Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

JBL4607 4507 port mod, w/wo 3015lf
JBL4607 4507 port mod, w/wo 3015lf
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 6th May 2014, 01:51 PM   #1
screamersusa is offline screamersusa  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Fort Collins Colorado
Default JBL4607 4507 port mod, w/wo 3015lf

Since time is not on my side....

I can have a 4507 box, but I believe its a 4607? It has a 2225h and the two way xover in it so I assume its not set up as a sub.
Does anyone have the correct port size for the 4507 w the jbl and the modded
port size for a 3015lf handy? looking for 80-100hz and below.

Gotta either use the 2225 for now or borrow the 3015lf from another cab as a temporary solution while I build something more long term that fits in an suv.
I'll be keeping the box to go with a couple of stage monitors later along with a
gemini 400 bi amped amplifier bolted to the back.
  Reply With Quote
Old 6th May 2014, 04:06 PM   #2
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
This says it's tuned to 40 Hz, a ~standard in prosound/cinema apps and changing drivers only potentially changes F3, mid-bass response flatness.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 6th May 2014, 05:11 PM   #3
Inductor is offline Inductor  Portugal
diyAudio Member
 
Inductor's Avatar
 
Join Date: Feb 2006
Location: Cascais
Change the size of the ports (double the length). As you don't want to do this, or can't because of int. dimensions, then reduce the number of ports to half so that you have only two ports with the same length (block the other two so that you can use the speaker later).
With the JBL you had tuning to 40Hz and F3 43 Hz (JBL 2226H),
with Eminence KappaLite3015LF you have 30Hz tuning and F3 47 Hz but with better LF extension.
  Reply With Quote
Old 6th May 2014, 06:05 PM   #4
screamersusa is offline screamersusa  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Fort Collins Colorado
Thanks, that makes this cab look usable for now. Plugging ports is always a cool way to go keeping the cab intact.
If I were crazy enough, and if there was room, would doubling the port length via a 90 degree smooth elbow like JBL did on some studio monitors increase the overall output a couple db?
Pulling the crossover box out (if its in a box) would replace some of the lost volume.
  Reply With Quote
Old 8th May 2014, 02:53 PM   #5
weltersys is offline weltersys  United States
diyAudio Member
 
weltersys's Avatar
 
Join Date: Jan 2008
Location: Florida
Quote:
Originally Posted by screamersusa View Post
1) Plugging ports is always a cool way to go keeping the cab intact.
2)If I were crazy enough, and if there was room, would doubling the port length via a 90 degree smooth elbow like JBL did on some studio monitors increase the overall output a couple db?
1)Plugging ports lowers tuning, but increases chuffing, and using a driver with higher Xmax will "blow out" the ports at high volume.
2) Doubling port length will lower Fb, output will go up slightly at the lower tuning but be reduced above.
  Reply With Quote
Old 8th May 2014, 04:18 PM   #6
Inductor is offline Inductor  Portugal
diyAudio Member
 
Inductor's Avatar
 
Join Date: Feb 2006
Location: Cascais
Quote:
Originally Posted by weltersys View Post
1)Plugging ports lowers tuning, but increases chuffing, and using a driver with higher Xmax will "blow out" the ports at high volume.
2) Doubling port length will lower Fb, output will go up slightly at the lower tuning but be reduced above.
Nonsense, ports are over dimensioned. (NPI)
  Reply With Quote
Old 8th May 2014, 04:49 PM   #7
screamersusa is offline screamersusa  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Fort Collins Colorado
Quote:
Originally Posted by weltersys View Post
1)Plugging ports lowers tuning, but increases chuffing, and using a driver with higher Xmax will "blow out" the ports at high volume.
2) Doubling port length will lower Fb, output will go up slightly at the lower tuning but be reduced above.
That will probably work as they will be under modded PV15's and crossed either 65hz via a mackie 1400I or through a tdm crossover. It'll probably get me by for the moment till life stabilizes and I can get a van. Building a pair of ss15 or even thams would be better but I don't have the luxury of a workspace anymore. Bjornosubs probably wont fit in the SUV either.
  Reply With Quote
Old 8th May 2014, 06:40 PM   #8
weltersys is offline weltersys  United States
diyAudio Member
 
weltersys's Avatar
 
Join Date: Jan 2008
Location: Florida
Quote:
Originally Posted by screamersusa View Post
Building a pair of ss15 or even thams would be better but I don't have the luxury of a workspace anymore. Bjornosubs probably wont fit in the SUV either.
Since you don't have a workshop or a van, how about a van, trailer and complete system including subs ?

Complete Line Array System for Sale

Hope business is looking up for you!

Art
  Reply With Quote
Old 8th May 2014, 07:24 PM   #9
tb46 is offline tb46  United States
diyAudio Member
 
Join Date: Jan 2006
Location: Texas
Default JBL 4507 Port Mod

Hi Y'all,

I may be looking at this all wrong, but, if the data on the ports I found @ audiokarma is correct, the port particle velocity on the unmodified 4507 is already on the high side (@ Xmax), w/ the 3015LF it gets to be clearly too high (@ Xmax). Take a look at the two attached Hornresp records, and, please, let me know what I got wrong here, or what you consider appropriate port particle velocities for PA purposes.

My guess would be 4ea. 4"Dia. x 12" long ports.

Regards,
Attached Images
File Type: jpg 4507_dims_port_2003_audiokarma_doucanoe.jpg (58.7 KB, 133 views)
Attached Files
File Type: txt 1jbl4507.txt (981 Bytes, 18 views)
File Type: txt 2jbl4507.txt (979 Bytes, 12 views)
__________________
Oliver

Last edited by tb46; 8th May 2014 at 07:32 PM.
  Reply With Quote
Old 8th May 2014, 08:40 PM   #10
weltersys is offline weltersys  United States
diyAudio Member
 
weltersys's Avatar
 
Join Date: Jan 2008
Location: Florida
Oliver,

The 4507 was designed for use with the JBL 2225 which has only 5.08mm Xmax, I'd agree that almost doubling Xmax (3015LF has 9.6 mm Xmax) would require larger port volume if one wants to take advantage of the output the additional excursion avails rather than create four fan jets :^).

What Fb did you guess would result with 4ea. 4"Dia. x 12" long ports?

Art

Last edited by weltersys; 8th May 2014 at 08:48 PM.
  Reply With Quote

Reply


JBL4607 4507 port mod, w/wo 3015lfHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
What should I do with (2) 3015lf's? m R g S r Subwoofers 1 23rd August 2012 06:41 AM
Wicked One WO 32 - Subwoofer BTW Subwoofers 21 17th May 2012 12:39 AM
Vifa P21 WO-12 woofers. nodiak Swap Meet 1 3rd January 2009 04:11 PM
Speakers FS: 16pcs HiVi M8a 2pcs Vifa P25-WO-00-08 Bent Swap Meet 9 9th June 2008 02:15 PM
Comments on Decware WO-32 subwoofer? mjgraves Subwoofers 2 6th August 2002 03:38 AM


New To Site? Need Help?

All times are GMT. The time now is 11:09 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki