Dayton Audio Reference RS180P-4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 86.2dB
• Frequency response 35 - 8000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 37.7Hz
• Mechanical quality factor QMS 1.98
• Electrical quality factor QES 0.48
• Total quality factor QTS 0.39

Large signal parameters

• Maximum linear excursion xmax 6mm
• Air volume displaced at xmax VD 76cm³
• Power handling P 60W
• Program power Pmax 90W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.1Ω
• Inductance (1kHz) LE 0.47mH
• VC Diameter 38.5mm

Magnet

• Force factor Bl 4.67N/A
• Motor constant Bl/√RE 2.65N/√W
• Material Ferrite

Diaphragm

• Effective diameter 127mm
• Effective area SD 127cm²
• Moving mass MMS 14.8g
• Moving mass (without air load) MMD 13.7g
• Material Paper / Kevlar

Suspensions

• Stiffness KMS 0.826N/mm
• Compliance CMS 1210µm/N
• Equivalent volume to the compliance VAS 27.3L
• Mechanical resistance RMS 1.77N·s/m
• Surround material Rubber

Dimensions

• Nominal diameter 7″
• 181mm
• Overall diameter 181mm
• Baffle cutout diameter 146mm
• Overall depth 81mm
• Volume occupied by the driver (estimated) 0.55L
• Frame material Cast Aluminium