The Eminence Deltalite II 2510 is recommended for professional audio as a mid, high, or full-range and monitor speaker; or for bass guitar amps, the Deltalite II 2510 is a 10" neodymium speaker with a power rating of 250W and a peak of 500W. The PA speaker features an aluminum voice coil, paper cone, die-cast aluminum basket/heatsink, and works well in sealed or vented enclosures.Specs: Nominal basket diameter: 10", 254mm Nominal impedance: 8 ohms Power rating: 250W Peak: 500W Resonance: 53Hz Usable frequency range:: 60Hz-4kHz Sensitivity: 97.3 Magnet weight: 7 oz. Gap height: 0.275", 7mm Voice coil diameter: 2.5", 63.5mm Thiele & Small Parameters Resonant frequency (fs): 53Hz DC resistance (Re): 5.06 Coil inductance (Le): 0.40mH Mechanical Q (Qms): 5.76 Electromagnetic Q (Qes): 0.45 Total Q (Qts): 0.42 Compliance equivalent volume (Vas): 52.5 liters / 1.9 cu.ft. Peak diaphragm displacement volume (Vd): 147cc Mechanical compliance of suspension (Cms): 0.30mm/N BL product (BL): 10.6 T-M Diaphram mass inc. airload (Mms): 31g Efficiency bandwidth product (EBP): 117 Maximum linear excursion (Xmax): 4.2mm Surface area of cone (Sd): 350.1 cm2 Maximum Mechanical Limit: (Xlim) 8.0mm Mounting Information: Sealed: 12.7-17 liters/0.45-0.6 cu.ft. Vented: 17.39.6 liters/0.6-1.4 cu.ft. Overall diameter: 10.25", 260.4mm Baffle hole diameter: 9.15", 232.4mm Front sealing gasket: fitted as standard Rear sealing gasket: fitted as standard Mounting holes diameter: 0.28", 7mm Mounting holes B.C. D.: 9.73", 247.1mm Depth: 4.9", 123.8mm Net Weight: 4.6lb., 2.1kg Materials of Construction Coil construction: Aluminum voice coil Coil former: Polymide former Magnet composition: Neodynium magnet Core details: Vented core Basket materials: Die-cast aluminum basket/heatsink Cone composition: Paper Cone Cone edge composition: Cloth cone edge Dustcap composition: Solid composition paper dust cap