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

Multi-Way Conventional loudspeakers with crossovers

Line array project
Line array project
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 13th June 2003, 01:14 AM   #1
VictorG is offline VictorG  United States
diyAudio Member
 
Join Date: May 2003
Location: Albuquerque
Default Line array project

Okay guys I am about too build two line array speakers to fit in a relativly small college dorm. Basically I'm just double checking with the talent that is this forum to make sure there are no show stopppers.

I plan to put 10 of these apexjr ribbon tweeters on each:
http://www.partsexpress.com/pe/pshow...9-025&scqty=10



and 10 of these mid ranges on each.
http://www.partsexpress.com/pe/pshow...9-025&scqty=10


I have already built two killer base systems, and one will accompany this system depending on the final dimensions of my room.

Anyway, let me know if you see any inherent problems. Also, i am a little unclear as to wiring in seris/parellel arrangments to keep a constant ohm load. When I hook all this up in sets of seris and parallel, while I keep the same ohm load, am i driving the amp any harder? I.E. would I need more current? A friend of mine thinks there will be an inherant problem in this design.

Also, what can I do to help the tweeter get better dispersion? would mounting it into a custom horn help?

Does anyone have expirience with this tweeter and if so what are it's limitations, and where hav you crossed it over?

Thanks guys,
Brian
  Reply With Quote
Old 13th June 2003, 01:41 AM   #2
thylantyr is offline thylantyr  United States
diyAudio Member
 
Join Date: Feb 2001
Location: Mars
You should ask Jim Griffin on the
madisound.com forum since he's
experience with these designs.

I line sourced eight cheap planar
tweeters all in parallel for 1 ohm load
and my power amplifier drove the tweeters without problems. This is not
the normal way to do it, but it just goes
to show you that tweeters don't draw
alot of power and you can load down
the amplifier more than normal. But,
if you do the same thing paralleling
woofers, your amplifier would hate life.

If you haven't done so, you can ask
on the forum for *his* Linus Array
document, it's a good reference on
how to build one.
  Reply With Quote
Old 13th June 2003, 04:29 AM   #3
CharleyW is offline CharleyW
diyAudio Member
 
Join Date: Aug 2002
Location: Arlington, TX
Pardon me, but methinks that a 400HZ lower limit on those midranges is WAY too high.

You need something at least 80HZ (83 HZ is the lowest open string on a guitar when tuned to concert pitch - and the most frequent tuning is lower than that).

You need to get at least 60HZ out of the arrays (assuming these are for listening to music).

Just my opinion, feel free to slam away.
  Reply With Quote
Old 13th June 2003, 04:39 AM   #4
roddyama is offline roddyama  United States
diyAudio Moderator Emeritus
 
roddyama's Avatar
 
Join Date: Jan 2002
Location: Michigan
Quote:
Originally posted by CharleyW
Pardon me, but methinks that a 400HZ lower limit on those midranges is WAY too high.
Definately a show stopper. You're going to need 5" woofers (not mid-ranges) to get you down to 80Hz or so.
You also have the wrong link for the ribbons.

Here it is:
http://www.apexjr.com/speakerstuff.html
__________________
Rodd Yamashita
  Reply With Quote
Old 13th June 2003, 04:46 AM   #5
planet10 is offline planet10  Canada
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Line array project
Default Re: Line array project

Quote:
Originally posted by VictorG
why did you take the ribbon out of the provided chassis? what does this do for sound
Mostly to make them smaller... i never really listen to them unmodified.

Click the image to open in full size.
Quote:
Can I custom some horns for them?
I wouldn't do more than a waveguide built into the baffle and rear mount them... for a line array you really want to get them as close together as you can... it will be a pretty short array with only 10 tweeters.

