Go Back   Home > Forums > >

PA Systems A forum for discussion of all parts of a sound reinforcement or DJ system: loudspeakers, mixers (desks) etc.

18" superscooper in Hornresp
18" superscooper in Hornresp
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
Old 7th September 2021, 01:48 PM   #1
frangus is offline frangus  Australia
diyAudio Member
 
Join Date: Dec 2013
Location: Sydney
Default 18" superscooper in Hornresp

Can anyone recommend a starting point for modelling this horn in Hornresp?

Speakerplans.com

I'm not sure where to start as it's been several year since I've used Hornresp and need a "leg-up"...

Thanks
  Reply With Quote
Old 7th September 2021, 04:58 PM   #2
planet10 is offline planet10  Canada
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
18" superscooper in Hornresp
Click the image to open in full size.

The curved bit at the bottom is counterprodcutive and would be easier and better with a straight approximation.

dave
__________________
Stay safe. Stay home. Respect the 2m bubble.
  Reply With Quote
Old 7th September 2021, 07:08 PM   #3
David Morison is offline David Morison  Scotland
diyAudio Member
 
Join Date: Nov 2013
Location: Aberdeen, Scotland
On speakerplans.com's own forum: Database simulation - Speakerplans.com Forums - Page 1

I've not bothered to check the accuracy, but it should get you at least in the ballpark.
  Reply With Quote
Old 8th September 2021, 02:00 AM   #4
frangus is offline frangus  Australia
diyAudio Member
 
Join Date: Dec 2013
Location: Sydney
Quote:
The curved bit at the bottom is counterprodcutive and would be easier and better with a straight approximation.
Yeah, the curve would be invisible to the low frequency sound waves though I wonder if it's an attempt reduce air turbulence and noise as it exits the horn?

Quote:
On speakerplans.com's own forum: Database simulation - Speakerplans.com Forums - Page 1

I've not bothered to check the accuracy, but it should get you at least in the ballpark.
Thanks, I used to google to search the forum but didn't see that one. Ballpark is all I need at the moment. Once it's built I will measure properly.

Cheers
  Reply With Quote
Old 8th September 2021, 04:15 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
18" superscooper in Hornresp
Fhe “turbulence” the straight approximation would only affect the higher frequency. Stuff that is hopefully gone by the time it gets there.

If you aren’t moving them much you could do a stepped nagaoka-style strike-plate

dave
__________________
Stay safe. Stay home. Respect the 2m bubble.
  Reply With Quote
Old 8th September 2021, 11:31 PM   #6
ICG is offline ICG  Germany
Account disabled at member's request
 
Join Date: Jul 2007
Location: I had a Déjà Moo - I've seen that BS before!
Quote:
Originally Posted by planet10 View Post
The curved bit at the bottom is counterprodcutive and would be easier and better with a straight approximation.
That's definitely a reduction of the resonances. Okay, you could fill the space with polyurethane foam but I've done that one time and I can promise I will NEVER do that huge mess again! I'd replace it with a 45° angle board which is reinforced with triangle plates. But you are right, acoustically, the straight edges would hardly harm the sound though.
  Reply With Quote
Old 8th September 2021, 11:37 PM   #7
ICG is offline ICG  Germany
Account disabled at member's request
 
Join Date: Jul 2007
Location: I had a Déjà Moo - I've seen that BS before!
Quote:
Originally Posted by frangus View Post
Can anyone recommend a starting point for modelling this horn in Hornresp?

Speakerplans.com

I'm not sure where to start as it's been several year since I've used Hornresp and need a "leg-up"...
I'm not a hornresp veteran, though it's important to put the driver at the right distance of the horn length. At BLH the response can be vastly improved by an internal helmholtz absorber or by placing the driver not at the 'end' but a bit further into the length of the horn. Both instances are documented in several issues of the German DIY magazine 'Hobby Hifi'. I don't know the issue year/numbers though.
  Reply With Quote
Old 9th September 2021, 03:19 AM   #8
David McBean is offline David McBean  Australia
diyAudio Member
 
Join Date: Jun 2007
Quote:
Originally Posted by planet10 View Post
The curved bit at the bottom is counterprodcutive and would be easier and better with a straight approximation.
It would certainly be easier, but I am not sure that it would necessarily be better :-).

