Subwoofer OWNER'S MANUAL AND INSTALLATION GUIDE SPL 15, SPL 160

8
SUGGESTED ENCLOSURES
Infinite Baffle
• Excellent performance for all types of music at moderate levels
Sealed
• 1.5 ft
3
- Good linear response, excellent small enclosure.
Excellent for high SPL, multiple driver applications.
• 2.0 ft
3
- Good linear response, excellent all around
enclosure.
Vented
• 3.25 ft
3
@ 27 Hz (Two 4" x 19.75" ports) - High output with
good low frequency extension. Good small enclosure.
• 6.7 ft
3
@ 21 Hz (Two 4" x 15" ports) - High output with
excellent low frequency extension. Great for Rock music
or home theater applications.
Sealed (S)
Vented (V)
5
which is tuned to resonate at a specific frequency.
Sealed Bandpass Enclosure
Sealed bandpass enclosures enclose both sides of the
woofer(s). An airtight enclosure is built around the front and back of
the woofer and one
chamber is ported to
a specific frequency.
CALCULATING (NET) INTERNAL ENCLOSURE VOLUMES
When constructing any type of enclosure, you must be aware that the
outside dimensions DO NOT represent the true (Net) volume inside.
Such things as woofers, ports, thickness of enclosure material, dividing
walls, and any internal bracing will reduce the total amount of the
actual air space available. The following worksheet has been designed
to provide you with the necessary steps to accurately calculate the
absolute (Net) internal volume of any given enclosure.
Calculating Cylindrical Port Volume
1. Measure the outside diameter of the port and divide by 2 for the
radius.
2. Square the radius and multiply by 3.14 (π) to arrive at outside port
area.
3. Multiply the area by the length of
the port inside the enclosure for the
port volume.
outside
diameter
length inside
enclosure
Pros Cons
• High power handling
within the operating
frequencies
• Very high output within
the range of the oper-
ating frequencies
• Low power handling
beyond the tuning
frequency
• Poor to moderate
transient response
• Poor low frequency
extension
SEALED BANDPASS