Celestion TF0615MR - 6" Mid-Range Speaker - 8 Ohm. This compact model has been optimised to deliver detailed reproduction of the mid range part of the audio spectrum. Suitable for use in 3-way systems, the 0615 MR gives a smooth response through the vocal range. Its closed back chassis simplifies cabinet manufacture that eliminates the need for a separate mid range enclosure. General specifications Nominal diameter (mm/in) 152/6 Power Rating (AES, W rms) 50 Nominal impedance (?) 8 Voice coil diameter (mm/in) 38/1.5 Magnet type Ceramic Magnet weight (kg/oz) 0.48/17 Chassis type Pressed steel Sensitivity (dB) 97 Frequency range (Hz) 50-5000 Coil material Round copper Former material Round copper Cone material Kevlar loaded paper Surround material Cloth-sealed Suspension Single Xmax (mm/in) n/a Gap depth (mm/in) n/a Voice coil winding width (mm/in) n/a Small Signal Parameters Sd (m2/in2) n/a D (m/in) n/a Fs (Hz) n/a Mmt (g/oz) n/a Mmd (g/oz) n/a Qms n/a Qes n/a Qts n/a Re (?) 5.70 Vas (lt/ft3) n/a BI (Tm) n/a Cms (mm/N) n/a Rms (kg/s) n/a Mounting Information Overall diameter (mm/in) 178/7.01 Overall depth (mm/in) 74/2.91 Cut-out diameter (mm/in) 147/5.79 Mounting slot dimensions (mm/in) Ø 4.3/0.17 Number of mounting slots 4 Mounting slot PCD range (mm/in) 168.5/6.63 Unit weight (kg/lb) 1.4/3.1 Packed Dimensions and Weight: Single pack size W x D x H (mm/in) 190 x 200 x 90/7.5 x 7.9 x 3.5 Single Pack Weight: 2kg/4.4lbs. Multipack (140) size W x D x H (mm/in) 1070 x 850 x 860/42.1 x 33.5 x 33.9 Multipack (140) Weight: 295kg/650lbs.