# Does lower Ohm mean more distortion?



## Phil Indeblanc (May 27, 2015)

I have always related these 2. Lower the ohm the harder the amp is working and the more distortion rises. Efficiency of the speaker in higher ohm, but how does the amp relate running in lower ohm.

What is acceptable in a car for SQ? WHat level will the ear pick up?
What numbers, like Dampening Factor, or THD level will help us know if an amp running at 2 ohm is feeding mids and highs distortion.

I don't plan to run my front highs and mids at 2ohm, but I have in the past, but I would like to learn a bit more how this works if anyone has some insight.


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## Victor_inox (Apr 27, 2012)

very similar thread popped up a month or so ago, look it up.


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## sirbOOm (Jan 24, 2013)

I shoot for 4-ohms total all around and call it a day. Cuz it's my birthday.


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## Victor_inox (Apr 27, 2012)

sirbOOm said:


> I shoot for 4-ohms total all around and call it a day. Cuz it's my birthday.


Surprize!:laugh::rimshot::rimshot::beerchug:epper:


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## Phil Indeblanc (May 27, 2015)

I did look it up for the first couple pages, and thought I'd post...but yes, I should work the search feature.
thnx


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## SkizeR (Apr 19, 2011)

2 ways to answer that question. the black and white way, yes it does. the other way, no you wont be able to hear the difference. pretty much all modern amps that are true to their specs will be fine. dont worry about damping factor and thd. theyre pretty much irrelevant in a car environment.


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## Phil Indeblanc (May 27, 2015)

thanks Skizer....All this time I was searching and I couldnt find that thread . I even lowered my search criteria to just "ohm"  maybe a link would have helped?

I did stumble upon interesting reads,


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## SkizeR (Apr 19, 2011)

is he talking about the thread started by gstokes?

maybe this?

http://www.diymobileaudio.com/forum...745-interesting-facts-about-dvc-speakers.html


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## Phil Indeblanc (May 27, 2015)

The link will help as Im looking for some more depth understanding of it.
thanks


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## SkizeR (Apr 19, 2011)

Phil Indeblanc said:


> The link will help as Im looking for some more depth understanding of it.
> thanks


there was nothing useful in it anyway. here are some much better links to someone with a lot of experience and respect in the industry.

http://www.bcae1.com/thd.htm

http://www.bcae1.com/dampfact.htm


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## Phil Indeblanc (May 27, 2015)

No, I didn't find much in the first one.
I was looking more for how they effect mids highs. Often I hear installers say to ditch the rear seats doors, and use the rear amp channels to double up on the fronts. And I've always thought that maybe quality is the cost of the power increase


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## gstokes (Apr 20, 2014)

Phil Indeblanc said:


> I have always related these 2. Lower the ohm the harder the amp is working and the more distortion rises. Efficiency of the speaker in higher ohm, but how does the amp relate running in lower ohm.
> 
> What is acceptable in a car for SQ? WHat level will the ear pick up?
> What numbers, like Dampening Factor, or THD level will help us know if an amp running at 2 ohm is feeding mids and highs distortion.


In the olden days the primary reason for driving speakers (primarily subwoofers) at a lower impedance was to increase damping factor, this was before the advent of modern amplifiers and is no longer an issue..
Lower impedance does not equate to increased distortion..


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## SkizeR (Apr 19, 2011)

gstokes said:


> In the olden days the primary reason for driving speakers (primarily subwoofers) at a lower impedance was to increase damping factor


no it wasnt. it was to get the most power out of their system since power wasnt as cheap as it is today. why do you think companies like orion made their amps stable to under 1 ohm and then some. plus, lower impedence equals lower damping factor. how do you not know this after posting a thread about it only a couple weeks ago?




gstokes said:


> Lower impedance does not equate to increased distortion..


technically yes it does, itll double, just like damping factor will be halved. but its not audible


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## gstokes (Apr 20, 2014)

SkizeR said:


> no it wasnt. it was to get the most power out of their system since power wasnt as cheap as it is today. why do you think companies like orion made their amps stable to under 1 ohm and then some. plus, lower impedence equals lower damping factor. how do you not know this after posting a thread about it only a couple weeks ago?
> 
> technically yes it does, itll double, just like damping factor will be halved. but its not audible


i saw where you reposted a link i supplied then in the very next sentence stated there was nothing useful in it, if that's the case then why did you repost it Skizer..

now you say there is distortion but it's not audible  
technically speaking, you are FOS..


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## SkizeR (Apr 19, 2011)

gstokes said:


> i saw where you reposted a link i supplied then in the very next sentence stated there was nothing useful in it, if that's the case then why did you repost it Skizer..
> 
> now you say there is distortion but it's not audible
> technically speaking, you are FOS..


i dont get it, your saying im full of **** because i said the doubling of an extremely minuscule amount of distortion will not have an audible difference?


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## SkizeR (Apr 19, 2011)

reading it again you seem to think that any amount of distortion is audible. is this the case? do you truly believe that you will hear a difference between .01%, .05%, or even .1% distortion? if so, donate your body to science asap


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## Phil Indeblanc (May 27, 2015)

I think that level of distortion being audible is more market driven, since we see the readings at .01, .05%, so I don't know when distortion sounds audible! but getting the least at rated levels is always a good starting point if SQ is the overall main concern....I would think, or at least we are trained to think.


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## SkizeR (Apr 19, 2011)

Phil Indeblanc said:


> I think that level of distortion being audible is more market driven, since we see the readings at .01, .05%, so I don't know when distortion sounds audible! but getting the least at rated levels is always a good starting point if SQ is the overall main concern....I would think, or at least we are trained to think.


according to this experiment, to detect anything over 10% distortion the frequency had to be over 500 Hz, distortion in 8khz test tones are at 1% distortion., 

Experimental Study : Distortion - Axiom Audio



there are some test tracks that have various distortion levels that you can test yourself


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## Phil Indeblanc (May 27, 2015)

So according to that link.... we can hear distortions at about 3% in the higher frequencies, which is consistant with what I said above regarding mids and particularly highs.

