Irrational ratios/enclosure dimensions

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Ron E

Ron E

Member
Joined 2002
The square root of 2 is ~1.414, not 1.141.

Usual quoted enclosure ratios are based on:
phi = golden ratio = 1.6180339887499 why do I remember this number to so many decimal places? ;)
1.2
1.25

IMO, none of these is better than any other or any number you could come up with. It makes a lot more difference how you mount your drivers on the baffle (for diffraction) than what the box dimension ratios are. Lining or stuffing in the box is used to damp out the resonances.....

Your app calculates axial resonances, but there are also tangential and oblique resonances, and all are excited differently depending on where you mount the drivers...
 
C

Curmudgeon

Member
Joined 2005
Tapered boxes are good too; but these ratios are certainly better than integers, 1/2/2 for example. AND you should also line &/or stuff. Nothin' wrong with belt and braces. And positiong drivers non-equidistant from box edges, (which should have radii > 4 inches) also helps.

But one thing at a time, this is a nifty little calculator.
 
Cloth Ears

Cloth Ears

Member
Joined 2001
Ron E said:
Usual quoted enclosure ratios are based on:
phi = golden ratio = 1.6180339887499 why do I remember this number to so many decimal places? ;)
1.2
1.25

IMO, none of these is better than any other or any number you could come up with...
Click to expand...
Ron,

Agreed. But I tend to use the square root of phi (c. 1.27202) for the front of my woofer and subwoofer boxes as it looks better, rather than for any sound reasons. That way the ratio W/H is 1.618/1 (and when you're looking at it from a standing position, perspective also fools you into thinking it's the same ratio W/D).

Internal standing waves I try to damp out (or confuse) by:
1) damping materials;
2) internal bracing with small (eg 2" or 3") holes in it;
3) internal bracing at odd angles and shapes (eg. dowels of different sizes, braces at 15, 22.5, 30 and 45 degrees).

UNLESS I'm doing a TL...

But, Vikash, I think you've got 1.28 in your calculator anyway - and that's close enough to 1.27202
 
Geek

Geek

Member
Joined 2004
Vikash said:
I use perl ;)
Click to expand...

print "There can be only one\n";

:cool:

If there was an equivelant of php/GD for perl then that would work. I'll have to rummage through cpan again. Couldn't see anything obvious last time...
Click to expand...

There is. If you look through Freshmeat for perl-based image galleries, it'll list the equivalent module. I forget what it is, but that's how I found it ;)
 
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