tunning of a ported box will be the same for all sub sizes ? - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 9th January 2005, 11:50 PM   #1
diyAudio Member
 
Diy_Ambitious's Avatar
 
Join Date: Sep 2004
Location: NZ
Default tunning of a ported box will be the same for all sub sizes ?

OK , I was searching around on how to tune ported boxes and came across this site

http://www.clubknowledge.com/Car_Audio_FAQ/?t16

So, for example if I got a ported box for an 8" tuned to 35hz. If I put a 6.5" inch or another sub bigger will it still be at 35hz ? Do I loose or gain any efficientcy by using a smaller or bigger ported box ?
  Reply With Quote
Old 10th January 2005, 03:39 AM   #2
diyAudio Member
 
Join Date: Jul 2004
Location: BC, Canada
The short answer: Pretty much.

The box is tuned to a certain frequency because of the volume of air in the box, not because of the size of the driver. I say pretty much, because the vilume displacements of the two woofers would be slightly different.
  Reply With Quote
Old 10th January 2005, 06:08 AM   #3
diyAudio Member
 
BassAwdyO's Avatar
 
Join Date: Jun 2004
Location: Illinois
Send a message via AIM to BassAwdyO
as bigmike said, the box tuning itself is an effect called resonation due to the system acting as a mass and a spring. the mass is the air inside the port, while the spring is the air inside the enclosure. This is why box volume is calculated without including port volume. A frequency response graph shows the sensitivity/bandwitdth of a speaker/enclosure system. You can find modeling programs like winISD that will do the work for you, all you have to do is enter in driver parameters, box size, and tuning frequency. Frequency response graphs use frequency on the x axis and sound intensity(in dB) on the y axis.
__________________
The golden rule of DIY:
Build nice, or build twice!
  Reply With Quote
Old 12th January 2005, 02:58 AM   #4
diyAudio Member
 
Join Date: Jul 2003
Location: Silicon Valley
The tuning doesn't depend on the driver size per se, but in practice bigger speakers tend to require bigger boxes. You need to read up on Thiel/Small (TS) parameters.
__________________
Davy Jones
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
what are some sealed and ported box sizes you can suggest for this speaker ? zuki Subwoofers 17 8th March 2007 05:51 PM
Frequency tunning. perpetual Subwoofers 2 22nd June 2005 03:22 AM
sub tunning perpetual Subwoofers 3 20th June 2005 11:07 AM
What happens with different port tunning andy2 Multi-Way 15 28th December 2004 06:09 PM
Woofer Towers, front-ported or rear-ported? Goldenboy Multi-Way 6 15th June 2004 06:44 PM


New To Site? Need Help?

All times are GMT. The time now is 06:11 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2