Brand NEW! Including 90 Days USA Factory Warranty. The Dayton Audio ND91-8 3-1/2" Neo-Balanced full-range driver balances low distortion, extended range, and surprising bass impact. Its sophisticated motor design provides the underhung 1" voice coil with extended linear travel within the magnetic field. When teamed up with the matching ND series passive radiators this driver can produce incredible full sound from compact enclosures. Key Features Low distortion, full-range 65 Hz to 17 kHz performance Rubber-edged black anodized aluminum alloy cone Large excursion capability?5.1 mm Xmax, 25 mm peak Self-shielded Neo-Balanced motor structure with copper alloy shorting ring 1" 4-layer underhung voice coil with polyimide former 30 watts RMS power handling Great for line arrays and micro monitors Dayton Audio's ND91 aluminum cone full-range drivers are the latest addition to the acclaimed ND Series high output/low distortion neodymium transducers. By increasing the original ND90's voice coil diameter from 3/4" to 1" and adding a copper alloy shorting ring, the ND91-8 features even lower distortion and delivers better bass impact and dynamic range?with peak Xmax up to 25 mm! This high-BL version further exploits the low distortion characteristics of the Neo-Balanced motor's optimized magnetic field, making the ND91 drivers an excellent choice for full-range point-source speaker enclosures, as well as extremely accurate, high resolution line arrays. Product Specifications Nominal Diameter 3-1/2" Bolt Circle Diameter 3.66 Moving Mass Of Diaphragm (Mmd) 4.8 Power Handling (RMS) 30 Watts Power Handling (MAX) 60 Watts Impedance 8? Frequency Response 70 to 17,000Hz Sensitivity 82.1dB 2.83V/1m Voice Coil Diameter 1" Thiele-Small Parameters Resonant Frequency (Fs) 70.7Hz DC Resistance (Re) 7.8? Voice Coil Inductance (Le) 1.24mH Mechanical Q (Qms) 4.29 Electromagnetic Q (Qes) 0.53 Total Q (Qts) 0.47 Compliance Equivalent Volume (Vas) 0.05ft Mechanical Compliance of Suspension (Cms) 1.05mm/N BL Product (BL) 5.63T·m Maximum Linear Excursion (Xmax) 5.1mm Surface Area of Cone (Sd) 30.4cm Materials of Construction Cone Material Aluminum Surround Material Rubber Voice Coil Wire Material Aluminum Voice Coil Former Kapton / Polyimide Basket / Frame Material Steel Magnet Material Neodymium Mounting Information Overall Outside Diameter 3.35" Baffle Cutout Diameter 3.01" Depth 2.22" # Mounting Holes 4 Optimum Cabinet Size (determined using BassBox 6 Pro High Fidelity suggestion) Sealed Volume 0.02ft Sealed F3 139Hz Vented Volume 0.04ft Vented F3 75Hz - All international buyers are responsible for all tax, duties and/or customs fees.