Yes, Bose did put light bulbs in their speakers. As voltage levels increase, there is enough energy there to light up the bulbs. The bulbs can be lit full time if the energy level is of a high enough average or only light up momentarily on peaks if the music is basically low level with big dynamic swings. Obviously, the power transfer from amp to drivers is not very linear in this fashion, but i don't think that the manufacturer was really worried about this. The end result is reduced dynamic range i.e. "squashed" peaks AND less warranty claims from blown drivers.
For the record, i found this out when i was 13 years old with a pair of 301's. I was listening to some music at volume ( you would have never guessed, huh ??? ) with the grill's off and i saw something "flashing" out of the ports. I instantly thought that something was arcing or burning up in the speaker, so i ran over and turned the volume down. Being the technical geek that i am ( yes, even back then ), i took the speaker apart to see what was happening. Needless to say, that is when i discovered the light bulbs. I still have the crossovers from those 301's as a reminder of how "junk" can be foisted upon the mass market and made to look desirable. The good thing is, the light bulbs still work and i could use them in an emergency if i had to : ) Sean
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