1 ohm sq?

[roadshop3 10+ year member]

i plan on getting 2 polk sr124 they are dvc at 4 ohms, and powering it by the mtx te1501d. it puts out 1500rms at 1 ohm so it would power those polks perfect. i'm going for sq and is the reason im going with the polks.

My Question: does ohm load effect sound quality?

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i plan on getting 2 polk sr124 they are dvc at 4 ohms, and powering it by the mtx te1501d. it puts out 1500rms at 1 ohm so it would power those polks perfect. i'm going for sq and is the reason im going with the polks. My Question: does ohm load effect sound quality?

thanks!//content.invisioncic.com/y282845/emoticons/yumyum.gif.0556df42231b304b9c995aefd13928a8.gif

No

 

[regal8r 5,000+ posts]

i plan on getting 2 polk sr124 they are dvc at 4 ohms, and powering it by the mtx te1501d. it puts out 1500rms at 1 ohm so it would power those polks perfect. i'm going for sq and is the reason im going with the polks. My Question: does ohm load effect sound quality?

thanks!//content.invisioncic.com/y282845/emoticons/yumyum.gif.0556df42231b304b9c995aefd13928a8.gif

lower ohm loads tend to increase the THD percentage of the amp at that ohm

 

[Prowler573 5,000+ posts]

lower ohm loads tend to increase the THD percentage of the amp at that ohm

But if we're talking about a decent-quality amp as well as an amp that is intended for substage usage the percentage of THD increase is still negligible and to almost all human ears, inaudible.

 

[roadshop3 10+ year member]

from what i understand that amp is pretty good, correct?

 

[regal8r 5,000+ posts]

But if we're talking about a decent-quality amp as well as an amp that is intended for substage usage the percentage of THD increase is still negligible and to almost all human ears, inaudible.

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i wasnt sure if he was asking if there would be any difference at all, which there WILL be, but like you said, any difference isnt going to be detectable by human ear

 

[Twistid 5,000+ posts]

from what i understand that amp is pretty good, correct?

its a current hog

 

[roadshop3 10+ year member]

im running a 1.2 cap, and zero gauge. do u think all be alright?

its in a 98 c class, the battery is giant

 

[Prowler573 5,000+ posts]

I think the 'stiffening' cap was a wasted expenditure.

I also think you'd be well advised for us to suggest upgrading the "Big 3" of underhood wiring. For more info on that topic see this thread.

 

[envengineer 10+ year member]

Compared to the distortion inherant to most subwoofers (many over 20%), nearly any reasonable amount of amplifier distortion will be insignificant.

 

[JonJT 10+ year member]

The added distortion produced by the amp is neglible in comparison to the change in responce of the driver. Changing the wiring of teh voice coils can have a drastic effect on the performance of the woofer. A 1 ohm setup for the woofer I want really upsets the performance to a point where I'd consider a different driver.

You should play around with different alignments in unibox to see what effect your desired setup will have.

 

[bigbang 10+ year member]

Doesn't the dampening factor of the amp's control over the woofer go down as you reduce the ohm's? Is this why distortion increases? Somebody explain this to me, I've wondered about this.

 

[audioholic 5,000+ posts]

Compared to the distortion inherant to most subwoofers (many over 20%), nearly any reasonable amount of amplifier distortion will be insignificant.

20% of what?//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

 

[envengineer 10+ year member]

20% of what?//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

THD always refers to the level of distortion relative to the level of the reproduction of the original signal. It is the sum of the even and odd harmonic distortion values along with intermodulation distortion.

So when I said 20%, I meant that many subs produce distortion levels that are 20% as strong as the original signal. npdang has a very good explanation over at DIYMA, far better than my attempt at explaining it.

Take a look at the Aura ns12 review here http://www.diymobileaudio.com/forum/showthread.php?t=11335 and the Atlas vs. TC2 review here http://www.diymobileaudio.com/forum/showthread.php?t=8 . You can see the distortion is quite high. On the distortion analysis plot you can see three distortion figures (BL, suspension, and inductance)

The reason nobody really cares is because it is almost inaudible due to the harmonics being so close. At 20 hz you've got distortion at 40 hz, 60 hz, etc. and at only 20% of the original volume, the distortion is virtually indistinguishable from the original signal to the human ear.

In a tweeter on the other hand, the distortion products are very audible. Say you play a test tone at 5 khz. You've got harmonics at 10 khz, 15 khz etc. Those are all very distinguishable. If you want to hear 5 khz, you are definitely going to notice a 15 khz tone being reproduced as a result of distortion, even if it is a relatively low percentage.

To help better clarify, take a look at this velodyne link http://www.velodyne.com/velodyne/tech/faqanswer.aspx?ID=12&sid=316d224n they give a target of 10% as being very good for a subwoofer. I just kind of pulled that link out of my *** by doing a google search but it helps make my point.

 

[audioholic 5,000+ posts]

I know what THD is, I was simply asking what you were referring to, as you didnt specifiy.

IMO any reasonable sub that is kept within its xmax will not produce anywhere near 20% distortion vs THD. Furthermore, many 'BL optimized' drivers today are capable of producing virtually inaudible distortion up until they reach their xmax limits. At that point, signal distortion is [almost] everything.

The key to your initial comment was any amplifier with a 'reasonable' amount of distortion. The same could be said of any subwoofer with a reasonable amount of distortion present. Either component, speaker or amplifier (or any other device in the signal chain) are capable of producing unacceptable levels of distortion, given an unacceptable working condition.

Cheers. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif