Alphasonik PTZ25SE, PTZ20TE, PTZ25TE owner manual 23-1.5=21.5

Step Two

Calculating speaker enclosure volume is a five step procedure.

(Make sure you do not forget to subtract the thickness of the wood and port displacement that you used.)

Step One: Measure Height

Step Two: Measure Width

Step Three: Measure Depth

Step Four: Height x Width x Depth

Step Five: Divide the results in step four by 1728 (12" x 12" x 12"=1728 which equals to 1.0 cu ft.) Complete formula should look like this

Height x Width x Depth / 1728 =__________

Below are illustrated versions of all the steps that you should take.

(FOR EXAMPLE ONLY)

						4"					23-1.5=21.5
							12"			13.5"
					4.5"
Step One								21.5"
							23"
									The wood that we are using is 0.75" thick
									The 1.5 that you see in the formula is the thickness
	Step Three								of the wood.
									To calculate the thickness of the wood.
		Side View
									Left + Right=1.5
									Top + Bottom=1.5
									Front + Back=1.5
		7"
									.75 x 2=1.50
			13.5"						21.5 x 13.5 x 12=3483
									3483 / 1728=2.01
									2.01 cu. ft. is the result for this enclosure.
				15"
15-1.5=13.5									Formula to calculate port displacement
									3.14 x Radius x Radius x Depth=
									________ / 1728=port displacement
									3.14 x 2.25 x 2.25 x7=111.27 sq. in.
									111.27 / 1728=.06 is the displacement of the port
									2.01 - 0.06=1.95 cu.ft. is the final result for this
	Patent No: US D478,556 S								enclosure.
	Patent No: US 6,601,645 B1

Patent No: US 6,656,000 B2

B U I L D I N G A N E N C L O S U R E

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