... cloth, new horn will be very rigid , it need to be soften, after doing this, the speaker will be durable and good ... than 5 °C,surrounds will be very fragile , if one use bigger voice, it will break the surrounds. If ... than 40 °C, voice coil will be hot, and the music will be bad. So avoiding to put the ... it, and when opening the speaker , there will be huge signal impact into it.Second condition : When ...