To add even more that is just with an amp with a regulated power supply if it's unregulated then you will increase power. If your going for spl, otherwise not really worth the effort and as mentioned a higher than normal voltage causes other problems.

meant in general terms..you can`t have one without the other.

No. Your initial post was just wrong. Adding "in general" doesnt make sense or make it right. ha :p

And this post is also wrong, you can indeed have voltage without current. But not the other way around.

;) :p