Technical Data - Harman JBL Arena X Mode D'emploi

VENTED ENCLOSURES
A vented enclosure acts like a sealed enclosure at frequencies
above its tuned (resonance) frequency. At resonance (which is
defined by the vent), the vent produces the majority of sound- the
subwoofer cone is nearly stationary while the air inside the vent
vibrates. This provides greater mechanical power handling at and
above resonance, but reduced mechanical power handling below
resonance. Since the subwoofer cone and voice coil do not move
much at resonance, airflow across the voice coil is minimized and
thermal power handling is reduced slightly at resonance.
Vented enclosures provide better efficiency in the 40Hz – 60Hz
EN
range, at the expense of sound output in the lowest octave (below
40Hz). The use of an infrasonic filter is recommended with vented
enclosures. An optimum vented enclosure for a Series subwoofer
is larger than an optimum sealed enclosure.
VENTED-ENCLOSURE
PERFORMANCE ADVANTAGES
• An optimum vented enclosure has greater efficiency and higher
output in the 40Hz – 60Hz range than an optimum sealed
enclosure.
• An optimum vented enclosure provides a greater sensation of
bass than an optimum sealed enclosure.
• A subwoofer in an optimum vented enclosure will require less
amplifier power to achieve a given acoustic output (down to
the enclosure's resonance frequency) than in an optimum
sealed enclosure.
VENTED-ENCLOSURE
PERFORMANCE TRADE-OFFS
• Reduced output in the lowest octave (below 40Hz).
• Reduced mechanical power handling below the enclosure's
resonance frequency. The use of an electronic infrasonic filter is
strongly recommended to reduce the chance of overdriving the
subwoofer below the enclosure's resonance frequency.
• An optimum vented enclosure will always be larger than an
optimum sealed enclosure.
VENTED-ENCLOSURE
CONSTRUCTION
Vented-enclosure construction is more difficult than the
construction of a sealed enclosure. The enclosure volume and
port dimensions have a specific relationship with the physical and
electromechanical characteristics of the subwoofer, requiring that
the recommended enclosure volume and port characteristics be
strictly observed. As with sealed enclosures, use medium-density
fiberboard (MDF), glue and screws to construct the enclosure, and
seal all joints with silicone caulk.
RECOMMENDATION
Subwoofers in vented enclosures are recommended for
enthusiasts who prefer accentuated bass response, for those who
have plenty of cargo space to devote to a subwoofer enclosure
and for those who will use a less powerful amplifier to drive their
subwoofer. The volume and port dimensions indicated must be
followed precisely to ensure optimum performance.
MOUNTING THE SUBWOOFER
The subwoofers should be mounted from the outside of the
enclosure. Use the included foam mounting gasket to ensure a
leak-free seal between the subwoofer frame and the enclosure.
CONNECTING THE AMPLIFIER
The subwoofer connectors are compatible with bare wire ends.
The recommended wire gauge is between 14AWG and 8AWG,
depending on the length of the wire run between the amplifier and
woofer. Heavier gauge wire is preferred for runs over 6' (2m).
To connect the speaker wire coming from your amplifier, push
down on the terminal to expose the connection hole. Thread
the bare wire end through the hole, then release the terminal to
secure. Be sure to observe proper wire polarity for maximum
performance.

TECHNICAL DATA

THIELE-SMALL PARAMETERS
Voice coil DC resistance:
Voice coil inductance @ 1kHz:
Driver radiating area:
Motor force factor:
Compliance Volume:
Suspension compliance:
Moving mass, air load:
Free-air resonance:
Mechanical Q:
Electrical Q:
Total Q:
Magnetic-gap height:
Voice coil height:
Maximum excursion:
R (OHMs) 1.56
EVC
L (mH) 0.9
EVC
S (IN ) 76.085
2
D
S (CM ) 490.87
2
D
BL (T ) 10.287
M
V (FT ) 2.203
3
AS
V (Liters) 57.345
AS
CMS (µM/N) 168
M (Grams) 223.241
MS
F (Hz) 26
S
Q 8.813
MS
Q 0.537
ES
Q 0.507
TS
H (IN) 0.394
AG
H (mm) 10
AG
H (IN) 1.57
VC
H (mm) 40
VC
X (IN) 0.591
MAX
X (mm) 15
MAX