Pride ST 18

• Sensitivity (1W, 1m, infinite baffle) SPL1W 90.5dB

Thiele & Small parameters

• Resonance frequency (free air) fS 22.1Hz
• Mechanical quality factor QMS 4.67
• Electrical quality factor QES 0.25
• Total quality factor QTS 0.24

Large signal parameters

• Maximum linear excursion xmax 37.5mm
• Air volume displaced at xmax VD 4950cm³
• Power handling P 5000W
• Program power Pmax 10000W

Voice Coil

• Nominal impedance Z 1Ω
• DC resistance RE 0.9Ω
• Inductance (1kHz, estimated) LE 1.55mH

Magnet

• Force factor Bl 18.5N/A
• Motor constant Bl/√RE 19.5N/√W

Diaphragm

• Effective diameter 410mm
• Effective area SD 1320cm²
• Moving mass MMS 692g
• Moving mass (without air load) MMD 660g

Suspensions

• Stiffness KMS 13.3N/mm
• Compliance CMS 75µm/N
• Equivalent volume to the compliance VAS 185L
• Mechanical resistance RMS 20.6N·s/m

Dimensions

• Nominal diameter 18″
• 457mm
• Volume occupied by the driver (estimated) 6.9L