Have you read Jim Griffin's white paper?

dave
__________________
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 13th June 2003, 01:18 PM   #6
VictorG is offline VictorG  United States
diyAudio Member
 
Join Date: May 2003
Location: Albuquerque
Default more details

Okay, so the reason I thought i would be able to make it with 400 Hz mids is because I have two different bass systems that I plan to pair up with these which each make it to ~21Hz. I was told at lower freq. the ear cannot tell where the signal is coming from (white paper) and thus, i could use my other bass systems. This is okay right?

I have compleated a sonotube project with 4 peerless drivers (pictures soon), and I expect two sonotubes to flank each panel. This is the bass which will most likely be employed with this array.

On the tweeters, your right, is is pretty short. I may go up to twenty tweeters on each. I have a far out idea of mixing twetters (i.e. these ribbons with bullets) to help dispurse the sound. I'm pretty sure I read somewhere this was a bad idea though, and any lines I've ever seen have been similar tweeters.

I've read the paper, and would love to purchase those planar drivers and get a long array the easy way, but alas, the pathetic moneteary exisatanse of a student if becoming a reality..... sigh.

Thanks for you continued replies guys.
Brian
  Reply With Quote
Old 13th June 2003, 03:59 PM   #7
nobody special is offline nobody special  United States
diyAudio Member
 
nobody special's Avatar
 
Join Date: Oct 2002
Location: USA
Sound begins to get directional at around 200Hz, so you need to go lower. I would go much lower, if possible, which means that you need some midwoofers as others have said. Even if you are using a steep crossover, those mids will be reproducing some bass. To keep the crossover predictable, each driver needs to be able to extend somewhat into the other driver's range.
Steve
__________________
Steve
  Reply With Quote
Old 13th June 2003, 08:22 PM   #8
JZatopa is offline JZatopa  United States
diyAudio Member
 
Join Date: May 2003
Location: Chicago
"Sound begins to get directional at around 200Hz"


From what I have experienced and have learned from other sources you can localize a sound source down to 80hz.
__________________
Knowledge is Power & Applied Knowledge is Freedom,
There is no higher religion than truth
  Reply With Quote
Old 13th June 2003, 08:40 PM   #9
roddyama is offline roddyama  United States
diyAudio Moderator Emeritus
 
roddyama's Avatar
 
Join Date: Jan 2002
Location: Michigan
The frequency at which sound starts to become directional will depend on a few factors. One is the size of the room. The larger the room, the lower will be the frequency for directionality. Another is the placement of the sub with relation to the main speakers. The frequency content and complexity of the music will also affect your ability to “find” the sub. The higher you x-over to the mid bass, the steeper your x-over slope (lo-pass) will need to be.

I cross to my stereo subs at about 90Hz with an 18db/oct xover in a 20’ X 18” room. When one of the sub channels when out, the stereo image began to shift around the sound stage, the sub became directional in the xover region.
__________________
Rodd Yamashita
  Reply With Quote
Old 14th June 2003, 07:04 AM   #10
The Paulinator is offline The Paulinator  United States
diyAudio Member
 
Join Date: Jan 2002
Location: Spfld, OR
I must say that I feel that the directionality of bass MOSTLY depends on the quality of the bass. If there is a noticeable amount of distortion that is rhythmically in sync with the bass, that upper frequency distortion gives diirectionality to the bass the same way that your mains are supposed to give directionality to the bass. I know that bass becomes directional at a high enough frequency (dunno what it is), but so often the quality of the bass causes directionality before frequency does.
  Reply With Quote

Reply


Line array projectHide 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
My Line Array Project Log zobsky Multi-Way 70 20th July 2013 08:02 AM
line array loudspeaker project daly2k Multi-Way 59 2nd February 2011 04:31 PM
Line Array Project SteveNarayan Multi-Way 4 14th March 2008 05:18 AM
Another Line Array Project Turboegt Multi-Way 43 30th June 2005 06:25 PM
my first HT project.... LINE ARRAY BABY Feandil Multi-Way 10 11th March 2005 07:26 PM


New To Site? Need Help?

All times are GMT. The time now is 01:20 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki