 6
Placement and Setup Considerations…27
Chapter 7
Switch Operations…29
Chapter 8
Connections…33
Chapter 9
Care and Maintenance…37
Chapter 10
Troubleshooting and Service Guide…39
Project K2 S9900 Specifications…41
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PREFACE
Thank you for selecting the Project K2 S9900 loudspeaker system. It represents
the culmination of extensive research and development in sound reproduction
over the last half century. JBL engineers have labored to create a loudspeaker
system with no acoustical or electrical limitations whatsoever. While the
Project K2 S9900 is itself a new development, the goal that it achieves goes
back to the earliest days of the original James B. Lansing Sound Company.
However, it is the level of your listening pleasure that ultimately determines
how successful this endeavor is.To ensure a perfect listening experience, you
are asked to carefully follow the setup and operation procedures outlined in
this Project K2 S9900 user guide.
This manual serves several purposes. It contains all necessary background
information and detailed instructions for setting up your Project K2 S9900
loudspeaker system, including unpacking the loudspeaker, selecting the correct
location, speaker wire, wiring method and amplification, and connecting it to its
associated electronics.This information will be found in Chapters 3 through 8.
In addition, a detailed description of your Project K2 S9900 loudspeakers is
included (Chapter 2) so that you may become thoroughly acquainted with the
unique design and technical features.
Despite the formidable nature of the Project K2 S9900, the setup procedure for
this loudspeaker system is relatively simple.Again, you are strongly urged to
read this manual thoroughly before you begin, and then consult it frequently
throughout the process. Certain considerations must be made in placing the
speakers; their physical characteristics make it imperative that you become
familiar with the entire setup process in advance.
Also, the historical and technical information included will add immeasurably
to the complete enjoyment of your system. Project K2 S9900 is unparalleled in
the field of sound reproduction.The story and principles behind it are an
interesting, informative and fitting start to a lifetime of musical enjoyment.
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CHAPTER 1
Legacy – the Historical Development of the JBL Project Loudspeakers
Of those who have sought perfection in sound reproduction, only a few have
actually come close. For one thing, it is a costly process. It is rare indeed when
an individual or group is able to triumph over the constraints of economic and
technological realities even once.
At JBL, Inc., this has happened eight times. In each case, JBL engineers were
told to build the speaker system they had always wanted to build. Whatever
resources were required would be made available.Thus began an ongoing search
for new frontiers in sound reproduction, beginning in the mid-1950s and
continuing to the present day.
The results of this venture are now known as the JBL Project loudspeakers.
Each model represents the absolute peak of every technological, material and
engineering innovation available at the time, combined into a single system.
They are the Hartsfield, Paragon, Project Everest DD55000, K2 S9500/7500,
K2 S5500, K2 S9800, K2 S5800 and, most recently, Project Everest DD66000.
Although differing in performance details and physical attributes, all of the
Project loudspeakers have shared a common objective – to elevate sound
reproduction to levels defined only by the limitations of existing materials and
technology.The fact that all Project speakers have many common features –
despite a spread of nearly 60 years – is a testimony to the excellence of the
technology and manufacturing techniques upon which the JBL brand was built.
The K2 S9900 continues this trend.
Defining the Project Concept
The Hartsfield beganaJBLtradition that continuestoday. First, engineer aproduct
as close to perfection as possible.When it reaches that level, make it better.
In1954, theHartsfieldwassignificantinrepresentingnot new technology,
but ratheranew level of technicalmanufacturing, inthespiritoftheapproach
pioneered by JamesB.Lansingsome20yearsbefore. Like itsProjectseries
successors, itwas a high-efficiency systemincorporating compression driver
technologyand combining thequalitiesofhigh-output,low-distortion,
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exceptionalstereoimagingandfatigue-freelistening.Mostimportant, itwas the
firstloudspeakersystem availabletoconsumers todoallthis.
Project K2 S9900, oneofthe mostadvanced andsophisticatedloudspeakersin
the worldtoday, isthelatestexpressionintechnologythatisdeeply rootedinmore
than60yearsoftradition.WilliamThomas,JBL president in 1954,described the
Hartsfieldasthe “speakersystem we havealwayswantedtobuild[with]the finest
components ever made available to serious listeners.”
He went on to describe the process behind the creation of the Hartsfield:
“Most people whoownand appreciatefine soundreproductionequipmentlook
forward totheday when they will be abletoassemblea systemwithout limitation
in just exactly the way they think it should be done. Periodically, a manufacturer
gets this same feeling....The science of acoustics has provided us with the basic
principlesavailabletoall for achievingprecisionreproduction. Itisonly a matter
ofincorporatingthesemethods into a system design, andthentakingeverybit of
troublenecessarytobuild asystemprecisely tothedesign.”
