Rockford Fosgate RP9317, RP9316, RP9314 operation manual Ca L C U L At I N G Po R T Le N G T H

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The Harmonics graph illustrates the advantage of using the Aeroport over a conventional tube. The human ear can sense .1% distortion. A standard tube can reach that amount with only 10 watts of input where as the Aeroport reaches only .05% distortion with 50 Watts of input. The end result? You can apply more input power with less distortion or use a smaller diameter Aeroport in place of a standard tube.

If using a computer aided speaker design program such as Term-Pro, port velocities of up to 15% can be alleviated.

CA L C U L AT I N G PO R T LE N G T H

After the enclosure has been designed, the following formula may be useful when calculating the port length:

Lv =

8466.4R2

–1.463R

(Vb)Fb2

Lv = port length in inches

Vb = volume of box in cubic feet Fb = tuning frequency

R = radius of port

RP9314 RP9316

Radius

>Radius >

R=1.34 R=2.03

When cutting the Aeroport center tube, the length should be cut 3"

shorter than calculated. When the end flanges are affixed, each end extends the tube one and a half inches. If the determined port length is 10" then the fully assembled Aeroport (center tube with flanges attached) should measure 11" (the extra 1/2" on each end contributes to harmonics and not the length of the tube).

11" Overall Length

10"

Standard Tube

7" Cut Length

Aeroport Tube

2

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Contents R O P O R T Practice Safe Sound B L E O F C O N T E N T S OP E R AT I N G / FE AT U R E S Aeroport ContentsT R O D U C T I O N CA L C U L AT I N G PO R T LE N G T H MO U N T I N G TH E AE R O P O R T S TA L L AT I O N CO N S I D E R AT I O N SWA R R a N T Y in F O R M AT I O N Rockford Fosgate