Hertz Cento C 165

• Sensitivity (1W, 1m, infinite baffle) SPL1W 87.7dB
• Frequency response 55 - 7000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 60Hz
• Mechanical quality factor QMS 3.90
• Electrical quality factor QES 0.69
• Total quality factor QTS 0.59

Large signal parameters

• Maximum linear excursion xmax 3.5mm
• Maximum excursion before damage xlim 4.9mm
• Air volume displaced at xmax VD 47cm³
• Power handling P 70W
• Program power Pmax 210W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.2Ω
• Inductance (1kHz) LE 0.2mH
• VC Diameter 25mm

Magnet

• Force factor Bl 4.9N/A
• Motor constant Bl/√RE 2.74N/√W
• Diameter 85mm
• Height 15mm
• Material Ferrite

Diaphragm

• Effective diameter 132mm
• Effective area SD 135cm²
• Moving mass MMS 13.9g
• Moving mass (without air load) MMD 12.7g
• Material Semi-pressed paper+ Mica

Suspensions

• Stiffness KMS 1.96N/mm
• Compliance CMS 510µm/N
• Equivalent volume to the compliance VAS 13.2L
• Mechanical resistance RMS 1.34N·s/m

Dimensions

• Nominal diameter 6.5″
• 165mm
• Overall diameter 165mm
• Baffle cutout diameter 142mm
• Overall depth 71mm
• Flange thickness 8mm
• Mounting depth 63mm
• Volume occupied by the driver (estimated) 0.35L
• Net weight 0.96kg