JBL LSR6328P User manual

LSR6328P
Linear Spatial Reference
Bi-amplified Studio
Monitor
Key Features:
䉴 Advanced Linear Spatial Reference
design ensures flatter-off-axis response
for greater clarity at the mix position.
䉴 RMC™ Room Mode Correction
provides electronic control of room
modes. User measurement and
calibration kit available.
䉴 Differential Drive®technology with
dynamic braking for extended low
frequency response and minimal
power compression.
䉴 Integrated bi-amplification with
factory calibrated sensitivities.
䉴 Titanium composite high frequency
transducer with elliptical oblate
spheroidal waveguide for precise
pattern control.
䉴 Magnetically shielded high frequency
transducer minimizes interference
when used in close proximity to
video monitors.
䉴 High-Density baffle for high inertial
ground and low resonance.
䉴 Linear Dynamics Aperture port
design eliminates port turbulence
and reduces port compression.
䉴 Reinforced enclosure and convenient
mounting points for mounted
installation.
䉴 Integral handles facilitate ease of
positioning.
The LSR6328P studio monitor is
designed for use in critical stereo and
multi-channel monitoring applications
that require exceptional spectral accura-
cy and high SPL capability. The
LSR6328P combines the latest in JBL’s
renowned transducer and system tech-
nology with psychoacoustically derived
spatial response criteria, resulting in a
more accurate studio monitoring refer-
ence system. In this design process, the
system’s frequency response over the
forward listening range (±15° vertically
and ±30° horizontally) is optimized, as
opposed to the conventional approach
of optimizing the response directly on-
axis. This design approach involved
careful component design, selection of
crossover frequency, and precise baffle
geometry and detail. The result is a sys-
tem that can be used for the most criti-
cal judgements of recording balance,
image placement, and equalization. The
matching of the LSR6328P system to the
listening environment is further
enhanced through the use of RMC, an
analysis/correction system that identi-
fies and corrects response to compen-
sate for the dominant low frequency
standing wave in the system’s room
response. In addition to a rich array of
performance features, the LSR6328P has
a reinforced enclosure and integral
mounting points to facilitate wall mounting. Recessed handles facilitate easy
positioning of the loudspeaker in the environment and aid in transportability.
218F Low Frequency Transducer
The 8" woofer is based on JBL’s patented Differential Drive®technology. With
dual 1.5" voice coils, power compression is kept at a minimum to reduce spec-
tral shift as output power levels increase. An added third coil located between
the drive coils acts as a dynamic brake to limit excess excursion and reduces
audible distortion at maximum levels. The cone is made of a carbon fiber com-
posite forming a rigid piston and is supported by a soft butyl rubber surround.
053TiS High Frequency Transducer
The high frequency transducer has a 1" composite diaphragm integrated with
an Elliptical Oblate Spheroidal (EOS) Waveguide with wide uniform dispersion
that is critical to the smooth spatial response required in today’s working envi-
ronments. The driver is shielded to minimize the interference when used in
close proximity to video monitors.
Bi-amplified Power System
The LSR6328P combines two high power amplifiers with an active dividing
network. Included are over 250 watts of continuous low frequency power and
120 watts for the high frequency section. The active dividing network produces
a 36/dB-per-octave Linkwitz-Riley type response for smooth transition between
transducers, both in the frequency and time domains. This results in exceptional
imaging and a lack of time smear, and the circuitry also yields a tonal-artifact-
free noise floor.
Input Sensitivity and Equalization:
User adjustments include level calibration settings for use with professional
and semiprofessional equipment, as well as fine tuning with variable level trim.
Neutrik “Combi” input receptacles accommodate both XLR and ¼" connectors,
either balanced or unbalanced. DIP switch 1 inserts a variable input trim for up
to 13 dB of input attenuation. DIP switches 2 & 3 allow selection of either
-10 dBV, +4, or +8 dBu calibrated input sensitivities on the ¼" or XLR inputs. A
Very Low Frequency (VLF) high-pass filter provides protection from excess
woofer excursion at maximum playback levels. DIP Switch 4 disables this filter
providing slightly extended deep bass response below the enclosure port tuning
and allowing the user to observe cone motion caused by sub-sonic signal.
