Boundary Microphone

Shure WL690 L4 Microflex Wireless Boundary Microphone Perfect Condition
Shure WL690 L4 Microflex Wireless Boundary Microphone Perfect Condition
Paypal   US $149.00
Lot of 3 Shure MX692 C UA Wireless Boundary Microphone
Lot of 3 Shure MX692 C UA Wireless Boundary Microphone
Paypal   US $200.00
Shure MX690 L4 Microflex Wireless Boundary Microphone
Shure MX690 L4 Microflex Wireless Boundary Microphone
Paypal   US $200.00
Shure MX690 H5 Microflex Wireless Boundary Microphone
Shure MX690 H5 Microflex Wireless Boundary Microphone
Paypal   US $200.00
Shure MX690 Boundary Microphone Cardioid Wireless H5
Shure MX690 Boundary Microphone Cardioid Wireless H5
Paypal   US $451.07
Shure MX690 Boundary Microphone Cardioid Wireless G5
Shure MX690 Boundary Microphone Cardioid Wireless G5
Paypal   US $451.07
Shure MX690 Microflex Wireless Boundary Mic Ch J3
Shure MX690 Microflex Wireless Boundary Mic Ch J3
Paypal   US $499.99
Shure MX690 Microflex Wireless Boundary Mic Ch Q4
Shure MX690 Microflex Wireless Boundary Mic Ch Q4
Paypal   US $499.99
Shure MX690 L4 band  Table top Wireless Boundary Microphone
Shure MX690 L4 band Table top Wireless Boundary Microphone
Paypal   US $345.00
Shure Microflex MX391BP C Boundary Microphone
Shure Microflex MX391BP C Boundary Microphone
Paypal   US $110.00
Shure MX692 C UA wireless boundary microphone mic
Shure MX692 C UA wireless boundary microphone mic
Paypal   US $69.00
Shure MX690 Microflex Wireless Boundary Mic CH G4
Shure MX690 Microflex Wireless Boundary Mic CH G4
Paypal   US $499.99

Using Shure Boundary Mics with a Canon HV 30

Calculus, help is very much appreciated!?

When recording live performances, sound engineers often use a microphone with a cardioid pickup pattern because it suppresses noise from the audience. Suppose the microphone is placed 4 m from the front of the stage and the boundary of the optimal pickup region is given by the cardioid r = 8 + 8sin(theta), where r is measured in meters and the microphone is at the pole. The musicians want to know the area they will have on stage within the optimal pickup range of the microphone. Answer their question.

Any help is very much appreciated!

If you have a function r = f(θ), then the area between the origin and the curve between a <= θ <= b is
(1/2) ∫( f(θ) )^2 dθ, integrated from a to b

So you just have to integrate this:
(1/2) ∫(8 + 8sin(θ) )^2 dθ
(1/2) ∫ 64(1 + sin(θ) )^2 dθ
32 ∫ (1 + sin(θ) )^2 dθ
32 ∫ 1 + 2sin(θ) + sin^2(θ) dθ

Since cos(2x) = cos^2(x) - sin^2(x) = 1 - 2sin^2(x), then sin^2(θ) = (cos(2θ) - 1)/2

32 ∫ 1 + 2sin(θ) + (cos(2θ) - 1)/2 dθ
32 [ θ - 2cos(θ) + (1/4)sin(2θ) - (1/2)θ ]
Try the full range of 0 <= θ <= 2pi

Nice question. I do a podcast and I was fiddling around with microphone settings just last night. I've worked with cardioid mics before, but never thought of applying polar equations to it.