DX2 & Eminence 15" OB - diyAudio
Go Back   Home > Forums > Loudspeakers > Full Range

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 2nd May 2008, 04:59 PM   #1
britbug is offline britbug  United States
diyAudio Member
 
Join Date: Nov 2005
Default DX2 & Eminence 15" OB

I am thinking of doing a hybrid of the MJK open baffle projects that have received attention.
A Lowther DX 2, beefed up in the base with an Eminence Alpha 15 " combo, and crossed passively.
Does anyone know if :
2 15" per side will be enough, and whether I should use U or H frame on one or both?
Should I parallel or series the woofers?
ta

g
  Reply With Quote
Old 2nd May 2008, 05:06 PM   #2
diyAudio Member
 
Scottmoose's Avatar
 
Join Date: Mar 2005
Location: UK
How much is 'enough?' Not being awkward, just that it's something of a variable point so it's difficult to answer without more specific information.
__________________
Community site www.frugal-horn.com Commercial site www.wodendesign.com
  Reply With Quote
Old 2nd May 2008, 06:00 PM   #3
britbug is offline britbug  United States
diyAudio Member
 
Join Date: Nov 2005
I guess what I mean is make sure it is not bass-deficient in comparison to the > 200Hz of the DX2 (which is pretty efficient).

I can pad down the lowther a bit to suit (more than 2 woofers per side will make for a big speaker) but don't want to lose too much of their sensitivity either.

Good Q
  Reply With Quote
Old 2nd May 2008, 06:07 PM   #4
diyAudio Member
 
Taterworks's Avatar
 
Join Date: May 2007
You'll probably gain a good bit of flexibility by multi-amping, with a separate amp for your woofers. That's really the way you should go -- otherwise level-matching will be more difficult, and require more sophisticated math. If you multi-amp, you'll be able to just tweak it until it 'sounds right'.
__________________
If it works, but you don't know why it works, then you haven't done any engineering.
Taterworks Audio (nothing for sale)
  Reply With Quote
Old 2nd May 2008, 11:48 PM   #5
MJK is offline MJK  United States
Account disabled at member's request
 
Join Date: Feb 2002
Location: Clifton Park, NY
I did some quick numbers (less than 5 minutes invested) and found that a Lowther DX2 with a pair of Alpha 15A woofers per side would work in a reasonably sized (24" x 48") baffle with a passive crossover. You would get a system with 95.5 dB/w/m efficiency down to 50 Hz where it would roll off at 18 dB/octave. If done right this could be a real interesting passive OB system.


A U frame or H frame could be used to extend the bass lower but you would need to pad down the Lowther so the final system would loss a few dB in efficiency. I would stick with the simple OB geometry.

Hope that helps,
  Reply With Quote
Old 3rd May 2008, 01:02 AM   #6
ronc is offline ronc  United States
diyAudio Member
 
Join Date: Mar 2003
I have been running some sims on cuved U frames(vert curve) for OB applications using my curved mouth exit on horns programming. Its more of a tuning effect(think rear waveguide) with no resonance effect.
This was done for the accomplishment of the BVR/OB combo. Scott led me into the BVR application and i have been doing a study into the actions for various driver applications. Its interesting as there is no TL acton involved so the final action is an expansion of BR BW with a slight greater loading of the driver over a BR application (horn loading).

ron
  Reply With Quote
Old 4th May 2008, 10:44 PM   #7
diyAudio Member
 
Join Date: Sep 2005
What about this baffle?

Click the image to open in full size. Click the image to open in full size.

Mods:

1 - Bi-Amping

2 - Active filters (or digital filters from PC)

3 - 8" Fullrange high sensitivity (I have a couple spare FE206) instead of the Seas 90 dB mid driver

4 - 2 pairs of Alpha

5 - (optional) a pair of high efficiency compression drivers (B&C DE250?)

Target would be very high SPL at listening position. Would the Alpha be enough?
  Reply With Quote
Old 5th May 2008, 12:15 AM   #8
DaveCan is offline DaveCan  Canada
diyAudio Member
 
DaveCan's Avatar
 
Join Date: Nov 2005
Location: Moncton NB
Quote:
[i]Originally posted by thomaseliot [/i

Target would be very high SPL at listening position. Would the Alpha be enough? [/B]
Very high SPL's at the listening position is not a good idea for your hearing if your wanting to enjoy music for the years to come etc..
Dave
  Reply With Quote
Old 5th May 2008, 12:42 AM   #9
ttan98 is offline ttan98  Australia
diyAudio Member
 
Join Date: Apr 2006
Location: Melb
Quote:
Originally posted by DaveCan


Very high SPL's at the listening position is not a good idea for your hearing if your wanting to enjoy music for the years to come etc..
Dave

speakers with high spl is ok, you don't have turn the amplifier way up, listen at low level is still ok!
  Reply With Quote
Old 5th May 2008, 12:54 AM   #10
DaveCan is offline DaveCan  Canada
diyAudio Member
 
DaveCan's Avatar
 
Join Date: Nov 2005
Location: Moncton NB
Quote:
Originally posted by ttan98



speakers with high spl is ok, you don't have turn the amplifier way up, listen at low level is still ok!
Yep, I know that... Just made the comment because his ''Target'' is very high spl's at the listening position, and unless your wanting to fry your hearing??? Dave
  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
Why don't more of us use the 10" Eminence? Godzilla Full Range 8 8th March 2010 03:34 PM
What should I do with these? (15" Eminence) fusion Subwoofers 13 13th January 2007 08:48 PM
Enclosures for Eminence Sigma 18" and/or Eminence Kilomax 15", PA-sub application esaias Subwoofers 8 10th August 2005 05:17 AM
New Eminence "line-array" series? Ap Multi-Way 0 5th May 2004 12:53 AM
Which Eminence 10" JDeV Instruments and Amps 1 6th July 2003 06:50 PM


New To Site? Need Help?

All times are GMT. The time now is 02:18 PM.


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