Boundary compensation is user-selectable to correct low frequency and mid-
bass build-up when the speakers are placed close to a corner or wall. Three
settings (-1.5 dB, -3 dB, -4.5 dB) are provided using DIP switches 5 & 6. DIP
switches 7 & 8 provide 1.5 dB high-frequency boost and attenuation to allow
compensation for dull or bright listening environments.

䉴LSR6328P Linear Spatial Reference Bi-amplified Studio Monitor
RMC™ Equalization
Through the use of a test CD, sound level meter and Q
template, the user can identify any dominant room mode
over the tuning range from 26 to 96 Hz that effects the LF
response at the listening position. The inverse curve can
then be entered into the system’s electronics – to exactly
compensate the offending peak. Using the RMC
Calibration Kit*, the user is also instructed specifically
what to look for, and potentially poor room locations can
be avoided. RMC kit contains all items required to carry
out the RMC system calibration process. *(Purchased sepa-
rately. Kit is included with each LSR6312SP Subwoofer)
We all know that many loudspeakers have similar mea-
surements but sound different. By going beyond simple
on-axis frequency response measurements, JBL defines the
ultimate performance specification for new systems – what
it will sound like in your room.
While other manufacturers use a single on-axis frequen-
cy response measurement taken at one point in space, JBL
measures monitor systems over a sphere that encompasses
all power radiated into the listening room – in every
direction. This data reflects 1296 times the information of
a single on-axis response curve. Seventy-two measure-
LSR6328P Response Curves
ments of the direct sound field, the reflected sound field,
and the reverberant field, the entire sound field heard by
the listener, is correlated to optimize response at the lis-
tening position. In place of spectral smoothing used by
some manufacturers, which actually conceals data, the JBL
approach actually exposes flaws in systems, such as reso-
nances, poor dispersion and other causes of off-axis col-
oration.
The data shown below is a set of spatially measured
graphs that are the heart of JBL’s philosophy.
Linear Spatial Reference Design and Measurement Techniques
3019665
Conforms to UL STD
6500, Certified to CSA
STD E60065
1. On-Axis Response
2. Spatially Averaged Response
over a range of +/- 30°
Horizontal & +/- 15° Vertical
3. First Reflection Sound Power
4. Total Radiated Sound Power
5. DI of On-Axis Response
6. DI of First Reflections

Notes:
All measurements unless otherwise stated made anechoically in a 4␲environment at 2
meters, referenced to 1 meter by inverse square law.
The reference measurement microphone position is located perpendicular to the cen-
terline of the low and high frequency transducers at the point 55 mm (2.2 in) below
the center of the high frequency diaphragm.
Acoustic loading provided by the listening room increases maximum SPL capability
and low frequency bass extension as compared to stated anechoic values.
Distortion measurements performed with the input voltage necessary to produce the
stated A- weighted SPL at the stated measurement distance. Distortion figures refer to
the maximum distortion measured in any 1/10th octave wide band in the stated fre-
quency range.
JBL continually engages in research related to performance improvements. New mate-
rials, production methods, and design refinements are introduced into existing prod-
ucts without notice as a routine expression of that philosophy. For this reason, any
current JBL product may differ in some respect from its published description, but will
always equal or exceed the original design specification unless otherwise stated.
