Dayton Audio Reference RS180-4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 84.7dB
• Frequency response 39 - 3600Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 38.4Hz
• Mechanical quality factor QMS 2.13
• Electrical quality factor QES 0.59
• Total quality factor QTS 0.46

Large signal parameters

• Maximum linear excursion xmax 6mm
• Air volume displaced at xmax VD 75cm³
• Power handling P 60W
• Program power Pmax 120W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.1Ω
• Inductance (1kHz) LE 0.45mH
• VC Diameter 38mm
• Winding material Copper
• Former material Aluminum

Magnet

• Force factor Bl 4.71N/A
• Motor constant Bl/√RE 2.68N/√W
• Material Ferrite

Diaphragm

• Effective diameter 126mm
• Effective area SD 125cm²
• Moving mass MMS 17.8g
• Moving mass (without air load) MMD 16.7g
• Material Black Anodized Aluminum

Suspensions

• Stiffness KMS 1.03N/mm
• Compliance CMS 970µm/N
• Equivalent volume to the compliance VAS 21.2L
• Mechanical resistance RMS 2.02N·s/m
• Surround material Rubber

Dimensions

• Nominal diameter 7″
• 181mm
• Overall diameter 181mm
• Baffle cutout diameter 146mm
• Overall depth 82mm
• Volume occupied by the driver (estimated) 0.55L
• Frame material Cast Aluminium