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

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
Thread Tools Search this Thread
Old 23rd June 2011, 04:12 PM   #11
jbell is offline jbell  United States
diyAudio Member
Join Date: Apr 2003
Location: .
Originally Posted by tb46 View Post
Hi jbell,

Did you ever get around to doing something like a polar plot for the SS15?

I got out the string and the spl meter... but got lazy and only marked 90 and 180 degree marks at a couple key frequencies that is in the 'directivity' area of the chart below.

besides, at the time I originally posted it -- art was arguing that my house at the end of a 100' extension cord away was affecting my readings.. so I'm pretty sure if I were to make the effort to actually do a polar plot, well, I don't think many would accept it. I also found the upright vs side more enlightening than even a polar plot, as the 50hz response is much better on side, and makes the box sound 'lower.'

Click the image to open in full size.
  Reply With Quote
Old 23rd June 2011, 04:33 PM   #12
nigelwright7557 is offline nigelwright7557  United Kingdom
diyAudio Member
nigelwright7557's Avatar
Join Date: Apr 2008
Location: Carlisle, England
The problem with horn speakers is the size and weight for a mobile disco.

I have always stuck to plain speaker boxes so they will fit in the motor.

I use a Fane collossus 18 incher and a Eminence sigma pro 18 incher for bass in ported cabinets.
PCBCAD51 pcb design software. 2018 version out now >>>>>> http://www.murtonpikesystems.co.uk
  Reply With Quote
Old 23rd June 2011, 05:37 PM   #13
Djim is offline Djim  Netherlands
diyAudio Member
Join Date: Dec 2009
Location: Les Pays-Bas
Originally Posted by nigelwright7557 View Post
I use a Fane collossus 18 incher and a Eminence sigma pro 18 incher for bass in ported cabinets.
SS15: 50Hz-250Hz (103dB) usable from 38Hz, 240 litre cab
THAM: 48Hz-140Hz (100dB) usable from 35Hz, 185 litre cab
MTH-30: 57Hz-280Hz (100dB) usable from 47Hz, 115 litre cab

Last edited by Djim; 23rd June 2011 at 05:49 PM.
  Reply With Quote
Old 23rd June 2011, 06:07 PM   #14
tb46 is offline tb46  United States
diyAudio Member
Join Date: Jan 2006
Location: Texas
Default SS15 Directivity

Hi jbell,

Naturally, measurements can always be improved upon, but yours are good enough for me, and a heck of a lot better than guessing. It would still be nice to have at least the front and back on axis @ 1 and 10m.

  Reply With Quote
Old 30th January 2013, 12:47 PM   #15
systemaap is offline systemaap
diyAudio Member
Join Date: Jan 2013

This an old problem. Part of it is that normal subs are non-directional, part is that the DJ/PA is typically near walls, where there is additional room gain for bass. while the middle of the dance floor is always a "bass hole".

To make low bass directional you need either massive horns (and I mean massive, look up the Levan Bass Horn) or subs that use active steering.

Levans and their ilk are severely unportable, active pattern steered subs need multiple amp's and are uncheap.

In the 80's I found that the classic JBL dual 15" "scoop" worked okay for punchy bass across the dance floor (preferably one in each corner), but they do not really go low and they are still rather large, large enough you really want them only for installed sound.

Some may laugh, but the old Karlson coupler does seem to have a few dB gain in the mid-bass over normal reflex boxes and it's weired distortion behaviour makes them sound "lower" than they really go. One can get pretty punchy PA bass out of them, they do like fairly light cones (EVM15L for example) and no floor shaking, but at least they are semi-portable.

i can make the floor shake with mine karlsons.
Click the image to open in full size.
  Reply With Quote


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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Murray the K's Disco on Wheels diamondzzzz Introductions 3 25th June 2012 01:33 AM
Adding subwoofer to mobile disco, help please wheatgerm Subwoofers 7 5th December 2009 02:39 AM
A valve pre amp for my disco and electric guitar. nigelwright7557 Instruments and Amps 4 12th June 2008 11:44 PM
Moving Head Disco Light... TroelsM Everything Else 8 30th November 2005 04:30 AM
Dynamic Bullet tweeters for pa/disco Bull Multi-Way 3 29th November 2002 01:38 PM

New To Site? Need Help?

All times are GMT. The time now is 09:03 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio