The physics and understanding of low frequencies - Page 9 - AVS Forum
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post #241 of 345 Old 03-04-2011, 10:08 AM
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Originally Posted by ymalmsteen887 View Post

Its like everyone is asking trick questions. When you say sawtooth wave frequency you are talking about the pattern it makes before repeating, righ? If yes then that would be its fundemental, There are other frequencies there that if give it that shape on a graph. Basically a sawtooth wave is a combination of frequency intergers at different amplitudes

I wouldnt call a speaker vibrating a wave. But the vibration should be identical when not taking into consideration reflections that have superimposed on the incoming sound.

Irrelevant, in my opinion. You yourself stated that 50Hz sounds like 50Hz. Sphinx asked you the exact same question I was about to, and he is headed in the exact same direction I was going to.

The answer to Sphinx's question is, "No. They do not sound alike," but they do not sound alike because of something entirely different than what I am certain you are thinking.

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post #242 of 345 Old 03-04-2011, 10:12 AM
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Originally Posted by ymalmsteen887 View Post

Whats with the shrug and the parentheses it doesnt matter if there are two different sources playing 50hz they are superimposed in the air and those the ear drum to either make louder or softer and if the room vibrates and makes sounds that is another sound has nothing to do with 50hz. You dont seriously mean that if I play bass in a car and it vibrates the dash that is coloring the sound?

There are SO many factors other than merely an input frequency which affect the actual sound we hear...

There just are.
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post #243 of 345 Old 03-04-2011, 10:20 AM - Thread Starter
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Originally Posted by ccotenj View Post

havent been following along, but yes, vibration most certainly will color the sound.

I cant believe I used the word color. No it doesnt its just another sound I can hear the bass and the rattling. Need to get something to keep it from vibrating. Didnt you read where I said if you play the guitar and someone talks it might the persformance less enjoyable but the sound is unaltered only superimposed.
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post #244 of 345 Old 03-04-2011, 10:24 AM - Thread Starter
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Originally Posted by WheelerM View Post

Irrelevant, in my opinion. You yourself stated that 50Hz sounds like 50Hz. Sphinx asked you the exact same question I was about to, and he is headed in the exact same direction I was going to.

The answer to Sphinx's question is, "No. They do not sound alike," but they do not sound alike because of something entirely different than what I am certain you are thinking.

Then the question is a trick question. I am saying a flucuation of 50 cycles always sounds the same. A saw tooth wave is not just 50cycles its also 100,150,200 etc....
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post #245 of 345 Old 03-04-2011, 10:25 AM - Thread Starter
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Originally Posted by enderland View Post

There are SO many factors other than merely an input frequency which affect the actual sound we hear...

There just are.

I am not denying there are I am just saying that 50hz is 50hz
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post #246 of 345 Old 03-04-2011, 10:28 AM
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So, why doesn't a 50Hz triangle wave sound the same as a 50Hz sine wave?

A better question: can you describe how you think a speaker cone moves when it plays a 50Hz wave, regardless of the waveshape?

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post #247 of 345 Old 03-04-2011, 10:29 AM - Thread Starter
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Originally Posted by KC Sphinx View Post

WRT the speaker.

Let me rephrase another way.

Speaker receives input signal. Speaker cone moves in response to signal.

It is my understanding that the following 3 waves are different.
1. Input signal
2. Cone output
3. Eardrum input

Due to, but not limited to... time delay, inertia, reflections, distortion

And it is further my understanding that the above variables affect every speaker differently and therefore, no two speakers, given the same signal, will 'sound' the same at the ear, regardless of equalization .

I am a true novice of audio, and this i just he gist of what I have picked up in the short time on this forum.

Well besides the input signal and cone output once the air starts vibrating and your ear are vibrating those factors are already taken into consideration since that never changes and if your brain responds to higher frequecnies more for example then those factors would already be put into the math since only humans listen to speakers.
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post #248 of 345 Old 03-04-2011, 10:30 AM
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Originally Posted by ymalmsteen887 View Post

Didnt you read where I said if you play the guitar and someone talks it might the persformance less enjoyable but the sound is unaltered only superimposed.

I think a disconnect between many on here is how you are using 'sound'.

I think, most, here interpret 'sound' as the sum of what you hear.

Are you using 'sound' to describe only the guitar's portion of the sound?

When many say it "colors" the sounds, they mean it changes the sum of what you are hearing.
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post #249 of 345 Old 03-04-2011, 10:32 AM
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I don't really understand your reply. Wouldn't room reflections/absorptions affect what air arrives at my ear.

