Single sheet TH challenge - 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 24th July 2010, 06:59 PM   #1
jbell is offline jbell  United States
diyAudio Member
 
Join Date: Apr 2003
Location: .
Default Single sheet TH challenge

Ok, so being 'never satisfied' I'm trying to better 'the cube' that I just built a few of.

Since there are several hornresp tapped horn quarterbacks that are better than I.... Here's the challenge.

1. Single 4x8 sheet of plywood. All panels, including bracing/reflectors, etc..
2. Most SPL 'area under the curve' from 40hz-140hz (minimum 100db average +-3db 1W1M)
3. Minimum 125db single cabinet from 'about' 40hz on up in 2pi space (understand, some designs in single cabinet won't 'quite' be able to hit 40hz, that's ok...)
4. Under $200 driver.

Bonus points for a better shape than a cube.

EDIT:

This section of the original post will be used for navigating this thread, and will be updated occasionally.
This sub was designed for the eminence series of drivers, 4015lf, 3015lf, Kappa Pro 15-LF2. Others work too.

cad drawing --Single sheet TH challenge
General Layout --Single sheet TH challenge
cut sheet --Single sheet TH challenge
note about using PL premium poly glue -- Single sheet TH challenge
High pass filters and excursion -- Single sheet TH challenge
First thoughts on 'cone correction' -- Single sheet TH challenge
Directivity Testing -- Single sheet TH challenge
Non US driver, (monacor) -- Single sheet TH challenge
US Drivers/PowerRatings -- Single sheet TH challenge
Nice little comparison chart -- Single sheet TH challenge
One of my favorite pics of FlipC's dozen -- Single sheet TH challenge
Quick post about construction technique -- Single sheet TH challenge

Last edited by jbell; 8th October 2012 at 02:39 PM.
  Reply With Quote
Old 24th July 2010, 09:11 PM   #2
diyAudio Member
 
Join Date: Aug 2009
the cubo15 seems to do that pretty ok.

Cubo 15

it's very easy to built, maybe try one and compare to your cube ? I built the extended version with an 3015LF and the output is pretty damn good for that size.

just remembered, the extended version can't be built out of one panel, had to use a leftover piece for that.

Last edited by polviggen; 24th July 2010 at 09:14 PM.
  Reply With Quote
Old 25th July 2010, 02:33 AM   #3
diyAudio Member
 
Join Date: Nov 2007
Quote:
Originally Posted by polviggen View Post
the cubo15 seems to do that pretty ok.

Cubo 15

it's very easy to built, maybe try one and compare to your cube ? I built the extended version with an 3015LF and the output is pretty damn good for that size.

just remembered, the extended version can't be built out of one panel, had to use a leftover piece for that.
Just curious - how would you go about simulating the "Cubo" design in HornResp?
  Reply With Quote
Old 25th July 2010, 01:56 PM   #4
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
I don't buy the performance numbers presented.

Click the image to open in full size.

The larger EV MTL-1X with an 18 doesn't go as deep? Isn't as efficient?

Show me the sim !
__________________
Candidates for the Darwin Award should not read this author.
  Reply With Quote
Old 25th July 2010, 02:00 PM   #5
tb46 is offline tb46  United States
diyAudio Member
 
Join Date: Jan 2006
Location: Texas
Default Horn-vented bass reflex meets tapped horn.

Hi Brian,

Looks like a "horn vented bass reflex/tapped horn", see:

Novice stereo subs project with stereo amp.

Just take that Hornresp input (change to the respective numbers for driver, length and areas, if you like), and turn on TH.

Regards,
__________________
Oliver
  Reply With Quote
Old 25th July 2010, 03:28 PM   #6
diyAudio Member
 
Join Date: Aug 2009
hornresp is a bit negative on this type of enclosure. in reality it goes lower

here are the inputs i got
Attached Files
File Type: txt cubo15_3.txt (430 Bytes, 550 views)
  Reply With Quote
Old 25th July 2010, 07:49 PM   #7
jbell is offline jbell  United States
diyAudio Member
 
Join Date: Apr 2003
Location: .
johan (rademakers) posted something VERY similar to the cubo in one of the TH threads way back.. I'm too lazy to look it up right at the moment. My problem with most of the hybrid cabinets are they are 50hz boxes, and it takes a pile of them to get to 40hz.

Because of that, I have kinda dismissed a hybrid... but maybe I should play around with a large chamber/short horn and see if there is something there I haven't seen in the past. I've also played around with compound horns at 3:1, and found something similar... Just hard to get to 40hz.

The folding is also the trick.. how to most efficiently fold with the fewest boards possible, while still having a good performing cabinet.

any creative thoughts?
  Reply With Quote
Old 25th July 2010, 09:40 PM   #8
diyAudio Member
 
Join Date: Aug 2009
that probably was the cubo
  Reply With Quote
Old 25th July 2010, 10:35 PM   #9
Xoc1 is offline Xoc1  United Kingdom
diyAudio Member
 
Xoc1's Avatar
 
Join Date: Nov 2008
Location: Devon UK
My attempt
12mm Ply 1off 8' x 4' sheet Eminence 3015LF driver
Trouble is that as you tweek the bandwidth and efficiency you loose the low frequency extension. The only way I can see to get it back is to increase the size which would take more timber....
Maybe a longer path length would be possible if the width of the horn was reduced to 400mm
Spl response grey line is J Bell Mini TH for comparison.
Attached Images
File Type: jpg Hornresp TH JBC.jpg (192.6 KB, 7437 views)
File Type: jpg Tapped Horn Mini 15 JBC.JPG (144.1 KB, 7263 views)
File Type: jpg Cut Sheet JBC.jpg (78.0 KB, 6998 views)
__________________
My daughters music
http://soundcloud.com/zoey-phillips
  Reply With Quote
Old 25th July 2010, 10:49 PM   #10
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
The 'iron law' still applies to a TH enclosure.

I don't think 40hz and 100dB are possible from a 2' cube.

50hz, yes, 40hz, no.

#9 is a good example of that at 90dB at 40hz.

"in reality it goes lower"

With room gain, I might buy that. In 2Pi or 4Pi, no way.
__________________
Candidates for the Darwin Award should not read this author.

Last edited by djk; 25th July 2010 at 10:52 PM.
  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
Here is a Challenge latala Solid State 41 12th May 2011 01:13 AM
Renovation Challenge ZirconiumZephyr Multi-Way 16 1st September 2009 08:38 AM
Design Challenge #1 kgillies Subwoofers 12 13th June 2007 03:20 PM
a challenge --or I need help lawrence99 Car Audio 0 9th March 2005 04:44 AM
The challenge ! thylantyr Solid State 51 24th July 2003 08:41 PM


New To Site? Need Help?

All times are GMT. The time now is 09:29 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