line array + transmission line ? - 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 15th August 2006, 04:43 PM   #1
zobsky is offline zobsky  India
diyAudio Member
 
zobsky's Avatar
 
Join Date: Mar 2002
Location: Dallas, Tx, USA
Default line array + transmission line ?

I have a large number of 3" drivers coming my way and intend to try my hand at building a line array.

Searching this forum, I've seen instances of sealed, ported or open baffle line arrays. I'm wondering if a TL type might work too. Bill Fitzmaurice has something like this (TLAH). Like the TLAH, I intend to build mine to be corner loaded, but am considering a larger number of drivers (18 - 20 ) .

Questions regarding the bass-mid bass tuning:

1. I haven't yet got an idea of the driver paramters, but I'm suspecting an Fs of around 100 - 150 Hz. Let's assume a line length of 2 metres for convenience. In a TL loaded line array, .. the drivers are positioned pretty much all along the length of the pipe. Does it make more sense to partition the line into two smaller lines of 1 m each for a quarter wave line freq of 85Hz, or maintain a straight 2m line of 42 Hz qarter wave frequency. I realize that these numbers can be misleading as the drivers would load the line throughout its length, not just at the closed end.

2. Would it be better to taper the line, .. or mass load the terminus, or both.

3. Also, any reccomendations on the cheap 20c parts express onkyo tweeters vs. the apexjr tweeters (50c each i believe)

Sorry if the questions seem naive..

__________________
"Any fool can know. The point is to understand" - Albert Einstein
  Reply With Quote
Old 15th August 2006, 04:52 PM   #2
RJ is offline RJ  United States
diyAudio Member
 
Join Date: Oct 2004
Something like this?
Click the image to open in full size.

I beleve someone in England is building this.
As for the tweeters they're the same.
  Reply With Quote
Old 15th August 2006, 04:56 PM   #3
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
I recommend that you arrange centers of all drivers on a "curve" that represent a radius from your ears
  Reply With Quote
Old 15th August 2006, 06:28 PM   #4
zobsky is offline zobsky  India
diyAudio Member
 
zobsky's Avatar
 
Join Date: Mar 2002
Location: Dallas, Tx, USA
Quote:
Originally posted by RJ
Something like this?
.
.
I beleve someone in England is building this.
As for the tweeters they're the same.
Yes, .. that's one of the TL options i was considering, .. the other two being
1. mass loading the terminus with a port
2. maintaining two short TL sections (upper and lower), . without bothering with the extra folds as in your diagram.

As for a curved array suggestion, I'll fight that battle next, after deciding upon the bass alignment.
__________________
"Any fool can know. The point is to understand" - Albert Einstein
  Reply With Quote
Old 15th August 2006, 07:01 PM   #5
diyAudio Member
 
Join Date: Apr 2004
Location: Costa Rica
Send a message via AIM to johninCR Send a message via MSN to johninCR Send a message via Yahoo to johninCR
One of the projects on my todo list is to try one of my OB arrays as a TQWT. I believe that multiple drivers will help smooth out the typical lumpy Voight pipe response. Additionally, it would be a much easier construction than what you have pictured and the cab height for the array will be part of the line length.
__________________
Everyone has a photographic memory. It's just that most are out of film.
  Reply With Quote
Old 15th August 2006, 07:45 PM   #6
zobsky is offline zobsky  India
diyAudio Member
 
zobsky's Avatar
 
Join Date: Mar 2002
Location: Dallas, Tx, USA
Quote:
Originally posted by johninCR
One of the projects on my todo list is to try one of my OB arrays as a TQWT. I believe that multiple drivers will help smooth out the typical lumpy Voight pipe response.
Not sure if want to go voight pipe, but I was thinking along the same line ie. multiple drivers along the entire line should even out the peaks and dips.

I do wish the TL Gods (Dave, GM, Martin ...)would add their 2c of wisdom
__________________
"Any fool can know. The point is to understand" - Albert Einstein
  Reply With Quote
Old 15th August 2006, 08:10 PM   #7
diyAudio Member
 
Join Date: Apr 2004
Location: Costa Rica
Send a message via AIM to johninCR Send a message via MSN to johninCR Send a message via Yahoo to johninCR
The wings on my array are tapered, so it already has a TQWT shape and the conversion would be easy. A straight MLTL is an option as is a multi-driver BIB horn (see the fullrange forum). It just depends on how big you are willing to go with the footprint. As drawn yours looks more like a giant vent BR to me.
__________________
Everyone has a photographic memory. It's just that most are out of film.
  Reply With Quote
Old 15th August 2006, 09:50 PM   #8
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
As far as I know, in a TQWT it is very important where in the "line" you position the driver, so I guess LineArray isnt suited fore this
  Reply With Quote
Old 16th August 2006, 12:09 AM   #9
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
Why not simply make it into a double BR, the simplest is often the best, but admittedly not the most exciting
  Reply With Quote
Old 16th August 2006, 01:34 AM   #10
zobsky is offline zobsky  India
diyAudio Member
 
zobsky's Avatar
 
Join Date: Mar 2002
Location: Dallas, Tx, USA
Quote:
Originally posted by tinitus
As far as I know, in a TQWT it is very important where in the "line" you position the driver, so I guess LineArray isnt suited fore this
point taken, .. i agree that not all the drivers will be loaded equally (or even adequately) in an arrayed line, but various drivers along the line could possibly yield benefits by evening out the bass response . this is kind of a "shotgun" approach



Quote:
Originally posted by tinitus
Why not simply make it into a double BR, the simplest is often the best, but admittedly not the most exciting
i think an arrayed line would be as simple (or simpler) than a bass reflex
__________________
"Any fool can know. The point is to understand" - Albert Einstein
  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
how to combine Line array and transmission line together Jared Multi-Way 7 15th December 2012 01:20 PM
Transmission Line ADD ONS caratje Subwoofers 10 4th January 2006 09:49 AM
Line array tweeter line - On left or right? dhenryp Multi-Way 4 9th March 2005 11:35 PM
proposed transmission line array kneadle Multi-Way 12 25th July 2004 09:19 PM
t-line subs for a DIY line array tom1356 Multi-Way 17 28th December 2002 12:15 AM


New To Site? Need Help?

All times are GMT. The time now is 07:11 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