OK- all the guess were very good,when Bose
first put out the model 101,people kept blowing the driver,so when they took it in under warranty,the repair pack came with a new speaker and what they called a "speaker limiter",the first 301/501's had the same problem-blown tweeters,so they would put a replacement tweeter,a fuse holder and speaker limiter in the repair pack,this one looked like a automotive light blub,if you have one of these models,take off the grill cover and look down the port,crank the volume up and you should see some light flashing.around my house when the kids were little I always owned vintage/highend equipment and had these things wired to my speakers,just in case the kids would play my sound system when I wasnt around,at first I had fuses wired in line but they blew to easy,these"speaker limiters"worked real good.I only have a few left,whats real funny is I made a call to "the mountain" a few years back and was told they had no idea of what I was talking about and if I had a problem with a product to take it to a repair center,I wish I had saved the flyier that came with the repair packs so I could have sent it to Bose
,I may be older but I havent lost my mind. anyway they really did this kind of stuff to fix their BOSE
junk,I will post the picture of the light blub type when I dig it up.