Specifications:
System:
Frequency Response (+1, -1.5 dB): 50 Hz - 20 kHz
Enclosure Resonance Frequency: 38 Hz
Low Frequency Extension: User controls set to default
-3 dB: 46 Hz
-10 dB: 36 Hz
Low-High Frequency Crossover: 1.7 kHz 6th-order acoustic Linkwitz-Riley
Distortion, 96 dB SPL, 1 m:
Mid-High Frequency (120 Hz - 20 kHz):
2nd Harmonic: <0.6%
3rd Harmonic: <0.5%
Low Frequency (<120 Hz):
2nd Harmonic: <2%
3rd Harmonic: <1%
Maximum SPL (80 Hz - 20 kHz): >108 dB SPL / 1m
Maximum Peak SPL (80 Hz - 20 kHz): >111 dB SPL / 1m
Signal Input: Neutrik “Combi” XLR-¼-in tip-ring-sleeve balanced or unbal-
anced positive voltage applied to XLR pin 2 (¼" tip) produces
outward woofer motion
Calibrated Input Sensitivity, XLR & ¼":
+4 dBu / +8 dBu: 96 dB SPL / 1 m
-10 dBV: 96 dB SPL / 1 m
AC Input Voltage: 100 /240 VAC, 50/60 Hz (auto sensing)
AC Input Connector: IEC
Long-Term Maximum System Power: 220 watts (IEC265-8)
Self-Generated Noise Level: <10 dBA / 1 m Tonal-artifact-free noise floor
User Controls:
High Frequency Control (2 kHz - 20 kHz): +1 dB, 0 dB, -1 dB
Low Frequency Control (< 100 Hz): 0 dB, -2 dB
Low Frequency Alignments: 36 dB/octave, 24 dB/octave (VLF protection off)
Calibrated Input Sensitivity: -10 dBV, +4 dBu, +8 dBu
Boundary Compensation Settings: 0, -1.5, -3.0, -4.5 dB
Variable Input Attenuation: 0 dB to -13 dB
RMC External Bypass: ¼" jack
RMC Active Switch: In/Out
RMC Frequency Adjust: 26 Hz - 96 Hz (10th octave, 18 centers)
RMC Depth Adjust: 0 - 14 dB (cut only)
RMC Q Adjust: 1/20th to 1/2 octave, 21 steps
Transducers:
Low Frequency Model: 218F
Diameter: 203 mm (8 in)
Voice Coil: 38 mm (1.5 in) Differential Drive®with dynamic braking coil
Magnet Type: Ferrite, with integral heat sink
Cone Type: Carbon fiber composite
Impedance: 2 ohms
High Frequency Model: 053TiS
Diameter: 25 mm (1 in) diaphragm
Voice Coil: 25 mm (1 in)
Magnet Type: Ferrite, shielded
Diaphragm Type: Damped titanium composite
Other Features: Elliptical oblate spheroidal waveguide
Impedance: 4 ohms
Amplifier:
Low Frequency:
Topology: Class A-B, all discrete
Sine Wave Power Rating: 250 watts (<0.1% THD into rated impedance)
THD + N, ½Power: <0.05%
High Frequency:
Topology: Class A-B, monolithic
Sine Wave Power Rating: 120 watts (<0.1% THD into rated impedance)
THD + N, ½Power: <0.05%
Physical:
Finish: Smooth dark graphite
Handles: 2 each, flush mounted on sides
Mounting: 4 threaded mounting points conforming to industry standard
square pattern, 127 x 70 mm (5 x 2.75 in) center to center. M6
metric threads.
Enclosure Volume (net): 28 liter (1 cu ft)
Low Frequency Vent: Rear ported linear dynamics aperture (integrated with
amplifier heat sink)
Baffle Construction: Injection-molded structural ABS
Enclosure Construction: 19 mm (¼in) MDF
Net Weight: 17.7 kg (39 lb)
Dimensions (HxWxD): 406 x 330 x 325 mm (16 x 13 x 12.8 in)
Caution: Unsafe mounting or overhead suspension of any heavy load can result in serious injury and equipment
damage. Mounting of speakers should be done by qualified persons in accordance with all applicable local safety
and construction standards. Be certain to follow the instructions provided by the manufacturer of the mounting
bracket. Before selecting a mounting bracket, be certain that it is capable of supporting the weight of the speaker
to be mounted.
96 dB/1 m (Distortion raised 20 dB)
102 dB/1 m (Distortion raised 20 dB)
Amplitude & Phase
2nd
3rd
2nd
3rd

䉴LSR6328P Linear Spatial Reference Bi-amplified Studio Monitor
SS LSR6328P
CRP 5M
8/05
Impulse Response
Acoustic Contribution
JBL Professional
8500 Balboa Boulevard, P.O. Box 2200
Northridge, California 91329 U.S.A.
© Copyright 2005 JBL Professional
A Harman International Company