Hertz Mille MP 250 D4.3 PRO

• Sensitivity (1W, 1m, infinite baffle) SPL1W 83dB

Thiele & Small parameters

• Resonance frequency (free air) fS 27Hz
• Mechanical quality factor QMS 5.80
• Electrical quality factor QES 0.53
• Total quality factor QTS 0.50

Large signal parameters

• Maximum linear excursion xmax 17mm
• Maximum excursion before damage xlim 27mm
• Air volume displaced at xmax VD 593cm³
• Power handling P 600W
• Program power Pmax 1200W

Voice Coil

• Nominal impedance Z 2 x 4Ω
• DC resistance (in series) RE 7.2Ω
• Inductance (1kHz, in series) LE 6.4mH
• VC Diameter 65mm

Magnet

• Force factor (in series) Bl 21N/A
• Motor constant Bl/√RE 7.83N/√W
• Diameter 156mm
• Height 35mm
• Material Ferrite

Diaphragm

• Effective diameter 213mm
• Effective area SD 349cm²
• Moving mass MMS 187g
• Moving mass (without air load) MMD 182g
• Material Pressed-pulp cone with mineral powders

Suspensions

• Stiffness KMS 5.56N/mm
• Compliance CMS 180µm/N
• Equivalent volume to the compliance VAS 31L
• Mechanical resistance RMS 5.47N·s/m

Dimensions

• Nominal diameter 10″
• 250mm
• Overall diameter 268mm
• Baffle cutout diameter 236mm
• Overall depth 160mm
• Flange thickness 19mm
• Mounting depth 141mm
• Volume occupied by the driver (estimated) 3.1L
• Net weight 7.8kg