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

Can you use a 8 ohm crossover with 4 ohm speaker?
Can you use a 8 ohm crossover with 4 ohm speaker?
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 19th May 2005, 08:33 PM   #1
Bull is offline Bull  United Kingdom
diyAudio Member
Join Date: Oct 2002
Location: ...........
Question Can you use a 8 ohm crossover with 4 ohm speaker?

That 18 inch driver I showed you guys earlier[The RCF in the twin slot vented Martin Audio enclosure] sounds pretty nice but mid frequencies are coming through and making it sound crap.Box is tuned to 30hz and says that on the back under the Martin Audio writing on the back panel.

So I'm gonna use a passive crossover[passive low pass filter] cut off at no more than 120hz. But the problem is the driver is 4 ohm, and the passive low pass filter I wish to use is rated 8 ohms.

So will an 8 ohm passive low pass filter cope with a 4 ohm bass speaker without sounding horribly wrong and will it turn the 4 ohms into 8 ohm load???

Gonna be powering it with one channel of a QSC RMX2450 [750w rms into 4 ohm] if the passive LPF doesn't change the impedance.
If the passive LPF changes the 4 ohm driver to 8 ohm of what the filter is rated at then I'll use the sub in bridge mode giving it 1500w rms into 8 ohms.

RCF driver is rated 700w rms and is gonna be my sub for disco use.
  Reply With Quote
Old 19th May 2005, 08:37 PM   #2
richie00boy is offline richie00boy  United Kingdom
Did it Himself
diyAudio Member
richie00boy's Avatar
Join Date: Nov 2003
Location: Gloucestershire, England, UK
Can you use a 8 ohm crossover with 4 ohm speaker?
It's not that the filter will not be able to 'take' the 'reduced load' or that it will change the impedance (it won't as such), merely that the intended -3dB frequency will double.

As you are giving the driver it's own amp channel you will get massively better result with a simple active filter in front of the amp. Passive crossovers and subs are just a recipe for old pants.
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, modules and more.
  Reply With Quote


Can you use a 8 ohm crossover with 4 ohm speaker?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
speaker or crossover damage evlah Multi-Way 9 19th March 2008 03:49 PM
speaker crossover/amp broken djradiorick Multi-Way 0 30th September 2007 08:09 PM
Crossover at speaker level? icebear Multi-Way 0 23rd November 2005 12:52 PM
Help for Crossover Designing for 3 way speaker CH2 Multi-Way 16 9th April 2004 04:01 PM
Can you hear the crossover point of a speaker with a well-designed crossover? 454Casull Multi-Way 11 2nd April 2004 05:48 AM

New To Site? Need Help?

All times are GMT. The time now is 11:40 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio