Harmonic Chorus(Complete Adventurer, p. 150)
Enchantment (Compulsion) [Mind-Affecting]
Level: Bard 3,
Components: V, S, AF,
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One living creature
Duration: Concentration, up to 1 round/level (D)
Saving Throw: Will negates (harmless)
Spell Resistance: Yes
Harmonic chorus lets you improve the spellcasting ability of another spellcaster. For the duration of the spell, the subject gains a +2 morale bonus to caster level and a +2 morale bonus on save DCs for all spells she casts.
Focus: A tuning fork.