On February 3, 2018 at 17:13, buzz said...
In some respects you are asking for us to help you specify a car that is "totaly safe". The reality is that the operator is responsible for safe operation.
If the sound is clean, you will probably not damage the speaker.
kgossen said as much, and it's true.
It's possible to have a line level signal that is large enough that an amplifier, turned all the way up, can distort. The simplest type of distortion caused this way is that a sine wave turns into something resembling a square wave.
A sine wave is a sound of only one frequency. A square wave has the same basic tone, but a horrendous amount of high frequency overtones are added by the way the signal is distorted. This will be WAY MORE such high frequency power than music ever contains.
Thus, while a speaker may play okay with 60 clean watts of power, 10 watts of horribly distorted power may blow it. And you'd expect the woofer to blow, because that's where most of the power usually goes... but remember that this kind of distortion has a lot of high frequency energy, so tweeters will blow!
There's a lot to it. Learn to recognize distortion, and avoid it. That's a really good rule for pretty much all of audio.