tuning boxes

How do you tune a ported box? If someone has a boz tuned to "35hz" what does this mean. What are the advantages and why do people do it.
thanks in advance

Replies (5)

SeVeNX7X on 03/27/2003 20:50:56
you tune a ported box by shortening / lengthening the port. if someone has a box tuned to 35Hz it means that the sub will sound best at 35Hz (35 phase changes/second, basically the sub moves in and out 35 times per second). The advantages are that you can tune the box to what the sub is sopposed to sound best at..

johnny2k3 on 03/27/2003 21:28:45
thanks but can you elaborate a little more please. How do i know when ive reached a certian frequency? say the subs i have should be in a ported box tuned to X freq. How do i know when i hit that X

SeVeNX7X on 03/28/2003 16:39:50
they have box making programs for the computer free of charge off the internet.. i think i used WinISD for mine.. you tell it how much airspace you need, the shape of the box you want, the freq you want to tune to, and it tells you all the dimensions, and how long and wide to make the port.

Swez on 03/29/2003 16:07:50
Sev is pointing you in a very good direction, Win ISD beta and Pro have a lot of power tools to help design a Primo sub enclosure for your subs.

I have yet to work with it to date, but understand that yes, is free and DL are available of the web. Basically, you plug in the Theil/ Small parameters of your sub into the proper fields and this program will calculate the optimal box size, port dimensions and anticipated output plots.

This program iis somewhat complex and not the easiest tool to learn... but if you have the time and inclination to build a Primo sub enclosure... this is the best tool I know of.

The other route you can go, is back to the sub maker (website or Tech Service) and see if they have box making recopmmendations for your subs. Search for the model number and then select the style of box you wish to use. Most name brand name makers have .pdf files with details on sub specs and box making recommendations... including tuning specs on their web sites. (Ie: Kicker, RF, Alpine and others)

For most car applications, ported boxes will net deep low bass at better than average SPL #'s. The size of the box is determined by the woofer specs and port tuning details are what you'll need to know. The Theils/Small parameters tell the primary details and the custom woofer enclosure data is based primarily on them.

I don't have the Win ISD web link handy... but maybe someone else here can supply that.

Swez

PS What subs are you working with now? Brand and model # w/ website is most helpful.

SeVeNX7X on 03/30/2003 09:31:24
http://www.linearteam.dk/default.aspx?pageid=winisd <-- there you go. That is the beta version. WinISD Pro is still in its Alpha version.. so there are a lot of bugs, and is not stable whatsoever, so this one will be the one you want =) have fun. good luck.