CarAudioForum.com

Go Back   CarAudioForum.com > Discussion Forums > Car Audio: General

Reply
Old 03-23-2011, 12:41 AM   #1
lyledperry

Registered User
 
Join Date: Mar 2011
Posts: 35
lyledperry is on a distinguished road



Can you run 2 ohm speakers of head unit?

Hey,

So I have been reading up on this all day. The opinions are varied.
I have a Pioneer DEH P3000IB head unit (50 x 4 peak and 22 x 4 RMS).

Would I be able to run front 2 (or even all 4) speakers which are rates at 2ohms? Am specifically looking at Inifnity Kappa 652.9i 6.5" speakers which are rated at 2 ohm or maybe Polk audio MM651 6.5" speakers which are ratede at 2.76 ohm.

My HU manual says
Maximum power output ....... 50 W 4
50 W 2/4 OHM + 70 W 1/2 OHM (for subwoofer)
Continuous power output ... 22 W 4 (50 Hz to 15 000
Hz, 5% THD, 4 OHM load, both channels driven)
Load impedance ...................... 4 OHM to 8 OHM 4
4 OHM to 8 OHM 2 + 2 OHM 1

Now will these speakers connected to my head unit (HU) and no amp, fry the internal amp in my HU? Anyone ever done this??

Last edited by lyledperry; 03-23-2011 at 12:59 AM. Reason: changed the part i copied from my HU manual
lyledperry is offline   Reply With Quote

Sponsored Links
Help Syrian Refugees Survive. Donate Now!
Or text REFUGEES to 50555 to give $10 to USA for UNHCR
Old 03-23-2011, 12:46 AM   #2
HuckOrris

Registered User
 
Join Date: Mar 2009
Location: The Real Nor-Cal
Posts: 1,559
HuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond repute



That's not a good idea. All head unit amps that I know of need a minimum of 4 ohms impedance. Anything lower leads to various problems.

Quote:
"Load impedance ...................... 4 W to 8 W 4
4 W to 8 W 2 + 2 W 1"
That doesn't really make sense.
HuckOrris is offline   Reply With Quote

Old 03-23-2011, 12:47 AM   #3
99chevy7.4L

Registered User
 
Join Date: Sep 2010
Location: Bama
Posts: 247
99chevy7.4L is just really nice99chevy7.4L is just really nice99chevy7.4L is just really nice99chevy7.4L is just really nice



It depends on the specs of the amp in the head unit. I have not seen a head unit whose amplifiers will handle a 2 ohm load.
99chevy7.4L is offline   Reply With Quote

Old 03-23-2011, 12:52 AM   #4
lyledperry

Registered User
 
Join Date: Mar 2011
Posts: 35
lyledperry is on a distinguished road



Quote:
Originally Posted by HuckOrris View Post
That's not a good idea. All head unit amps that I know of need a minimum of 4 ohms impedance. Anything lower leads to various problems.

That doesn't really make sense.
Sorry the ohm sign didn't come out and printed as a W??? This is what is says:
Audio:
Maximum power output ....... 50 W 4
50 W 2/4 OHM + 70 W 1/2 OHM (for subwoofer)
Continuous power output ... 22 W 4 (50 Hz to 15 000
Hz, 5% THD, 4 OHM load, both channels driven)
Load impedance ...................... 4 OHM to 8 OHM 4
4 OHM to 8 OHM 2 + 2 OHM 1

Does that make any sense??
lyledperry is offline   Reply With Quote

Old 03-23-2011, 01:28 AM   #5
basicxj

Registered Spam Offender
 
Join Date: Jul 2006
Location: north of the 49th
Posts: 14,532
basicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond repute



Infinity says 2 ohm loads are fine for head units, but there have been a number of people over the years who have done that and had their head unit's internal amplifiers spontaneously power down (becoming unstable) with a 2 ohm load. I would never recommend it.

If it is any consolation, Infinity speakers typically suck- if you don't care about midbass and like the high frequency response to be ear piercing and bordering on screechy sounding, Infinity Kappas may be for you. If you think I'm bashing for no reason, I used to own Infinity speakers (and couldn't wait to replace them fast enough). Punch "Infinity" into the forum's search function for more personal opinions on the brand- enable "show older posts" under your user settings.
basicxj is online now   Reply With Quote

Old 03-23-2011, 02:20 AM   #6
HuckOrris

Registered User
 
Join Date: Mar 2009
Location: The Real Nor-Cal
Posts: 1,559
HuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond reputeHuckOrris has a reputation beyond repute



I tried responding a few hours ago but my connection messed up just as I was submitting. arg.

It looks like the hu is spec'ed to only run one 2 ohm channel for a sub lol.

It doesn't say it can run 2 ohm with 2 channels.

Just try getting some efficient speakers to make the most of what little power is available.
HuckOrris is offline   Reply With Quote

Old 03-23-2011, 05:15 PM   #7
lyledperry

Registered User
 
Join Date: Mar 2011
Posts: 35
lyledperry is on a distinguished road



Yeah that's what I thought those specs listed meant.

Ok cool, thanks for the input. I am not going to run 2 ohm speakers. Will get some high sensitivity 4 ohm speakers. Have seen some pioneers and Kenwood 6.5" speakers with 92db frequency and a decent freqency response range.

Anyone know of other 4 ohm 6.5" speakers with a higher sensitivity than 92db?? Only the 2 ohm I have found have hihger sensitivity like the Infinity and Polk Audio speakers.

Thanks guys, VERY much appreciated
lyledperry is offline   Reply With Quote

Old 03-23-2011, 09:56 PM   #8
basicxj

Registered Spam Offender
 
Join Date: Jul 2006
Location: north of the 49th
Posts: 14,532
basicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond reputebasicxj has a reputation beyond repute



Quote:
Originally Posted by lyledperry View Post
Yeah that's what I thought those specs listed meant.

Ok cool, thanks for the input. I am not going to run 2 ohm speakers. Will get some high sensitivity 4 ohm speakers. Have seen some pioneers and Kenwood 6.5" speakers with 92db frequency and a decent freqency response range.

Anyone know of other 4 ohm 6.5" speakers with a higher sensitivity than 92db?? Only the 2 ohm I have found have hihger sensitivity like the Infinity and Polk Audio speakers.

Thanks guys, VERY much appreciated
Published sensitivity specs are meaningless as a true indication of in-car performance unless you (like the lab) are using 1 watt of input power and listening from 1 meter away (testing criteria).

Speakers ranging from the 80's to the mid 90's in db with 1 watt/meter are the norm for automotive aftermarket speakers, and good engineering and design combined with matching a speaker up to a good power source (think aftermarket amplifier) are far more important to good performance than an impressively high laboratory efficiency spec that loses meaning when we apply 50-60x that power and listen near field in the car.
basicxj is online now   Reply With Quote

Reply

Bookmarks

Tags
2 ohm, amp, fry, headunit

Thread Tools
Display Modes

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


All times are GMT. The time now is 06:51 PM.
Powered by vBulletin® - Copyright © 2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 1996 - 2011 by CarAudioForum.com - all rights reserved.