The page linked below may be of interest, particularly the FEM simulation results shown:

Big BenD Bass Horn: Design
__________________
www.hornresp.net
  Reply With Quote
Old 14th September 2021, 12:05 AM   #9
ICG is offline ICG  Germany
Account disabled at member's request
 
Join Date: Jul 2007
Location: I had a Déjà Moo - I've seen that BS before!
Quote:
Originally Posted by David McBean View Post
It would certainly be easier, but I am not sure that it would necessarily be better :-).

The page linked below may be of interest, particularly the FEM simulation results shown:

Big BenD Bass Horn: Design
I can promise you, the suggested change will not improve the subwoofer in any kind, form or shape. It's a half-a$$ed approach to make the build easier but doesn't have any positive approach on it. It is acceptable if you need an easier/much more simplified build of the scoop but leads to much more peaks and dips in the response because of the reflections within the horn, leading to interferences and resonances. If you want to use the upper range of the back loaded horn (which is the main purpose of a BL anyway) it's by far the worst thing you can do since it leads to a very 'wave-y' response with high peaks and dips. You can easily prove and forecast its very bad response in hornresp (software) or in AJHorn, it should be really avoided since you only get length resonances you have to deal with and get you very long decay ridges, which vastly muddy your bass up to your low mid range precision because of the phase difference. The impulse response in the upper bass/lower mids will also get squishy and boomy which results in having none advantage of the BL (scoop) horns.

BL horns are very delicate, It's not adviced to follow suggestions of inexperiecned 'read only' suggestions posters. You can get additional support on Speakerplans.com (register and ask) or other PA oriented pages. If you are aiming for high sound reproduction quality and not limited to Raggae or Dub, you're maybe better off with other subs anyway though.
  Reply With Quote
Old 15th September 2021, 06:54 AM   #10
KaffiMann is offline KaffiMann  Norway
Fanatic
diyAudio Member
 
KaffiMann's Avatar
 
Join Date: Sep 2009
Location: Grua, not far from Oslo.
18" superscooper in Hornresp
Quote:
Originally Posted by ICG View Post
That's definitely a reduction of the resonances. Okay, you could fill the space with polyurethane foam but I've done that one time and I can promise I will NEVER do that huge mess again! I'd replace it with a 45° angle board which is reinforced with triangle plates. But you are right, acoustically, the straight edges would hardly harm the sound though.
The one time I made a horn for a 12" woofer, I had no problems using PU foam.
I built it missing one side of the speaker, first I glued in place a piece of some kind of flexible flooring on the bends, gently misted the inside with some water, filled the gap with foam, cut off the excess with a large knife, glued on the side of the cabinet.
__________________
Clickable links to my music on Spotify or Bandcamp up to 24bit/96khz
  Reply to this post

Reply


18" superscooper in HornrespHide this!Advertise here!
Thread Tools

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
Whats a good hornresp input approximation for the "Karlsonator" ? freddi Subwoofers 1 29th July 2020 12:51 PM
can hornresp sim the "H-PAS" ? freddi Subwoofers 4 3rd June 2019 05:42 PM
is "closing off" a port in hornresp BP8P good 'nuff for comparing to BP6S? freddi Subwoofers 0 29th May 2019 10:18 PM
University "Dean" folded horn path, etc. for hornresp ? freddi Subwoofers 4 12th July 2018 07:15 PM
Hornresp adds significant LF response to all designs when using "multiple speakers" sine143 Subwoofers 12 10th January 2014 10:23 PM


New To Site? Need Help?

All times are GMT. The time now is 12:14 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Copyright ©1999-2021 diyAudio
Wiki