Peerless by Tymphany BC25TG15-08 Silk Dome Tweeter 8ohms This BC family tweeter features a 8 ohm 25 mm voice coil, a damped fabric dome for smooth frequency response performance, and ferrofluid in the gap of the ferrite motor, providing enhanced cooling of the voice coil. The tweeter comes with a compact faceplate with recessed mounting holes, complete with sealing gasket which helps in reducing vibration between baffle and driver.DescriptionDriver Size- 1 InchDC Resistance- 6.53 ΩResonant Frequency- 1136.9 HzHalf Space Sensitivity @ 2.83V- 91.71 dBSensitivity @ 1W/1m- 91.3 dBRated Noise Power (IEC 268-5 18.1)-100 WTest Spectrum Bandwidth- 1KHz-20KHz 12 dB/OctEffective Piston Area- 6.2 cm2Moving Mass- 0.4 gMotor Force Factor- 3.24 TmVoice Coil Inner Diameter- 25.4 mmGap Height= 3 mmMaximum Linear Excursion- 0.5 mmFerrofluid Type- APG027NMinimum Impedance- 7.27 ΩVoice Coil Inductance- 0.04 mHMechanical Q Factor- 2.21Electrical Q Factor- 1.58Total Q Factor- 0.92Ratio- 1233.08 fs/QtsEnergy Bandwidth Product ((1/Qes)fs)- 720.15Suspension Compliance- 55 μm/NEffective Cone Diameter- 2.8 cmMotor Efficiency Factor- 1.6 (Tm2)/ΩVoice Coil Former Material- ASVDriver Mass- 0.52 KgEquivalent Volume- 0 LSpecificationDriver Type: TweeterSize: 1 InchMotor: FerriteFrame: Plastic FaceplateImpedance: 8 ΩDiaphragm: Fabric