how much does the shape of a cabinet matter???

[mlwarriner]

just thinking out loud here...

 

given a bass cabinet with a certain volume (cubic space, not decibel level), would a different cabinet with a similar volume but different dimensions sound similar?

 

discuss, please...

[Subsonicbass]

 

Originally posted by mlwarriner given a bass cabinet with a certain volume (cubic space, not decibel level), would a different cabinet with a similar volume but different dimensions sound similar?

 

 

 

 

 

No.

[Emprov]

Many high end home audio speakers are shaped in a way that there will be no two parallel surfaces inside the enclosure. There's a ton of high end happening on those though. Not sure how noticeable it'd be on a bass cab where you have mostly low end coming out. Interesting topic though, I'd love to hear some experiments or something.

[takeout]

If you've treated the cab so as to reduce or eliminate standing waves in 90 degree corners, it shouldn't matter. Cubic inches are cubic inches.

[mlwarriner]

Originally posted by takeout If you've treated the cab so as to reduce or eliminate standing waves in 90 degree corners, it shouldn't matter.

 

suppose you could elaborate? preferably in smaller words...

[Rowka]

Spherical, painted to look like the Death Star with the speaker cone being the D.S.'s reflector dish.

 

That would kick ass.

[Rowka]

Hahahahahaaahahahahah

 

Like this!

http://www.boingboing.net/2005/07/19/death_star_subwoofer.html

 

[takeout]

Originally posted by mlwarriner suppose you could elaborate? preferably in smaller words...

Standing waves are where different sound waves bounce around inside the cabinet and end up either cancelling or boosting certain frequencies in an undesirable manner. Hard surfaces and 90 degree corners are the culprits.

 

Simply put, if you put some sort of foam or batting in the cabinet, you break up those hard surfaces and corners. The waves get dissipated so that they don't become a nuisance. Parts Express sells poly fill batting, as well as sheets of high-density foam in various thicknesses (AcoustiStuff?). Burdizzos used the former on his Ultralight Cab.

[mlwarriner]

cool! thanks.

[takeout]

Originally posted by Rowka Hahahahahaaahahahahah Like this! http://www.boingboing.net/2005/07/19/death_star_subwoofer.html

I totally want to build one of these:

 

[Emprov]

 

Originally posted by takeout Parts Express sells poly fill batting, as well as sheets of high-density foam in various thicknesses (AcoustiStuff?). Burdizzos used the former on his Ultralight Cab.

 

 

I've built a few home audio speakers and have always been amazed at how much of a difference acoustic fill (and how and how much you put in) can make. I've literally been really bummed and pissed off at some speakers until I put some stuffing in them, totally harsh sounding. Then after the fill, heaven.

[lug]

The volume of the cab is the most important part. With batting, it doesn't really matter about shape too much. I have heard that you don't want a perfect square, even with batting but don't remember why.

[takeout]

Originally posted by lug The volume of the cab is the most important part. With batting, it doesn't really matter about shape too much. I have heard that you don't want a perfect square, even with batting but don't remember why.

All of the DIY audiophile nerd sites state that you should either build a cab with all-obtuse angles (like a pentagon), or using a ratio of 0.6:1:1.6 for the three dimensions. A perfect cube is the worst case scenario for standing waves.