1.21"LF loud speaker 2.subwoofer speaker 3.1200Watt RMS,98dB 4.6 inch voice coil,330mm magnet 5.23-900Hz frequency response

6. terrific LF loud speaker for  subwoofer of compass bass relex

7 Reasonable price for a 21" speaker like this which delivers good bass sound.This model is a new model with unique design and great power.

8.Hipower Audio is a professinal loud speaker factory with experience in the speaker field for 8 years. We make our own tranducers ,HF drivers and empty cabinets.

9. Pro sound, Pa audio , speaker system, speaker enclosure,professional speaker

10. OEM service is available

General Specifications
Nominal Diameter	530/21	mm/inch
Rated Impedance	8	ohm
Nominal Power handling1	1200	Watts
Program Power2	2400	Watts
Sensitivity(lw/lm)3	98	dB
Frequency Range4	23-900	Hz
Minimum Impedance(Zmin)	9.3	ohm
Voice Coil Diameter	150/6	mm/inch
Voice Coil Material	Copper
Voice Coil Winding Depth	30	mm
Number of layers	4(inside/outside)
Magnet gap depth	12	mm
Surround Shape	Tripple-roll
Basket	CastAluminum
Flux Density	1.1	T
Magnet Material/Mass	Ceramic

Thiele-Small parameters
Resonance frequency	Fs	23.4	Hz
DC resistance	Re	6.5	ohm
Mechanical factor	Qms	14.4
Electrical factor	Qes	0.22
Total factor	Qts	0.22
Mechanical compliance	Cms	0.1	mm/N
Mechanical resistanceof suspension losses	Rms	4.94	mech-ohm
Effective Moving Mass	Mms	485	gr
Half-space efficiency	Eff	2.14	%
BL Factor	BL	45.9	T.m
Equivalent Cas air load	Vas	385	liters
Effective piston area	Sd	0.1698	m2
Max.linear excursion	Xmax	12	mm
Voice-coil inductance	LelK	6.24	mH

Mounting Information
Overall Diameter	556	mm
Bolt Circle Diameter	528	mm
Bolt Hole Diameter	6.5	mm
Baffle Cutout Diameter	493	mm
Overall Depth	220	mm
Net Weight           28.5Kg

L21/8613 LF subwoofer loud speaker