Dual horned sub cab ported design vs ported? - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers

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 16th October 2012, 06:43 AM   #1
diyAudio Member
 
Join Date: Oct 2012
Default Dual horned sub cab ported design vs ported?

so i was just curious on two subwoofer cab designs i have one is from the proven turbosound tsw 718 ad the other is from another unfinished website for speaker designs. i Really curious on your guys input of the ported vs unported design

<embed src="http://imageshack.us/slideshow/smilplayer.swf" width="426" height="320" name="smilplayer" id="smilplayer" bgcolor="FFFFFF" menu="false" wmode="transparent" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="id=imageshack/"/>
  Reply With Quote
Old 16th October 2012, 07:03 AM   #2
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
matthias... you need to fix your links or better still if they are just images is to upload them directly

Too add a photo.

First click "go advanced" in the box below the "quick reply" message box. Doesn't matter if you decide half way through a message to do that, it carries it foward.

Then click "Manage attachements". Maximise the new Window so that you can see all the text.

Click browse in the first box at the top and find your picture. Repeat for any more pictures.
Click upload... a message appears "uploading"
When complete the files will show as being attached. Now click the small text that says "close this window"

The pictures should now be attached and when you submit your post they will appear.

Make sure your pics aren't too big, a couple of 100k is plenty, and many members object when they are massive and it alters the margins
It tells you in the attachments window what max sizes are allowed.


If you want to attach a file that has a non standard format for example excel, circuit simulation etc then try putting the files in a zipped folder and attaching that.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 16th October 2012, 08:32 PM   #3
diyAudio Member
 
Join Date: Oct 2012
so i was just curious on two subwoofer cab designs i have one is from what i believe is the proven turbosound tsw 718 the other is from another unfinished website for speaker designs. i Really curious on your guys input of the ported vs unported design for a horned sub box.
Attached Images
File Type: png Carnivore_interior_unfinished.png (16.1 KB, 229 views)
File Type: gif double18bandpassmodifiedspeake.gif (7.3 KB, 223 views)
  Reply With Quote
Old 16th October 2012, 11:38 PM   #4
diyAudio Member
 
Join Date: Oct 2012
im really curious to opinions on the difference you might find between these to encloseurs although similar i assume they would give completely different results
  Reply With Quote
Old 18th October 2012, 02:02 PM   #5
epa is offline epa  Netherlands
diyAudio Member
 
Join Date: Apr 2010
Location: amsterdam
hi matthias
wel you have to simulate the driver to see if it works in each cab.
the ports in the left design is to limmit excusion at port tuning frequentie.
below that excursion rizes rapidly.
both are bandpass horns ,i guestimate the wil rol off at 50 or so ,looking at the short horn.
they wil be verry efficient.
__________________
one good thing about music ,when it hit you feel no pain.
so hit me with music
.
  Reply With Quote
Old 18th October 2012, 03:36 PM   #6
Djim is offline Djim  Netherlands
diyAudio Member
 
Join Date: Dec 2009
Location: 'Ollanda
Hi matthias125,

Ported horns are used for a long time. The ports are usually used to extend the bandwidth (bandpass) of such horn. An issue that should be considered with ported horns is that the excursion at the lowest part of the bandpass (there were the port is active) increases considerably.

What happens is that the efficiency of horn is traded for the less efficient port to give it a low end extension. Less efficient means that the driver needs to work harder to keep up with the rest of the horn-design. For instance, if you would use the same driver/concept of the Turbo Sound you mentioned and you would add a port, the frequency range (bandpass) could be extended but at cost of higher excursion. In practice that would mean the PD driver would run out of excursion very soon.

Tapped Horns also have two sides of the cone loaded. Therefore you can kind off compare them with ported horns. The difference is that Tapped Horns (sometimes described as a tapped pipe) have both sides of the cone loaded by the same horn/pipe. Since horns or pipes (both quarter wavelength resonators) are more efficient than ports (half wavelength resonator), the tapped horn becomes more efficient in the low end compared to ported horns. More efficient means lower excursion so the Tapped Horn will have more output in the lowest part of the bandpass, compared to a ported horn.The downside is that higher up the bandpass the 'true horn' of a ported horn becomes more efficient than the tapped horn.

In classic designs like the Nexo 1000 and 2000 range for instance, they also made use of a ported horn design. To prevent the excursion from going too extreme they made the ports smaller in diameter. In practice that would mean that the ports run into compression at high levels to prevent extreme excursion. This is a designer trick that needs careful study to make it work correctly. One needs to design for a specific driver and lots of testing needs to be done. The downside of this trick is that at high levels the low end stays behind. It works like a kind of dynamic EQ but than in a mechanical way.

Last edited by Djim; 18th October 2012 at 03:41 PM.
  Reply With Quote
Old 21st October 2012, 01:00 AM   #7
diyAudio Member
 
Join Date: Oct 2012
So the turbo sound design would be more efficient with less excursion? but the ported design could reach lower tuning freq more easily but at the cost of higher excursion risking the life of the driver?
  Reply With Quote
Old 21st October 2012, 05:44 PM   #8
Djim is offline Djim  Netherlands
diyAudio Member
 
Join Date: Dec 2009
Location: 'Ollanda
Hi matthias125,

"So the turbo sound design would be more efficient with less excursion? but the ported design could reach lower tuning freq more easily but at the cost of higher excursion risking the life of the driver"
Yes, that is right.

That is the reason why you see relative high tunings for so called ‘hybrid-horns’ (relative short horns with basreflex ports). Usually these basreflex port(s) are tuned at or above 50Hz for conventional 18" drivers.
  Reply With Quote
Old 21st October 2012, 06:28 PM   #9
diyAudio Member
 
Join Date: Oct 2012
Unfortunately im in love with the horizontal design. Making it easy to stack. So over all niether of these designs would be able to be tuned to 35hz?
  Reply With Quote
Old 21st October 2012, 07:57 PM   #10
epa is offline epa  Netherlands
diyAudio Member
 
Join Date: Apr 2010
Location: amsterdam
although the dynamic sound of a tru bashorn is almost unsurpassed,nowadays ,with the power cheaply available,its not realy nessecerry anymore.(imho)
a horn to 35 hz needs to be realy big(i,m talking thousands of liters)
you could always compromise/truncade the horn,and stack them but its still gona be big.
this is why the tapped horns are popular her at the diyaudio.
more efficient as bassreflex and much smaller then a front loaded horn.
if you still want to go for a flh ,you need to decide on driver type and see what you can do with it in simulation.
e
__________________
one good thing about music ,when it hit you feel no pain.
so hit me with music
.
  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
Micing a ported guitar/bass cab? qingcong Instruments and Amps 23 23rd March 2011 11:34 PM
Ported and sealed and horned, OH MY! MichiganMan Subwoofers 10 18th January 2011 04:13 PM
Thiele guitar cab vs. ported guitar cab qingcong Multi-Way 2 9th January 2011 03:32 PM
Dual chamber ported sub? elambert Subwoofers 12 18th May 2005 11:40 AM
Woofer Towers, front-ported or rear-ported? Goldenboy Multi-Way 6 15th June 2004 06:44 PM


New To Site? Need Help?

All times are GMT. The time now is 03:28 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