Some listeners maybe more sensitive, and some less, so I still put weight on the THD % that brands state. I will look for the least possible. But how they make the claims on the box labels would also be interesting. !% sound perfectly fine by some standards, but what those standards are maybe interesting to know.


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## cajunner (Apr 13, 2007)

are you that bored that you have to make up stuff to argue about?

lower ohms is relative. Some amps were designed to run in a low impedance condition, and some can run low but are biased to run at 4 ohms.

the Japanese variety of amps were almost always biased for 4 ohm but could run 2 ohm, and yes, distortion does increase when you halve the resistance, but driving small motors equals lower amounts of back EMF from the speaker, and those Japs like their vocals. The big craze with several pairs of woofers on an amp, is mostly an American origin, the reason that happened is a natural outcropping of the music scene and the discovery of cabin gain, allowing bigger motors to force air pressure inside closed chambers.

I bought Bass Mechanik, when it first came out.

The problem with driving so many woofers relates to damping factor, as the more control the amp had over the compounded back EMF, the better it would sound at it's limits.

that was how they sold US Amps, it was similar to the claim by Rockford that through Power Cube testing they had the superior circuit, reactive loads vs. damping factor.

Bose makes amps that are supposed to run at .5 ohm, it doesn't mean it's a superior amp though.

It takes advantage of the 12V supply to produce more power without having to create high voltage rails using a transformer, it's just that you don't see very many high-test, or audiophile speakers that have a .5 nominal rating.

The specs for amps can be quite varied, from the prototype to the production run, and when you look at various birth sheets you can see quite a bit of spread from higher to lower power.

also, realize that an amp that says "stable to 2 ohms" is really not meant to drive 2 ohm speakers. It means that if a 4 ohm rated speaker has a dip in it's impedance curve that drops to 2 ohms the amp can handle it.

The same thing is true for amps that are "stable to 1 ohm," they are also supposed to be driving 2 ohm loads, and have a cushion that says if the speaker that is 2 ohm rated does have a dip, it can handle it...

now I know a lot of people put their 1 ohm loads on their 1 ohm stable amps, and run them all the time without any issues.

it's just that doing so, is not what the manufacturer recommends unless the amp is a cheater that is designed for much lower impedance levels and fudged the spec sheet for the competitor, who used to enter competition based on 4 ohm ratings.

I would forget about the amount of sound degradation that occurs with lower ohm loads. I would remember about durability, longevity, and reliability.

Also, since you are sucking huge amounts of inefficient current through an AB class amp when you drop the impedance of the load, the car itself will have an opportunity to contribute to "more distortion" because once you tax the electrical supply it will just dump huge current to maintain the rails, which is compounded when the voltage sags.

The lower the system voltage, the more the amp has to pull current. The more current that is pulled through the amp, the greater the chance of something going bad, you will find an amp that has a normally compensated malfunction or near out of tolerance part with normal loads, just die when hit with the low impedance.

as far as whether it's really noticeable when a strong, well built amp goes from 4 ohms to 2 ohms in terms of distortion, noise, or frequency response changes, that's usually not anything to concern yourself with, in a relative sense.


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## Phil Indeblanc (May 27, 2015)

All understood and makes sense. 

I was asking for the sake of discussion, and better understanding.


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## Mitsushi (Jul 29, 2015)

Lower ohm usualy is not that precise sound... when it higher ohmage it gives a clearer sound on the speakers


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## hakmazter (Jul 19, 2013)

Damping factor matters way more than you think. I used to intentionally run 8 ohm drivers in stereo when I competed back in the day off HCCA amps, but they had a 130dB cap. My car would do 131-132dB.

Damping factor is how the amp controls the speaker. Play Metallica One at different impedences and get back to me about how the guitar and drum sound at the same time.


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## gijoe (Mar 25, 2008)

hakmazter said:


> Damping factor matters way more than you think. I used to intentionally run 8 ohm drivers in stereo when I competed back in the day off HCCA amps, but they had a 130dB cap. My car would do 131-132dB.
> 
> Damping factor is how the amp controls the speaker. Play Metallica One at different impedences and get back to me about how the guitar and drum sound at the same time.


Are you serious?


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## Dynamic SQ (Jul 25, 2015)

sirbOOm said:


> I shoot for 4-ohms total all around and call it a day. Cuz it's my birthday.


I'm with you, and it's not even my birthday.

Every time you halve your load, all specs basically get 2 times worse. Some say they can't tell a difference, some say they can. 

I like going 4 ohm all around. Even on subs (8 ohm bridged). I'll take any gain I can get. Plus, your basically putting your amps on cruise control. Headroom for days, cooler amps, and better specs. What more can you ask for??


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## Victor_inox (Apr 27, 2012)

I`ll always take higher damping factor over 50% increase in power.


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## KSakai (Jul 31, 2015)

long run cable can also reduce the total DF of an amplifier..

for distortion, yes they do increase as the load resistance lowered..


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## Hillbilly SQ (Jan 26, 2007)

KSakai said:


> long run cable can also reduce the total DF of an amplifier..
> 
> for distortion, yes they do increase as the load resistance lowered..


Say what?  I do know that with lower impedance you need larger gauge speakerwire for whatever reason according to bcae1. Hell I just shoot for 4 ohm per channel or 8 ohm bridged just for good measure. And never run a class d subwoofer amp below 2 ohms even if it will run at 1 ohm full tilt all day every day.


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