Subs for my PA system (an ohm question) - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs 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 2nd November 2007, 01:09 PM   #1
diyAudio Member
Join Date: Sep 2007
Default Subs for my PA system (an ohm question)

I am putting new 15" raw speakers in existing cabinets to run as subs for my band's PA system. The issue I am having is I can only find 8 ohm speakers, and I want 4 ohm speakers.

I am no expert at ohm loads, but I have always been told there is no way to lower the ohm load, only increase it correct? So if I buy two 8 ohm speakers and run them bridged out of a QSC 2450, I will be at an 8 ohm load and restricted to 8 ohm wattage output correct?

Is there any way around this other than find (and pay for) 4 ohm speakers?

The second question is with the 8 ohm speakers be effective with the QSC 2450?
  Reply With Quote
Old 2nd November 2007, 02:53 PM   #2
diyAudio Member
Join Date: May 2007
Send a message via MSN to Lord_Humongous
Two 8 ohm speakers connected in parallell will result in a 4 ohm load.
"In a world gone mad, only a lunatic is truly insane..." - H.J.S.
  Reply With Quote
Old 2nd November 2007, 09:13 PM   #3
diyAudio Moderator
Cal Weldon's Avatar
Join Date: Jan 2004
Location: Near Vancouver
Hi KP,

Not sure where you picked up that little tidbit but Lord H is correct. Two 8 ohm in parallel results in a 4 ohm load. Two 8 ohm in series is a 16 ohm load.
planet10 needs your help:
Let's help Ruth and Dave
  Reply With Quote
Old 3rd November 2007, 06:38 AM   #4
Foxx510 is offline Foxx510  Australia
diyAudio Member
Join Date: Nov 2006
Maybe consider running them in parallel as the others have suggested, so make the subs a mono channel and run them from the bridged output of the amp.

Also, take into consideration that the new speakers might not behave as the old ones did in that cabinet, given that it may have been tuned to work well with the old drivers.
  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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
A pondering question on subs skooter Car Audio 16 27th September 2008 07:01 PM
Everything but the subs (simple newb question) bigron Car Audio 10 19th December 2007 07:09 AM
Should I build a home subwoofer system with two 15" MTX Black Golds (car subs)? dan50 Subwoofers 1 13th September 2007 02:47 AM
question for those using subs with 2 channel stereo Jim85IROC Subwoofers 15 26th March 2004 02:38 PM

New To Site? Need Help?

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

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2