Hi,
I don't have a piezoelectric buzzer with me, so I cannot try it but, is there any reason why it would not sound louder when using B instead of A?
A) Excitation = 2 kHz, square wave with +3.3 V, 0 V levels. B) Excitation = 2 kHz, square wave with +3.3 V, -3.3 V levels.
I think B should sound louder (power should be four times higher).
Are these devices deformed (bent) into the negative direction when a negative voltage is applied? Is there any mechanical limitation concerning negative excitations?
Thank you.