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nick_19

distortion--what exactly is it?

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Without having to delve too deep into the world of signal reproduction and the discrepancies in what the human ear perceives, can someone please simply explain distortion, how it relates to us simple "daily system" people, and the relevance/relativity in terms of overall distortion of "-40 dB from the fundamental."

I read this article, and I understand the basic concepts presented, but I was wondering if anyone could put it in more of Laymen's terms. Thanks!

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Completely different thread. I did not mention that particular product one time. Please do not turn this into something nobody will learn from. Keep it on topic. If you have nothing to say that will further everyone's knowledge on the subject at hand, then please sit back and eat your popcorn.

In essence, does this distortion come primarily from overdriving amplifiers/sound processors/head units or is it inherent in large amounts in any audio system? Is it merely unpleasant to listen to or can it be damaging to the speaker itself?

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No need to have your panties in a bunch over my comment.

All it meant was I'm eager to see what somebody posts. I didn't mean this would turn into a shit thread. Even though it might if people, who don't understand the topic but tries to prove they do.

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heat?

heat is always a loss

square wave?

boom?

lol

while i was writing this i was thinking i made some dubstep song yesterday and added in alot of distortion to the sound.

does this mean when its reproduced, its reproduced as distortion?

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heat?

heat is always a loss

square wave?

boom?

lol

while i was writing this i was thinking i made some dubstep song yesterday and added in alot of distortion to the sound.

does this mean when its reproduced, its reproduced as distortion?

In a perfect world, yes. Your music SHOULD come out EXACTLY the way it is put in, just amplified. But since that wouldn't sound good to most people you have different ways to alter or color the sound (if you've ever heard that before) to make it sound like you want to. Equalizers, bass boost, even high and low pass filters all affect the sound and take it away from the raw fomat that it is (being an mp3, cd recording, or even a record.) and change it.

What does this have to do with distortion? Well...not all distortion can be heard, and not all distortion is bad. What some people refer to as "warmth" is sometimes distortion. (Disclamier, anything after this could be totally wrong I'm not sure.) From what I understand, Clipping is only a FORM of distorion. Not ALL distorion is clipping.

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I was thinking the same thing, Clipping is a form of distortion, but it doesn't have to be clipped to be distorted.

But I'm not a 100%. And I'm not claiming to be. I wasn't going to post anything until somebody said that same thing.

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I was thinking the same thing, Clipping is a form of distortion, but it doesn't have to be clipped to be distorted.

But I'm not a 100%. And I'm not claiming to be. I wasn't going to post anything until somebody said that same thing.

I'm pretty sure because you can have a crappy mp3 that's distored all to hell but never clips. Or a very clean mp3 that's all dynamic n shiz and clips at a certain point. I have songs that do both.

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Distortion, by definition, is any change in the output that makes it different from the source, in the simplest of terms.

It doesn't have to be clipping, induced noise from nearby electronics, bad input or output devices and components can cause it. Basically anything OTHER than a change in amplitude would fall under the definition of distortion, again in the simplest of terms.

That's always been my understanding of it, after 6 years of electronics classes I hope that's right. LOL. :roflmao::suicide-santa:

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Distortion, by definition, is any change in the output that makes it different from the source, in the simplest of terms.

It doesn't have to be clipping, induced noise from nearby electronics, bad input or output devices and components can cause it. Basically anything OTHER than a change in amplitude would fall under the definition of distortion, again in the simplest of terms.

That's always been my understanding of it, after 6 years of electronics classes I hope that's right. LOL. :roflmao::suicide-santa:

I am gonna side with you on this one and not elaborate anymore since I think this is a good basic explanation.

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jbl 1200.1 == Distortion lol.

Funny how they depict sound as having color or being bright, which i have heard of also why different materials are used. titanium, aluminum, plastic tweeters. metal tweeters are supposed to have a bright sound. yea im not an SQ guy so not a big deal.

So if i put a magnet next to my computer or tv screen that would be distortion would it not?

If i run my Rca's next to my power wire or have a ground loop whine, distortion?

Theres also tire distortion,

During cornering, tire distortion makes a vehicle move at an angle to the direction of the wheels, called slip angle. Cornering force returns the tire to normal position. As cornering force increases, so does slip angle.

carzy distortion

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jbl 1200.1 == Distortion lol.

Funny how they depict sound as having color or being bright, which i have heard of also why different materials are used. titanium, aluminum, plastic tweeters. metal tweeters are supposed to have a bright sound. yea im not an SQ guy so not a big deal.

So if i put a magnet next to my computer or tv screen that would be distortion would it not?

If i run my Rca's next to my power wire or have a ground loop whine, distortion?

Theres also tire distortion,

During cornering, tire distortion makes a vehicle move at an angle to the direction of the wheels, called slip angle. Cornering force returns the tire to normal position. As cornering force increases, so does slip angle.

carzy distortion

I say that's a myth.

That's like saying only a 18inch can reproduce low bass but is also not fast enough for double kick bass.

Its hard to compare a metal dome vs a silk because of the variables. Even a simple swap out, doesn't determine either way.

Or hearing a metal dome in your friends car and you have a silk, its two totally different installs. Way to many variables to even think of comparing.

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I would like impious to come and answer this.

Good answer Alton. Seems very reasonable.

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Distortion is anything other than the original signal. It is as simple as that. The biggest forms of distortion in car audio come from overdriven amplification stages (clipping) frequency shaping (Eq) thermal noise (hiss) RFI/EMI (ignition noise) and AC components getting in the signal chain (alternator whine). This is not an inclusive list, and not in order.

