Precision Devices PD.18BR40

• Sensitivity (1W, 1m, infinite baffle) SPL1W 95.5dB
• Frequency response 35 - 3000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 30Hz
• Mechanical quality factor QMS 10.21
• Electrical quality factor QES 0.33
• Total quality factor QTS 0.32

Large signal parameters

• Maximum linear excursion xmax 10.5mm
• Air volume displaced at xmax VD 1191cm³
• Power handling P 700W
• Program power Pmax 1400W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.1Ω
• Inductance (1kHz) LE 1.03mH
• VC Diameter 101mm
• Winding height HVC 25mm
• Winding material Copper
• Former material Glass Fibre

Magnet

• Flux density B 1.34T
• Force factor Bl 22N/A
• Motor constant Bl/√RE 9.75N/√W
• Air gap height HAG 9mm
• Material Ceramic

Diaphragm

• Effective diameter 380mm
• Effective area SD 1134cm²
• Moving mass MMS 164g
• Moving mass (without air load) MMD 136g
• Material Paper

Suspensions

• Stiffness KMS 5.85N/mm
• Compliance CMS 171µm/N
• Equivalent volume to the compliance VAS 309L
• Mechanical resistance RMS 3.03N·s/m

Dimensions

• Nominal diameter 18″
• 460mm
• Overall diameter 474mm
• Baffle cutout diameter 415mm
• Overall depth 188mm
• Flange thickness 13mm
• Mounting depth 175mm
• Volume occupied by the driver (estimated) 7.2L
• Net weight 14.2kg