Headded,“It isn’teasy, but that’stheway itisdone.”
The Ranger-Paragon, the second JBL Project system, was the first serious attempt
atareflectingspeakersystem,andbroke ground in thenew concept ofstereo
imaging.Basically twoindependentfull-rangespeaker systemsinstalled ina
handsome, curvedcabinet nearly9 feet(2.7meters)long, theParagon’s enclosure
wastreatedasanextension ofitstransducers. Inessence,thesystem hadits
own “built-in acoustics.” In many respects, the Paragon anticipated loudspeaker
developmentsthatwouldoccur years, andeven decades, later.This“built-in
acoustics”concept ispresent in theProject K2 S9900.
Fornearly30years,the Paragon,along withtheHartsfield, remainedamong the
most sought-afterspeakers in the world. In 1986, a new Project system was
introduced that retained the Paragon’s overall sense of musicality while upgrading
its character by incorporating three decades’worth of continuous development in
every facet of its design. Its name – Project Everest – reflected the pinnacle of
achievement it represented.This was the original Project Everest DD55000.
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For the first time, the rest of the sound reproduction chain – and not the
loudspeaker or its transducers – would impose limits on overall system
performance. Like the Paragon and Hartsfield, the K2 S9900 was built around
compression driver technology and addressed a more refined stereo image
than was previously considered technically feasible.
Since the original Project Everest was introduced, sound recording and
playback technology has undergone a revolution of its own. With the advent
of the CD, extremely demanding recorded signals became the rule rather than
the exception; the typical source material used by the average audio enthusiast
was superior to the best demonstration material of even just a few years prior.
In overall dynamics and transient response, transducers became once again a
potentially weak link in the high-end audio reproduction chain.
It was in this environment that JBL engineers set out to create the fourth and
fifth Project loudspeakers, K2 S9500 and K2 S5500.As with the Hartsfield,
the simplicity of a two-way system was considered the most promising design
track.Advances in transducer design and low-frequency alignment would make
possible the construction of a two-way system of unprecedented physical and
acoustical scale. JBL engineers took the core components – the low- and
high-frequency drivers – and optimized them by redesigning their magnetic
structures, diaphragms and framework for greater linearity, dynamic capability
and transient response.
In the years following the introduction of the K2 S9500 and K2 S5500, sound
reproduction technology underwent another series of revolutionary changes,
with the introduction of DVD-Video, Dolby®Digital, DTS,®DVD-Audio and
SuperAudio CD (SACD™) media. Frequency responses to 50kHz, as well as
three-digit dynamic range and signal-to-noise ratios, have now become com-
monplace. In order to faithfully reproduce such robust sonic properties, the
loudspeaker needed to undergo drastic improvements to its transducer, network
and enclosure technologies.
The K2 S9800 employed a three-way design, incorporating an ultrahigh-
frequency (UHF) compression driver and horn to reproduce high frequencies
up to 50kHz. With the UHF driver handling the higher frequencies, the high-
frequency (HF) transducer could then be upgraded to a new design using a
3-inch (75mm) diaphragm for better reproduction of lower frequencies and
to blend better with the woofer than the older-generation 2-inch (50mm)
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diaphragm did. Both compression drivers utilized newly developed beryllium
diaphragms to provide the lowest distortion and flattest frequency response
possible.
In order to re-create the extremely high dynamic range provided by today’s audio
sources, a brand-new low-frequency transducer was developed from the ground
up, utilizing an alnico magnet, a 4-inch (100mm) edge-wound voice coil, and a
15-inch (380mm) cone. Extensive computer-aided engineering and design effort
were necessary to develop the optimized port tuning used in Project K2 S9800,
and has resulted in a significant advance in the concept of state-of-the-art
acoustic reproduction.As a result of the K2®efforts, a speaker system with
higher sensitivity and a wider dynamic range became a reality without power
compression or distortion, even at extremely high drive levels.
The K2 S9900 continues the tradition of the K2 S9800 and also incorporates
key design elements from the DD66000. Despite its 21st century power and
sophistication, Project K2 S9900 is a synthesis of tradition and technology.
It reflects the design, material, engineering and manufacturing expertise
developed and refined through nearly six decades of experience that are
the exclusive legacy of one loudspeaker brand – JBL.
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CHAPTER 2
The Project K2 S9900 Loudspeaker – aTriumph inAcoustics and
Technology
The following sections describe the primary features and components of the
Project K2 S9900 loudspeaker system.
