Originally Posted by Seadaddy
I just found out why the bps 100 was not working, when mirage assembled the sub they never put a fuse in it. So that was an easy 75 cent fix. Also anyone know why they use a slow blow fuse? The only thing i can think of is that it will keep from blowing the fuse in the event of clipping.
Though all active (powered) equipment (amplifier, line-level source, processor, powered speaker such as sub-woofer with built-in amp, etc) has - or should have - fuses, passive loudspeakers generally do not have fuses.
According to most manufacturers and pro-sound sources, fuses aren't appropriate for loudspeakers. For example:
....fuses can add distortion as their impedance changes with heating, and are not the best match to model long term heating, or short term over excursion. http://www.gearslutz.com/board/geeks...rotection.html
....a fuse may blow with a signal that would not
damage the speaker, but it can also pass
that can damage
the speaker. http://www.jblpro.com/pages/general_faq.htm
Several manufacturers have used protection techniques such as light-bulbs which avoid some issues that fuses would create. Nonetheless, bulbs are not without their own foilables...for a detailed description see the New Zealaander's comments: http://www.churchsoundcheck.com/faq4.html
There's lots of other enlightening info about all this on the internet. For example, a higher-powered amplifier with undistorted un-clipped power is much preferred to a lower power amp which, when it distorts, can send nasty ugly clipped signals to the drivers and burn out the voice coils. An axiom is that speakers are more likely to be damaged by not having enough power than by having too much power. Without having sophisticated active processing such as a limiting curcuit, matching amplifier power to speaker efficiency, room size and acoustics, and listening-level requirements is the preferred method of loudspeaker protection.