Bell Magic [General]
You employ the power of carefully crafted bells with your magic, strengthening them.
Prerequisite: Craft (bellmaking) 4 ranks, Perform (percussion) 2 ranks, Spellcraft 4 ranks
Benefit: If you use a masterwork bell as an additional focus to a spell when you cast it, the spell gains the sonic descriptor. This does not actually change the nature of the spell you cast; a fireball cast with this feat still deals fire damage, but since it also carries the sonic descriptor, it can be augmented by a number of feats which affect only spells with the sonic descriptor.
If you add the use of a masterwork bell as an additional focus to a spell when you cast it and that spell already has the sonic descriptor, you increase the effective level of the spell being cast by +1.
Adding this additional focus requires you to be holding the bell or able to employ the bell, and you must ring it during the casting of the spell. Thus, it cannot be employed when in the area of a silence spell.
The bell used must be of masterwork quality. Additionally, higher level spells demand bells of finer quality. The bell must be worth at least 100gp per spell level to function with a spell of that level.