Monitors sounding kinda flat

[VirtualSamana]

It may be my ears but my monitors (JBL lsr25ps) aren't sounding as sharp as they used to.

I foolishy left them over my friends house while mixing over there and he admitted to driving the bass hard enough for them to distort. If I can prove they were damaged my friend will have to cough up the moola to get them fixed and or replaced.

I was thinking a way of testing this would be to generate some test tones. Anyone know how to do this across the frequency spectrum? Is there a freeware program that can do this for me?

[loubeck]

There's this:
http://www.esser.u-net.com/ttg.htm

But it's kind of old and clunky.

I think the demo version of Wavelab has a great tone generator built into it as well.