Golden Rule????

[Higo]

Yesterday I was reading the Help of Speaker Workshop and I found the "golden rule". It says that the box size must have the relationship 1:1.6:2.5. What´s your opinion about this??? Is it something that you have to follow???
Marcelo.

[hifi]

there are several different ratios i believe that one is old...like ainchent egypt or so...

anyway you will have resonances att averey even multiple of the fundamental frequency if you use 1 1,6 2,5 u will spread them over three different frequencys

/micke

[kelticwizard]

Here is a past thread right here from this forum which should be helpful:
Box dimensions

[Ryder]

Well, Vance Dickason gives them as 2.6/1.6/1 (height,width,depth) so its close. He also privides 2/1.44/1 and 1.59/1.26/1 as alternatives. The idea is they avoid standing waves. He also says any improvement due to box dimension ratio will be secondary to well damped enclosure. See Ls Design Cookbook, p 100 6th edition.

[CHRIS8]

"He also says any improvement due to box dimension ratio will be secondary to well damped enclosure. "

While perfectly fine for sealed alignments, this does not account for the reduced inefficiency, or lower Qa, of a ported enclosure's output at and around tuned port frequency with increased acoustical damping material. However, if this loss of efficiency is acceptable then this is not a factor. I still try to use a design with non parallel, curved, etc. walls in any case where otherwise standing waves have to be dealt with in ported alignments in order to avoid using excessive amounts of damping.

Also, excessive amounts of acoustic damping in any alignment tend to suppress midrange frequencies on mid drivers, causing them to sound less dynamic IMO.

-Chris

[Ryder]

I agree Chris, can't say it all in a line or two. It's hard for some of us to use anything but rectangles unfortunately. Been working on my woodworkin a little - I agree. Also you do not necessarily need to use a great amount of damping materials to have well damped speakers. Just the the quality of of construction goes along way and it's very good to double up on the mdf. The feb issue of Audioxpress has an intersting article on that subject. Ive had good success using 1/2 inch furnature grade plywood on top of the 3/4 mdf too. Sounds good, no cracking. Solid as a rock.

Thanks for the interesting point.

Cheers