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Acoustic array of 40Hz

Acoustic array of 40Hz

Acoustic array of 40Hz

(OP)
Finally, I move from Antenna & Propagation to here. I have a project using more than 100 acoustic electromagnetic buzzer to get the strongest pressure at a 3m away target. Actually the buzzer is acoustic small at 40Hz, about 25mmX25mmX25mm in size. According to the requirement the array can not be so large, when I perform the calculation, I found the mutual coupling is so strong. And the active impedance vary from center to the outside with huge difference. And the active resistance is 20 times the isolated buzzer had at the edge. And the array is placed on the ground.
Dear friends, my questions are:
1. the rated voltage is 70~150V AC, can I use the sine wave to drive the array in paralell? or should I to transform the electricity to square wave in Vop?
2. If I provide enough current to stimulate the buzzer, the voltage may exceed the labeled operation voltage 110V AC(considering the 20 times resistance at the edge of the array),how can I deal with it?
3. Should I use a limiting resistor when the energy is supplied by wall plug?
4. If I still want to improve the sound pressure, do the plused helmholtz resonator and the waveguide horn really work in such low frequency at such near place?
5. If I use a sequential phased cubic array, can I improve the sound pressure more already having the ground relection superposition? How to get or design the time delay line?
I konw the questions are so many, Because I'm electromagnets not acoustic background. Thank you in advance!

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