Ideal Volume level

I've heard that preamps work best when the volume is set higher, and also that if you turn the volume past 12 o'clock you will destroy something...

This last comment seems to be too general, since the gain of the preamp will have a lot to do with this.

Here's why I am asking; most of the preamps I've owned had a gain of 20db, and the volume knob seldom reached the 10 o'clock position. Now I have a preamp with a gain of 11.5 db, and with some recordings I find myself listening at 12'oclock or a bit higher. Everything sound fine, no distortion at all, and the amp is far from clipping (I think). But, should I be concerned???

Here's the gear in case it helps:
Pre: Audio research SP16L with 11.5 db gain
Amp: Belles 350a ref with input sensitivity of 1.98V (500 WPC at 4 ohms)
Speakers: 4 ohms and 86DB
CDP puts out 0-2.2 V

Thanks for helping :)