Horn/TL combo - Page 40 - 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 30th November 2012, 02:57 AM   #391
...truth seeker...
diyAudio Member
 
Ed LaFontaine's Avatar
 
Join Date: Feb 2004
Location: where the Appalachians rise from the Blue Grass
You may display more response detail in the Frequency graph. To do this reset the range of the graph. Clicking on it will allow you to enter different values where you have 110 & 60 now. I suggest 105 & 75 for 3 dB gradations or 104 & 84 for 2 dB gradations.

Varying Zdriver may have an effect upon the response ripple around 500 Hz.

You may consider a slot port as an alternate to an 8" diameter round port. Your locating the port close to the floor is favorable IMHO. I plan to investigate the use of an oversize slot port and stuff it lightly for tuning purposes. YMMV

Last edited by Ed LaFontaine; 30th November 2012 at 03:05 AM.
  Reply With Quote
Old 30th November 2012, 07:38 AM   #392
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Thanks for the comments. I am clearly new to the program. Is i tpossible to model a slot or do you just figure volume of the port. WinIsd lets you use double ports. With this, i was just playing with total vloume of the port. Next time i will post the impedance plot sas well to discuss what they mean an dhow they should look.

Your port idea is basically similar to aperiodic loading, correct. ZM posted a TQWT with large volume slot earlier.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 30th November 2012, 12:04 PM   #393
...truth seeker...
diyAudio Member
 
Ed LaFontaine's Avatar
 
Join Date: Feb 2004
Location: where the Appalachians rise from the Blue Grass
I think it depends on your software. It appears you are using an older version of worksheet. Martin now provides worksheets which are based upon the volume components, Area & length.
  Reply With Quote
Old 30th November 2012, 01:03 PM   #394
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
I have his newest sheets. In the MLTL worksheet, it only has an option for port radius and length. Further down, you can fine tune the box parameters for in room response, but none of the changes made there affect the upper response graphs which I showed. I assumed that this was to mean that if you wanted other shapes, you would have to just figure volume.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 30th November 2012, 02:11 PM   #395
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Quote:
Originally Posted by Ed LaFontaine View Post
Varying Zdriver may have an effect upon the response ripple around 500 Hz.

You may consider a slot port as an alternate to an 8" diameter round port. Your locating the port close to the floor is favorable IMHO. I plan to investigate the use of an oversize slot port and stuff it lightly for tuning purposes. YMMV
Right on. MJK's math dictates a L*0.349 location, which only considers length while mine factors in CSA, so varies depending on the aspect ratio and since this cab doesn't have a very high one, it calculates L*0.487, even lower down than a golden ratio's L*0.46233, so no significant 1/4 WL vent loading unless the driver, vent is at the extreme ends. Plus, there’s the room’s vertical modes to consider WRT driver location.

Hmm, I figured a slot vent was planned since a 4" radius vent was located 2" off the bottom.

Coming from a 'critically' damped reflex vent oriented time, all my large vent alignments have/had them, so still recommend them when appropriate, though most folks want to take the extra time/effort required to tune a duct when they can temporarily slide in different length tubes to find the best overall vent length.

For sure, if a maximally flat alignment such as this one is used in a wall or corner loaded app it will tend to sound a bit 'boomy' [AKA 'west coast sound'] typical of many old Altec, JBL consumer products once BSC is dialed in.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 30th November 2012, 03:01 PM   #396
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
I was just playing with the program. Next try will be 15ft^3, that 24x32x37, with driver 1/3 way down. I'll also play with mankinf port longer and see how the affects tuning. If there is a way to use square port, I would love to know.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 30th November 2012, 10:14 PM   #397
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
..... not bad at all
Attached Images
File Type: jpg 1.jpg (72.9 KB, 127 views)
File Type: jpg 2.jpg (11.8 KB, 125 views)
File Type: jpg 3.jpg (91.3 KB, 125 views)
File Type: jpg 4.jpg (100.7 KB, 123 views)
File Type: jpg 5.jpg (61.5 KB, 117 views)
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM

Last edited by Zen Mod; 30th November 2012 at 10:17 PM.
  Reply With Quote
Old 30th November 2012, 11:26 PM   #398
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Couple of questions.

How important is consistency of wavelets(?) of the first two impedance graphs?

How do you determine port tuning? I have been using WinIsd. I dont know how to model aperiodic tuning.

Here is try using better box ratio. Cant figure out why acoustic impedances are so ugly and why there is nasty port phase issue
Attached Files
File Type: doc 2nd Try.doc (122.5 KB, 13 views)
__________________
...Shape the sound , Man!
  Reply With Quote
Old 1st December 2012, 08:42 AM   #399
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
let GM say last word here

I'm sort of short in time today , besides fact that I have no clue , comparing to him

observe difference in length of your TL and mine

your's is too short
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 1st December 2012, 09:22 AM   #400
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
The length is indeed major differennce, but if i have read right. The porit acts as a sort of inductive loading, lengthening what would be a shorter pipe, making it similar to tapered down pipe. I assume you would just fold you tl in half, correct.
__________________
...Shape the sound , Man!
  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
Need Help w/ Bass Cabinet for TAD TL-1102 & TL-1601a. Use w/ TD-4001 & Yamamoto Horn HP8903B Multi-Way 11 22nd February 2011 07:20 PM
50s - 60s Woofer/horn combo drivers toptip Full Range 1 22nd June 2010 02:07 PM
Will this horn/driver combo beam? Defo Multi-Way 29 10th May 2010 04:26 AM
adding dome tweeters to altec horn combo ke4mcl Multi-Way 3 28th April 2009 03:34 PM
DE250 and Horn combo tested here ttan98 Multi-Way 5 11th April 2008 02:12 AM


New To Site? Need Help?

All times are GMT. The time now is 05:26 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