The basic system configuration is what has been referred to historically as an
augmented two-way. In the 1950s and 1960s, JBL engineers primarily built
two-way systems with a 12- or 15-inch (300mm or 380mm) woofer crossed over
to a large-format compression driver/horn combination. Some of the systems
would be “augmented” by a UHF device, usually the 075 ring radiator which
would operate above 8kHz.These systems would have only a single crossover
point in the middle of the audio range, to minimize any sonic degradation
caused by the dividing network.The K2 S9900 has a single midrange crossover
at 900Hz, blending one 1500AL-1 woofer to the 476Mg compression driver and
horn combination.The 045Be-1 UHF driver is brought in at 15kHz to cover 2
octaves of ultrasonic frequencies.Above 900Hz, the HF compression driver and
horn combination operates unassisted, all the way to 20kHz (Fig. 1).
Figure 1. On-axis response of the K2 S9900 system and of each of the
transducers through its crossover network (2.83V @ 1m).
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The transducers, horns and crossover networks are housed in a visually stunning
enclosure that is reminiscent of both the DD66000 and K2 S9800 systems.The
specially curved baffle provides the sidewalls for the main horn.The top and
bottom horn flares are accomplished by the attachment of precision-molded
SonoGlass®horn “lips” to the upper enclosure surface.The UHF driver is
mounted to a SonoGlass horn which is itself mounted to the back of the
die-cast aluminum housing.
The entire enclosure is constructed with 1-inch (25mm) MDF.The complex
bracing is used to precisely hold the curved panels in exactly the correct shape,
allowing exceptional fit and consistency.
The woofer baffle is 1-inch thick and is tied into perimeter bracing, constituting
an extremely rigid and secure structure.A painted outer baffle is then applied,
surrounding the woofer frame, giving the total combined woofer baffle a
thickness of 1-3/4 inch (45mm).The outer baffle is removable to enable repair
or replacement of the painted surface, should that ever be necessary.
The system is ported on the rear with a tuning frequency of 35Hz.A large
4-inch (100mm)-diameter flared port is combined with the input connections
on a massive die-cast aluminum structure.The entire enclosure rests on four
stainless-steel foot assemblies. Stainless-steel coasters are included to protect
wood and tile floors from damage from the spike feet.The grille assembly is
constructed of fiberglass-reinforcedABS to provide the curved shape.The
grille is securely attached to the enclosure with metal pins and rubber cups.
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045Be-1 UHF Driver
HF Network
Spiked FootAssembly
LF Network
Die-CastAluminum Input
Plate/PortAssembly
1500AL-1 (380mm) LF Driver
UHF Network
476Mg 4" (100mm) HF Driver
SonoGlass HF Horn
Die-CastAluminum Housing
SonoGlass UHF Horn
Figure 2.
The 1500AL-1 and 476Mg are both designed to be absolute-minimum-distortion
drive units.Although they are capable of tremendous acoustic output, they are
designed to be completely linear in every way, up to a reasonable drive level.
This enables the system to sound the same, regardless of playback level.
Tr a n s d u c e r s
The 1500AL-1 Low-Frequency Driver
The 1500AL-1 low-frequency driver is very similar to the 1500AL used in
the K2 S9800 system.The voice coil length has been increased to 25.4mm
(from 20.3mm) and its milling width has been reduced slightly.This was done
to allow greater clearance from the outer diameter of the coil to the laminated
top plate and to provide a larger surface area of coil surface for heat dissipation.
The coil former perforations have been eliminated to allow greater forced
convection cooling from the pumping action of the diaphragm assembly.These
coil improvements allow the 1500AL-1 to handle up to 25 percent more power
than the 1500AL (Fig. 3).
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High-Current and
Fatigue-Resistant
Pigtail Leads
Extruded-Aluminum
Spider Spacer
Dual Inverted
Nomex Spiders
Cone Body:
Special Paper-
Pulp Composite
VGC – Vented Gap
Cooling Channels
Voice Coil:
Aluminum RibbonWire on
High-Temp Fiberglass Former
Dust Dome:
Paper-Pulp Composite
EPDM-Foamed
Rubber Surround
Glass-FilledABS
Terminal Base
5-Way Gold-Plated
Terminal Posts
Conductive Ring:
Extruded 6063
Aluminum
Magnet:
Alnico 5DG
Pot:
SAE-1008
Polepiece:
SAE-1008 Steel
Gap Sleeve:
SAE-1008 Steel
Rear Cover:
Cast 380Aluminum
Copper and Steel
Gap Ring Laminations
Frame:
Cast 380Aluminum
Figure 3. 1500AL-1 section view.
The 1500AL-1 low-frequency driver is a 15-inch (380mm)-diameter device with
a 4-inch (100mm) voice coil completely immersed in a radial field generated by
an alnico 5DG magnet.Alnico was chosen because of its stable operating point.
This material is insensitive to temperature changes and back EMF from the coil.
JBL engineers have overcome the tendency of alnico to demagnetize with high
drive, by utilizing a massive shorting ring at the base of the motor assembly.The
top plate is constructed of alternating copper-steel laminations.The presence of
the copper rings linearizes the magnetic properties of the gap to all but eliminate
eddy current distortion.
The outer suspension is made of EPDM-foamed rubber, which has the longevity
and frequency response characteristics of traditional rubber surrounds, but with
a low density very close to that of foam surrounds. Low-loss EPDM material
was chosen so that the transient detail of musical signals could be preserved.
Dual inverted Nomex®spiders are employed for the cancellation of even-order
distortion components.All suspension elements are tailored for maximum
mechanical displacement linearity.
The cone consists of a special layered paper-pulp matrix with proprietary
Aquaplas damping, which offers more pistonic behavior throughout the
woofer’s operating bandwidth, and controlled cone breakup beyond it.
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A thick-wall, cast-aluminum frame is used to rigidly support the motor
structure.This fully vented frame and motor design also serves to minimize
the back pressure under the dome and spider, helping to reduce harmonic
distortion to even lower levels. Proprietary JBLVented Gap Cooling™(VGC) is
incorporated within the motor structure, and lowers the operating temperature
of the coil during moments of high-power operation.
All together, these design factors provide reduced harmonic distortions at
very low and very high acoustic output, improved power handling, reduced
power compression and more consistent spectral balance, with varying input
drive level.
476Mg High-Frequency Compression Driver and Bi-Radial®Horn
The 476Mg high-frequency compression driver makes use of a 4-inch
(100mm)-diameter, magnesium-alloy diaphragm with a 4-inch (100mm)
aluminum edge-wound coil, operating into the JBL existing rapid-flare-type,
coherent-wave phasing plug.The use of an efficient neodymium rare-earth
motor structure with a new copper-sleeved polepiece maintains maximum gap
flux and reduced coil inductance at a minimal size and weight.The combination
of these features has resulted in a driver that can deliver superior sound quality,
regardless of acoustic power output, with very little distortion and power
compression (Fig. 4).
Back Plate
Neodymium Magnet
Copper-Sleeved Pole
100mmAluminum
Edge-Wound Coil
Gap:Acoustic Seal and
ResonanceTuning Ring
Die-CastAluminum
Front Cover
Coherent-Wave, 4-Slot
Phase Plug
Top Plate
Die-CastAluminum
Back Cover
5-Way, Gold-Plated
Terminals
Diamond Surround
Foam Damping Pad
Magnesium-Alloy
DiaphragmAssembly
Figure 4. 476Mg section view.
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A high-purity copper sleeve is used for the polepiece.This greatly improves
the electrical conductivity of the copper sleeve for lower coil inductance and
thus greater high-frequency output at 15kHz and above.The copper-sleeved
pole quickly wicks away heat generated by the coil, thereby contributing to
a reduction in dynamic power compression.To compensate for the higher
resistance caused by the use of a copper-sleeved polepiece, a large magnet
area has been used, in conjunction with special high-grade and high-temperature-
grade neodymium.
The phasing plug is a traditional JBL rapid-flare, coherent-wave four-slot design.
This coherent-wave design shapes the wave output, producing a truly coincident
wave front as the sound enters the Bi-Radial horn.The diaphragm is formed
of magnesium-alloy foil and is the first JBL large-format 100mm compression
driver to use this special material. Magnesium alloy is essentially 95 percent
pure magnesium with small percentages of aluminum, zinc and other alloys
added to improve characteristics such as diaphragm forming, fatigue strength,
corrosive and acoustic properties.A proprietary thermal process is used to
form the thin sheets of magnesium alloy into the 100mm diaphragm shape
of exacting dimensions.This new process even enables the integrated JBL
Diamond surround to be formed as one piece with the dome. Forming the
diaphragms out of sheets of this magnesium-alloy foil yields greater reliability
and resistance against fatigue and corrosive failures than diaphragms formed
with 100 percent pure magnesium or aluminum.
Magnesium has very low density, slightly lower than even that of beryllium.
With such a low density, the thickness of the magnesium-alloy diaphragm could
be greatly increased while still maintaining an equivalent diaphragm mass of
approximately 3.4 grams, similar to previous designs using aluminum and
titanium. Based on this, the new magnesium-alloy diaphragm was increased
to 130 micron, about 1.7 times thicker than the standard 76-micron-thick
aluminum diaphragm. When compared to the titanium diaphragm used in the
original K2 S9500 and M9500 systems, this new magnesium-alloy diaphragm is
2.5 times thicker.This is beneficial because a thicker diaphragm creates a much
stiffer diaphragm, which pushes pistonic behavior to higher frequencies than
current aluminum or titanium diaphragms (given the same moving mass).
Better pistonic behavior means less diaphragm modal breakup at the critical
mid-band frequencies, and so the upper frequency response will be smoother
with minimal distortion spikes.The effects of this will be less distortion, and
improved and extended frequency response (Fig. 5).
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Another benefit of the magnesium alloy is the greater internal loss, or damping,
when compared to titanium or even aluminum.This greater internal loss
quickly minimizes the amplitude of resonances when the diaphragm is asked
to reproduce frequencies beyond its pistonic limit.To further augment this
damping, a very light application of JBLAquaplas is also used. Combining the
greater internal loss with the stiffer characteristics of the thicker, low-density
material, this new 100mm magnesium-alloy dome sonically performs close
to the beryllium diaphragm used in the 476Be high-frequency Project Everest
drive unit, but at a fraction of the cost. In the end, careful optimization of this
new magnesium-alloy diaphragm’s characteristics, along with the application
ofAquaplas damping, has maintained the enhanced detail of musical transients
and microdynamic nuances to which JBL listeners have become accustomed.
Figure 5.Terminated tube measurement of 476Mg with distortion products.The
measurement was made with 7.5V applied to the driver.This equates to about
120dB @ 1m when mounted in the system.
045Be-1 Ultrahigh-Frequency Compression Driver and Bi-Radial Horn
Like the original 045Be, the 045Be-1 uses a 1-inch (25mm) beryllium
diaphragm and 2-inch (50mm) neodymium magnetic structure. The pure-
beryllium diaphragm is less than 0.04mm thick and has a mass of only 0.1 gram.
The single-layer aluminum-ribbon voice coil is wound without a former and is
attached directly to the diaphragm.The driver employs the smallest annular-slit
phasing plug that JBL engineers have ever designed.The 045Be-1 has been
designed to improve manufacturing yield and consistency. Small changes have
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been made to the top plate, and some significant improvements were made to the
surround shape and clamping methodology.As a result, the driver has picked up
nearly 5dB of increased output above 30kHz.A section view of the 045Be-1
driver is shown in Figure 6.
Aluminum-
Alloy Cover
Aluminum
Edge-Wound
Voice Coil
1" (25mm)
Pure-Beryllium
Diaphragm
Stainless-
Steel
Mounting
Bracket
Phase Plug
Neodymium
Magnet Gold-Plated
InputTerminal
Figure 6. 045Be-1 section view.
The extremely low mass of the moving system, high magnetic-flux density and
high rigidity of beryllium produce response that is very smooth from below
8kHz to beyond 50kHz.
The response curve has a slight downhill tilt, due to the constant-directivity
nature of the horn used in this system.The Bi-Radial horn is properly scaled to
maintain a coverage angle of 60 degrees in the horizontal plane and 30 degrees
in the vertical plane over the frequency interval from 10kHz to 50kHz.
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Internal Crossover Network
The circuit topology, combined with the acoustic behavior of the 1500AL-1 and
476Mg, provides a 24dB-per-octave transition at 900Hz.This is the primary
crossover point of the system.Additionally, the 045Be-1 is turned on above
15kHz to provide extended response to beyond 50kHz.
All of the electrical components are of the highest quality and exhibit the
lowest internal loss.The inductors used are “air core” so as not to introduce
nonlinear hysteresis effects. Capacitors are constructed using polypropylene foil,
which is known for having minimal distortion caused by dielectric absorption
nonlinearities.The low-, high- and ultrahigh-frequency networks employ battery
bias to operate the capacitors effectively in a ClassA mode. Every attempt
is made to present as smooth a system impedance as possible to the driving
amplifier.This design element is often overlooked in many loudspeaker
systems, yet amplifiers work their best when they are given smooth, level
load impedance in which to deliver current (Fig. 7).
Figure 7. K2 S9900 system impedance.
The aggregate of these attributes allows the K2 S9900 system to translate
the electrical signal from source material into an accurate and unencumbered
three-dimensional sound field. The system can do this at any desired listening
level, from whisper-quiet to big-band loud, while at the same time maintaining
unchanged acoustic characteristics.
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