Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Thoughts on my isobaric "TL/Horn"box design:
Thoughts on my isobaric "TL/Horn"box design:
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
Thread Tools Search this Thread
Old 31st August 2011, 03:10 PM   #1
TheBaronGroog is offline TheBaronGroog  United Kingdom
diyAudio Member
Join Date: Aug 2011
Default Thoughts on my isobaric "TL/Horn"box design:

I impulse bought some old KEF B139 subwoofers on ebay a while back and have just started playing with ideas for an enclosure for the lounge. Enclosure must fit under some draws, so height and width dimensions are fixed-internal and depth we can play with. Subs must be mounted isobarically as old cathode ray TV above the enclosure will flip out if subs aren't mounted like this. External dimensions are:

H16.5"(fixed) W46.5"(fixed) D18.75" (couple of inches extra won't hurt, but will shift TV out of bay window into lounge and p-off the missus)

Thought I'd have my 1st go at a "T-line/folded horn" type of enclosure and was wondering what everyones thoughts are.

Line/horn starts at 1.25", increases to 2.5" at 1st bend, 5" at 2nd bend and 10" at final bend, opening in front of sub 20" wide and box height. Total length 160".

Now I have ZERO experience of this type of design, so figured that the line should start small and increase in width as it progresses through each bend, so the air speed should drop by half at each bend, though have seen designs where the pipe is the same diameter throughout or getting smaller towards the opening-but this would just require moving the internal walls so no fuss really!

And thanks to 60ndown for showing me the site
Attached Images
File Type: jpg TL.JPG (16.9 KB, 185 views)
  Reply With Quote
Old 31st August 2011, 05:34 PM   #2
oublie is offline oublie  United Kingdom
diyAudio Member
Join Date: May 2009
Location: Northern Ireland
have you used any modelling software such as horn resp?

do you know the thiele/small parameter of the driver?
There are 10 types of people in the world: Those who understand binary, and those who don't...
  Reply With Quote
Old 31st August 2011, 05:44 PM   #3
planet10 is offline planet10  Canada
diyAudio Moderator
planet10's Avatar
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Thoughts on my isobaric "TL/Horn"box design:
Scott & i did up a modern TL for B139. Three versions are here Transmission Line Speakers (Note: factory data is on the same site)

I would take the straight one, make the cross-section 1/4 to accomodate an isobarik pair, then fold and adjust as necessary to fit the driver. Or the triangular line and decrease cross-section by a factor of 2.

If that is too big to fit in your space, you will likely need to look at a different kind of box.

community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 31st August 2011, 05:54 PM   #4
TheBaronGroog is offline TheBaronGroog  United Kingdom
diyAudio Member
Join Date: Aug 2011
Oublie: No modelling software used to date, though have looked at hornresp and the maths looks preferable to learning how to use hornresp! Have used BBpro for years, but this is a new realm to me.

Planet10-thanks will have a look. Haven't been able to find the spec for these particular varient of the B139-though do have a woofertester so just need to pull the specs off them myself.

thanks for the advice
  Reply With Quote


Thoughts on my isobaric "TL/Horn"box design: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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
VOLT 15" woofer PORTED OR TL BOX?? domtweaker Multi-Way 47 9th July 2011 03:32 PM
who makes 18" x 12" x horn 3-w box??? mastadon Full Range 2 29th October 2009 09:31 PM
"Box" design and bracing for open baffle woofer array ryoshu Multi-Way 0 17th August 2008 07:07 PM
Krell's "Sustained Plateau" Design - some thoughts bear Solid State 19 1st November 2004 08:24 PM
Horn+TL DIY w/Scan-Speak 10" suiram Multi-Way 5 2nd April 2002 07:54 AM

New To Site? Need Help?

All times are GMT. The time now is 10:05 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio