Nominal Basket Diameter: 18 in., 457 mm
Nominal Impedance*: 4 or 8 ohms
Power Rating**: 500 Watts
Music Program: 1000 Watts
Resonance: 28Hz
Usable Frequency Range***: 37Hz-250Hz
Sensitivity: 96dB
Magnet Weight: 67 oz
Gap Height: .38 in.,9.53 mm
Voice Coil Diameter: 2.5 in., 63.5 mm
Thiele and Small ParametersResonant Frequency (fs): 28Hz
DC Resistance (Re): 5.3
Coil Inductance (Le): 3.43mH
Mechanical Q (Qms): 10.38
Electromagnetic Q (Qes): .33
Total Q (Qts): .32
Compliance Equivalent Volume (Vas): 493.19 ltr/17.41 cu. ft.
Peak Diaphragm Displacement Volume (Vd): 796.00cc
Mechanical Compliance of Suspension (Cms): .25mm/N
BL Product (BL): 18.9 T-M
Diaphragm Mass inc. Airload (Mms): 128.1 grams
Efficiency Bandwidth Product (EBP): 84
Maximum Linear Excursion (Xmax): 6.7mm
Surface Area of Cone (Sd): 1188.0cm
Maximum Mechanical Limit (Xlim): 15.0m
Mounting InformationRecommended Enclosure Volume:
- Sealed: N/A
- Vented: 85-297 ltr/3.0-10.5 cu. ft.
Overall Diameter: 18.00 in., 457.20 mm
Baffle Hole Diameter: 16.57 in., 420.88 mm
Front Sealing Gasket: Fitted as Standard
Rear Sealing Gasket: Fitted as Standard
Mounting Holes Diameter: .28 in., 7.11 mm
Mounting Holes B.C.D.: 17.25 in., 438.15mm
Depth: 8.13 in., 206.50mm
Net Weight: 17.00 lbs, 7.71 kg
Shipping Weight: 20.5 lbs, 9.3 kg
Materials of ConstructionCoil Construction: Copper
Coil: Polyimide
Magnet Composition: Ferrite
Core Details: Vented and Extended
Basket Materials: Die-Cast Aluminum
Cone Composition: Paper
Cone Edge Composition: Cloth
Dust Cap Composition: Solid Composition Paper
* Please inquire about alternative impedances.
** Multiple units exceed published rating evaluated under EIA 426A noise source and test standard while in a free-air, nontemperature-controlled environment.
*** The average output across the usable frequency range when applying 1W/1m into the nominal impedance. Ie: 2.83 V/8 ohms, 4 V/16 ohms.
- Dimensions and Weight in Packaging
- Blemished, 4 Ohms
-
Shipping Weight: 19.75 lbs
-
Shipping Dimensions: 20 x 19 x 9 in
-
Manufacturer Part Number (MPN): Delta Pro-18C
- 8 Ohms
-
Shipping Weight: 19.25 lbs
-
Shipping Dimensions: 20 x 20 x 9 in
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Manufacturer Part Number (MPN): Delta Pro-18A