Specifications
29
speakers
distributed
JBL Speakers Distributed – Ceiling Mount
Ceiling Mount
JBL Control 226C/T
When only the best will do. The ultimate 6.5” 2-way with
integrated back can & grille.
47Hz-19kHz •
150 watts program•
90dB (1W/1m)•
8 ohms•
120° conical •
226CT 70/100V taps: 60W, 30W, 15W, (7.5W 70v only)•
330 x 246mm (h x dia)•
JBL C300 12” Ceiling Speakers
Premium high-fidelity performance for no compromise systems.
JBL Control 227C/CT
When only the best will do. The ultimate 6.5” coaxial with
independent back can & grille.
43Hz-19kHz •
150 watts program•
90dB (1W/1m)•
8 ohms (227C)•
120° conical•
227CT 70/100V taps: 68W, 34W, 17W, (8.5W 70v only)•
305 x 147mm (h x dia)•
328C – 8” coax 2 way
45Hz-18kHz•
250 watts•
120° conical•
93dB (1w/1m)•
305 x 160mm (h x dia)•
Optional
MTC-300BB8 back box•
MTC-RG6/8 grille•
321C – 12” coax 2-way
34Hz-18kHz•
250 watts•
90° conical•
94dB (1w/1m)•
366 x 366mm square baffle•
223mm depth•
Optional
MTC-300BB12 back box•
MTC-300SG12 grille•
328CT – As above with
60W transformer•
60W, 30W, 15W, (7.5W 70v only)•
305 x 218mm (h x dia)•
321CT – As per 321C with
60W transformer•
68W, 34W, 17W, (8.5W 70v only)•
366 x 366mm square baffle•
240mm depth•
312CS – 12” in-ceiling subwoofer
30Hz-4.5kHz•
400 watts•
93dB (1w/1m)•
8 ohms•
366 x 366mm square baffle •
160mm depth
What is the difference between constant voltage system (70v/100v) and ‘normal’ system?
And why should I choose one over the other?
Constant voltage systems step up the nominal voltage on the speaker line to a higher voltage, either 70v or 100v, to reduce the effects of cable losses.
Constant voltage speakers present higher impedance to the line than ‘normal’ low impedance speakers. Higher impedance speakers draw less current
from the amplifier, and since cable loss is proportional to current, cable losses are greatly reduced.
For example, let’s consider two systems. System 1 is a traditional low impedance system. With 4 x 8 ohm loudspeakers connected to a 400w amplifier
via 100m of 1mm2 speaker cable.
Total speaker load = 8/4 = 2 ohms
Loss on speaker cable = 9dB
Power delivered to the speakers = 49w
Speaker cable loss = 87%
Wow, the majority of our amplifier power is being wasted heating up the speaker cable! Now let’s change to a constant voltage system feeding 4 x 100v
speakers tapped at 100w each.
Total speaker load = 100/4 = 25 ohms
Loss on speaker cable = 1.2dB
Power delivered to speakers = 303w
Speaker cable loss = 24%
You can see that the constant voltage system is far more efficient. In fact we would have to increase the speaker cable to 30mm2 in the first example to
even come close to the cable loss of the constant voltage system. That’s a BIG cable, we’re talking the stuff they use for welding cable!!!
TECH-TIPS