Port design flange question - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

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 31st October 2003, 06:26 PM   #1
TheoM is offline TheoM  United States
diyAudio Member
 
Join Date: Mar 2003
Location: Ohio
Default Port design flange question

Anyone. How does the flange impact a port length. Does the design length stop where the flange begins, or do I count the flange area?

Also, I have a situation where the port is close to the driver. Its a 4" x 2" port. Do I need to block the area between the rear of the port and the rear of the driver? I'm concerned about phase cancel.
  Reply With Quote
Old 31st October 2003, 08:09 PM   #2
Nuuk is offline Nuuk  United Kingdom
diyAudio Member
 
Nuuk's Avatar
 
Join Date: Feb 2003
Location: Somerset, SW England
Quote:
Anyone. How does the flange impact a port length. Does the design length stop where the flange begins, or do I count the flange area?
In short - it doesn't really matter!

Quote:
Also, I have a situation where the port is close to the driver. Its a 4" x 2" port. Do I need to block the area between the rear of the port and the rear of the driver? I'm concerned about phase cancel.
In theory, you are right to question this but I have heard a number of great sounding speakers with the port adjacent to the woofer with seemingly no ill-effects!

Personally, I prefer to keep the port as far from the driver as possible and after experimenting, I now prefer putting the port on the bottom of the speaker.
__________________
The truth need not be veiled, for it veils itself from the eyes of the ignorant.
  Reply With Quote
Old 2nd November 2003, 06:52 AM   #3
TheoM is offline TheoM  United States
diyAudio Member
 
Join Date: Mar 2003
Location: Ohio
Default Port location and phase alignment

I'm sensitive to phase alignment problerms. I always put the port in the same plane as the driver. I think this improves the impact of low end. But.... this is one man's opinion. Punch. I like it. tvm
  Reply With Quote
Old 2nd November 2003, 07:15 AM   #4
diyAudio Moderator Emeritus
 
roddyama's Avatar
 
Join Date: Jan 2002
Location: Michigan
Default Re: Port design flange question

Quote:
Originally posted by TheoM
Anyone. How does the flange impact a port length. Does the design length stop where the flange begins, or do I count the flange area?
FWIW, my Bass Box Pro shows a ~5% length reduction for one end flared and ~10% length reduction for both ends flared (length includes the flare).
Quote:
Originally posted by TheoM
Also, I have a situation where the port is close to the driver. Its a 4" x 2" port. Do I need to block the area between the rear of the port and the rear of the driver? I'm concerned about phase cancel.
No, you don't need to block off the port from the driver inside the box. The air in the port will resonate at it's tuned frequency providing the proper low frequency output. The ports output is out of phase with the driver by design.
__________________
Rodd Yamashita
  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
L-shaped port for vented design runethechamp Multi-Way 3 27th May 2009 05:11 AM
Flange schematic amelecsol2000 Instruments and Amps 7 16th March 2008 12:51 AM
What 104mm flange tweeters do I NEED to hear? TurboFC3S Multi-Way 8 19th July 2007 07:13 PM
How to design port without driver parameters jedcrocker Multi-Way 2 27th December 2004 02:24 PM
port design pkgum Multi-Way 15 1st January 2002 02:34 PM


New To Site? Need Help?

All times are GMT. The time now is 06:52 AM.


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