Help getting low. - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 6 Old 01-19-2013, 09:24 PM - Thread Starter
Member
 
Locoelectrician's Avatar
 
Join Date: Mar 2012
Posts: 99
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I have 2 behringer 18s that sound fantastic and shake everything but fall off pretty sharply around 40hz. I also have 2 pyramid WX-15X subs in generic boxes that struggle to hit 30hz. I've been using winisdpro to run scenarios with the 15s (as well as other 15s just for comparison) and the perfectly tuned box for my 15s is 12.4 cubic feet each!!! That makes them pretty much flat from 20hz up but there is no way I can have 2 boxes that size. What am I missing here? How are all these other subs hitting so low with such small enclosures? The specs for the WXs are. Fs(hz) 30.0, Qms 4.57, Qes 0.64, Qts 0.56, SPL 88.6, Vas 3.973. Unfortunately, I don't understand what these numbers mean and am simply relying on the software listed above. Any help would be greatly appreciated.
Locoelectrician is offline  
Sponsored Links
Advertisement
 
post #2 of 6 Old 01-19-2013, 09:53 PM
AVS Special Member
 
Jay1's Avatar
 
Join Date: Aug 2002
Location: AZ
Posts: 3,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked: 102
The high Qts paired with a Vas that isn't very low equals huge ported box. Its a sealed box woofer. Look for drivers with Qts around 0.4 or lower.
Jay1 is offline  
post #3 of 6 Old 01-19-2013, 09:56 PM
Advanced Member
 
nograveconcern's Avatar
 
Join Date: Aug 2012
Posts: 565
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 52
Quote:
Originally Posted by Locoelectrician View Post

What am I missing here? How are all these other subs hitting so low with such small enclosures?

Room gain and EQ, plus starting with a sub that is designed for HT. I didn't model your sub since it's missing a few critical specs like Le and X-max, but I'm going to guess that 12.4 cu ft is not perfectly tuned.
nograveconcern is offline  
post #4 of 6 Old 01-19-2013, 10:05 PM - Thread Starter
Member
 
Locoelectrician's Avatar
 
Join Date: Mar 2012
Posts: 99
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I modeled it in a sealed box and it still fell off around 35hz. They are a free experiment basically so I guess I need to shop for something to compliment the behringers and give me the lower notes.
Locoelectrician is offline  
post #5 of 6 Old 01-19-2013, 10:13 PM
AVS Special Member
 
Jay1's Avatar
 
Join Date: Aug 2002
Location: AZ
Posts: 3,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked: 102
That's good for a sealed box, but yes if you want strong response to 20Hz In a smaller box you likely need a different woofer
Jay1 is offline  
post #6 of 6 Old 01-20-2013, 07:03 AM
AVS Addicted Member
 
Bill Fitzmaurice's Avatar
 
Join Date: Nov 2009
Location: New Hampshire
Posts: 10,229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 1687
Quote:
Originally Posted by Locoelectrician View Post

I guess I need to shop for something to compliment the behringers and give me the lower notes.
Real HT subwoofers don't need 'complimenting'. Sell the Behringers to a DJ or band who can put them to work in their intended genre, use the proceeds to build HT subs loaded with decent quality HT sub drivers.

Bill Fitzmaurice Loudspeaker Design

The Laws of Physics aren't swayed by opinion.
Bill Fitzmaurice is offline  
Reply DIY Speakers and Subs

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

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