Speaker size dictates the lowest frequency sustaining a given coverage angle

Evidence

It is sometimes useful to be able to calculate the minimum frequency a speaker of a given size can achieve at a particular coverage angle. We can do this by rearranging equation A6.7: APPENDIX 6: Effect of Surface Size and Illumination 498 min sin sin sin 2 2 2 4 4 2 6 6 6 θ θ θ − Which, if we combine all the constants, becomes Equation A6. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2941