The "-40db" you ask about is pretty simple. db is a logarithmic scale. 40db is roughly 10,000 to 1 as a ratio. Put into simple terms, if you had an amplifier that was putting out 10,000 watts and it had a distortion content of -40db or lower it would be putting out 1 watt or less of distortion at full output. -40db is very low, you would never hear this in a car. Most, and I say most because I mean the average guy banging down the street, probably wouldn't notice anything under -20 or so below the fundemental....

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Without having to delve too deep into the world of signal reproduction and the discrepancies in what the human ear perceives, can someone please simply explain distortion, how it relates to us simple "daily system" people, and the relevance/relativity in terms of overall distortion of "-40 dB from the fundamental."

I read this article, and I understand the basic concepts presented, but I was wondering if anyone could put it in more of Laymen's terms. Thanks!

Your question(s) are pretty open ended. I guess I wouldn't even really know where to start as I don't know which part you didn't particularly understand, and I thought that article did a pretty good job of explaining it in relatively simple terms. Could you narrow down your confusion some?

Distortion, as explained above, is any deviation from the original signal (other than the intended increase in amplitude). The largest distortion generator in a system is the speakers.

Though I can take a stab at the daily system part......it seems most people can't hear distortion, or atleast find excessive amounts of it acceptable :P Seriously though, how offensive distortion is depends on a huge amount of factors. Frequency, level of the various harmonics, masking effects of the music, duration of the signal, etc etc. Basically, distortion is "easy" to hear if you listen to pure tones but much more difficult to notice depending on the various other factors involved. Generally even order harmonics are less offensive than odd order harmonics, and the higher the order of the harmonics the more offensive they are.

The "-40db down from the fundamental" is an expression of the level of the particular distortion component compared to the level of the fundamental. If a 50hz tone is played, it will generate harmonic distortion at 100hz (2nd harmonic), 150hz (third harmonic), 200hz (forth harmonic), so on and so forth. So if the 2nd harmonic (100hz) is -40db down from the fundamental, then it is 40db lower in volume than the fundamental.....or, the 2nd fundamental is at an approximately 1% distortion level.

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Thank you all for the responses!

I guess what I was trying to ask is this: for the average guy, why would distortion matter if (as 95Honda's example stated) only 1 out of 10k watts was distortion? I would safely venture that I personally would never be able to hear that. How could it damage my subwoofer or speakers? What would be the purpose of limiting distortion besides making the sounds more "pure?" Does distortion coming directly from an amplifier or head unit display that it is playing beyond it's full potential?

Thanks you so much. Just tell me if I'm still being too vague.

This is how I am seeing it right now:

-too much power is the only thing that kills speakers

-by measuring distortion from an isolated source (i.e. Head unit, amp) one can see where it begins to clip (causing distortion)

-this clipping indicates that the device has reached it's limit to produce power

-by finding this limit, one knows APPROXIMATELY where the device will put out it's rated (and proper for the application) amount of power

-this enables one to set gains, EQ, etc. to its "full potential" without overburdening it or overpowering the speaker

....maybe?

Edited by nick_19

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Not really necessary. What do you gain by setting your system at a level that is under an amount that you can hear? How are you compensating for different recording levels on CD's? Max non-clipped output power isn't a determining factor in what your speakers can survive. They have a level of Average power they can take and you can't exceed that. Depending on the size of your amplifier that could easily be even a fully clipped signal. How then is it beneficial to measure/set gains based on some nonsensical level that is determined incorrectly by some harmonic at -40dB?

If you are wondering on my last sentence, pretty easy to figure out. If you want to measure THD (total harmonic distortion) and want it to be at -40dB or less, how you would design an analog circuit to do that? That's right you'd make a detector for each and every harmonic and then a summing circuit. Obviously a very strange way to do this when you could much more easily do this in the digital domain.

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Not really necessary. What do you gain by setting your system at a level that is under an amount that you can hear? How are you compensating for different recording levels on CD's? Max non-clipped output power isn't a determining factor in what your speakers can survive. They have a level of Average power they can take and you can't exceed that. Depending on the size of your amplifier that could easily be even a fully clipped signal. How then is it beneficial to measure/set gains based on some nonsensical level that is determined incorrectly by some harmonic at -40dB?

If you are wondering on my last sentence, pretty easy to figure out. If you want to measure THD (total harmonic distortion) and want it to be at -40dB or less, how you would design an analog circuit to do that? That's right you'd make a detector for each and every harmonic and then a summing circuit. Obviously a very strange way to do this when you could much more easily do this in the digital domain.

I really don't want to seem like an idiot but....how? I'm not really following...I understand the first paragraph fully if that means anything.

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Not really necessary. What do you gain by setting your system at a level that is under an amount that you can hear? How are you compensating for different recording levels on CD's? Max non-clipped output power isn't a determining factor in what your speakers can survive. They have a level of Average power they can take and you can't exceed that. Depending on the size of your amplifier that could easily be even a fully clipped signal. How then is it beneficial to measure/set gains based on some nonsensical level that is determined incorrectly by some harmonic at -40dB?

If you are wondering on my last sentence, pretty easy to figure out. If you want to measure THD (total harmonic distortion) and want it to be at -40dB or less, how you would design an analog circuit to do that? That's right you'd make a detector for each and every harmonic and then a summing circuit. Obviously a very strange way to do this when you could much more easily do this in the digital domain.

I really don't want to seem like an idiot but....how? I'm not really following...I understand the first paragraph fully if that means anything.

An analog filter requires a dedicated circuit for every frequency. In the case of measuring the THD this means that you need a circuit for each and every harmonic to measure THD. Then some method of summing it. A standard digital microprocessor can have this running on it and do the calculation on the fly. Much more efficient way of implementing the algorithm.

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Im sorry i get stuck straing at nicks avi and the fact he now has 666 post, lol

OT :ohnoes9:

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