Jamo D 7 SUB Owner/User Manual - Page 17

D 7LCR / D 7SUR / D 7SUB description D 7LCR D 7LCR is a 3-way speaker with two 5½"woofers, two 2½" midrange drivers and one 1" tweeter, see more details about the driver units below. The compact drivers improves the dynamics: As they weigh less they can move faster. Of course under the precondition that they are equipped with very powerful motors (magnet/voice coil) as is the case here. The two midrange drivers are placed vertically over / under the tweeter and the woofers are placed on each side of the midrange/tweeter array. The crossover frequencies are 400 Hz and 2k Hz. There are several advantages of these low crossover frequencies when you, as in this case, have the drivers to match them. Every diaphragm has a break up point and it is important that the driver is used in a range where break ups are controllable or do not appear. Of course the further away from the break up point the better. In D 7LCR the crossover frequency for the woofers is 400Hz and the diaphragm's break up point occurs above 2k Hz. Therefore using a 2'nd order crossover is fully applicable and phase errors that often occur with higher order crossovers are avoided. The two woofers in the D 7LCR are mounted horizontal beside each other which at higher frequencies (over 2k 7