Acoustic Graphs

Shape A- Sphere	Shape B- Sphere, squished	Shape C- Cylinder, center-mount	These graphs are from experiments performed in 1950 at RCA's research labs
			at Princeton. The driver used was a sealed-back unit. What this means is that the responses you see here are effected only by *the outer shape of the enclosure!* Notice how Shape C, the cylinder, generates a
~~~~~~~~~~~~~~~~	~~~~~~~~~~~~~~~~	~~~~~~~~~~~~~~~~	strong "ringing" or resonance pattern.
Shape D- Cylinder, side-mount	Shape E- Cube, center-mount	Shape F- Cone, center-mount	One would suspect this, for the *interior*, given the cylindrical nature of ports,
			but it is interesting to see that the *exterior* effect applies as well. Also look at the response from Shape E, the cube - same high-resonance pattern. Not very desirable!
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Shape G- Dual cone	Shape H- Pyramid	Shape I- Dual Pyramid
			Here are some more shapes. No strong resonance patterns but exterior effects are clearly in evidence!
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Shape J- tweaked cube	Shape K- Rectangular	Shape L- Tweaked rectangular
			Here are what most designers settle for, some twiddling in the front baffle and driver placement. Helps a little but you can still see the bumps and dips. Even computerized tweaking cannot deliver the strong, smooth, natural response that our spherical, ovoid, or wing-shaped enclosures do. The tweakers are fighting against physics.

	Here we have another form of exterior diffractions, the results from sound bouncing off objects, in this case a cylinder. These experiments were performed even earlier, in the 1930's. As you would suspect, the cylinder shows some of the same strong resonance patterns as we saw above.
	Here we see the acoustic reflections from a cube. Just as bad as the cylinder, even worse at some angles. Interior designers and decorators take note- please avoid placing any sharp-angled objects near the speakers!
	And here we have the sphere. Notice how it actually has a smoothing effect, in fact spheres have been hung in the Hollywood Bowl (see below) as acoustic correction devices. Talk about room treatment!