cabinet ratio

[palesha]

Dear friends
I made my subwoofer tuned port cabinet with .6:1:1.6 golden ratio. I got excellent results. I saw many commercially made port tuned sub cabinets with .83:1:1.2 ratio. I will like to have comments & views about the different ratios which can be used in tuned port cabinet design.
Mahendra Palesha

 

[Dave Bullet]

Cabinet dimensions for subwoofer

I don't believe cabinet dimensions matter much for a subwoofer. The golden ratio and other ratios are designed for higher frequencies where the wavelength of higher frequencies can be smaller hence particular frequencies a box dimension might cause standing waves for multiples of that frequency's wavelength.

Since subwoofer frequencies are low - therefore wavelengths are long - standing waves aren't a problem in a subwoofer cabinet - the wavelengths for all frequencies are longer than any given dimension of a subwoofer.

Standing waves can be a problem however in room dimensions - hence the much more noticeable excitement of a particular bass frequency in particular rooms (in that case the golden ratio would be good to use in room dimension design - and adequate bracing )

Dave.

 

[palesha]

Dear Dave,
Thanks for the information.
MP

 

[palesha]

I want to make two kind of speaker boxes for computer. In one system i want to use 3" full range and ported box. In other system 4" woofer and dome tweeter with ported box to be used. For cabinet design golden ratio applicable or not? I wish to use sound absorbing material in it.
Mahendra Palesha

 

[AudioFreak]

yeah in this case the golden ratio's are worth using if you have the space.

 

[Super]

I'd agree, if its a true subwoofer, then I wouldnt worry about it.

But if its a long throw 4 inch driver, which is likely to be crossed over very high, I would use the ratios.