Questions about speaker overload protection (?) on Lepai LP-2020
I have just started rebuilding a couple of old JVC stereo speakers to a small beach stereo. I'm pretty much a noob when it comes to diyaudio, but I had a Lepai LP-2020 laying around so I hooked it up to the speakers and it sounded okey. Inside each speaker there is a speaker element rated to 4 Ohm and 8W power handling. If I ought to continue with my beach stereo project I would like to find a way to guarantee that some stupid friend of mine don't overload the speakers the first thing they do when I'm done. I have a similiar element (also rated 4 ohm and 8W power handling) that I have done some testing on and I have noticed that when I'm turning up the volume and the speakers starting to sound pushed the amp says "click" and stop playing. Is this some kind of inbuilt overload protection that would protect the speaker elements from blowing up? And could I count on it to protect my speaker elements in my beach stereo? It should be mentioned that during the testing I used a 12V 2A power supply and in my beach stereo I'm planing on using two 6V MC-batteries in serie.
If the inbuilt speaker overload protection (?) doesn't help me, what is the easiest way to protect the elements? I have thought about connecting a resistor in series to the speakers, but that sound like a waist of energy. I have also thought about making a mechanical stop on the volume control, that would guarantee a lower power-output and a lower distorsion on "max-volume" but it seems rather amateurish.
Thanks for all replies in advance, and sorry for the long text and bad language. Wanted to make myself as clear as possible and the bad language is just a effect of my tiredness. Hope you understand!