PA Services
-large system
-small system
-musician info

12v PA info
-bike generators
-power control & batts
-gtr & bass amplifiers
-misc kit

domestic 12v info

lower voltages
-6v systems
-USB/phone power
-wind-up devices



[big speakers pic]

(big speaker construction info)

[small speaker pic]

The small speakers are home constructed from 12mm ply (front & back) and 18mm (other sides). Parts - 14x12x6" boxes, painted in blackboard paint. Main drivers - Monacor SP-202E ( their code 10.3980) 8" dia 50W rms 4 Ohm - SPL 91dB. A compromise on size, price & efficiency - in these applications speaker efficiency, which can vary greatly, as does the useful audio volume. Tweeters - cheap piezo horns, wired in with a series 80 Ohm resistor.