Can't my dog listen to the speaker also? I know she goes crazy if there is a dog bark during a movie/tv, lol.
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post #250 of 345 Old 03-04-2011, 10:32 AM - Thread Starter
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Originally Posted by WheelerM View Post

So, why doesn't a 50Hz triangle wave sound the same as a 50Hz sine wave?

A better question: can you describe how you think a speaker cone moves when it plays a 50Hz wave, regardless of the waveshape?

You keep saying shape can you post a picture of a triangle wave so we can analyze it.

About the other question if you turn a waveform on its side and play it the speaker cone would be moving in and out in accordence with the wave. Basically all speakers do is vibrate back and forth. However musical instruments do something more complex than this but their interaction with the air and your eardrum is the same principle.
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post #251 of 345 Old 03-04-2011, 10:35 AM - Thread Starter
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Originally Posted by KC Sphinx View Post

I think a disconnect between many on here is how you are using 'sound'.

I think, most, here interpret 'sound' as the sum of what you hear.

Are you using 'sound' to describe only the guitar's portion of the sound?

When many say it "colors" the sounds, they mean it changes the sum of what you are hearing.

Thats fair I was saying when a guitar vibrates the ear on the way to your ear a person is talking close to you and vibrating the air as well but on the way to your ear that dont knock each other way they superimpose but the brain can distingush the guitars intergers and their phase to make a coherent sound regardless is someone is talking or making a bunch of noise so long as the noise isnt much louder than the guitar that is.
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post #252 of 345 Old 03-04-2011, 10:36 AM - Thread Starter
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Originally Posted by KC Sphinx View Post

I don't really understand your reply. Wouldn't room reflections/absorptions affect what air arrives at my ear.

Can't my dog listen to the speaker also? I know she goes crazy if there is a dog bark during a movie/tv, lol.

Yeah but we arent adjusting EQ for the dogs preferences
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post #253 of 345 Old 03-04-2011, 10:40 AM
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There you go.

With respect to your explanation regarding speaker movement, are you saying that the speaker only moves in and out and that's it?

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post #254 of 345 Old 03-04-2011, 10:51 AM
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Quote:
Originally Posted by ymalmsteen887 View Post

Also What exactly is a flat frequency repsonse? I know it mean that all frequencies will play the same volume but music is never one volume and alot of times some instruments are louder than others. The only way having speakers and wquilizers ideal is if there is some kind of standard to recording music and other sounds so that the playback is always equal to another. In other words the only thing sounding bad is your speakers and/or equipment but you can't blame it on the recording. This does not seem to be the case though. I have heard plenty of kickdrum hits from different bands/recordings that are easier to hear without alot of bass you hear this high pitch slap even on a cell phone when there is double bass I am guessing the upper harmonics of the drum but some recordings you can't hear this unless the kickdrum is the only sound present, unless its the kickdums themselves that have these differences and not the eq of the recording. Also alot of orchestra recordings are much quieter obvioulsy due to the fact that they try to be dynamic with their music and not have everything the same volume but I find the db level of the cds to still be to low compared to what they should be which causes alot of signal noise cause I have to turnit up more, unless the noise is coming from the recording but I doubt it.

So tell me what exactly that means and why can't heaphones do it since they don't have to deal with reflections affecting the original sound?

Without getting into equal loudness curves, many people try to achieve a flat frequency response so that when you playback any recording, it is played back accurately. The relationship between soft and loud sound in a recording is important and without a flat frequency response, you are changing that relationship. For example, in the 1812 overture, the canons are a very important part of the recording. If your system roll off under 80hz, the cannons will be at a much lower level then the rest of the recording and will not have the impact they should. If your system has a large boost below 80hz, the canons will be louder then intended and could overpower the rest of the recording.

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Originally Posted by ymalmsteen887 View Post

I am know officially confirming to everyone that I believe you when you say speakers sound different and I can hear the difference between speakers in side by side comparisons I am just saying the differences are just that different and dont sound like one is better than the other.

You keep saying 50hz like it can sound any different way. 50hz is always 50hz it can't play it differently or its not 50hz. I already agreed with you awhile back that they play other sounds with it those masking the original sound but to me this is the same as playing the guitar and someone talking while they are playing its ruining the performance but is not altering the sound of the guitar's sound waves as they go through the air they are just being superimposed.

This is the point you seem to be missing. When any speaker tries to reproduce 50hz, it creates other sounds, ie distortion. In your guitar example, the person can just stop talking and stop ruining the performance. There is no way to remove distortion from a speaker. So every time the speaker plays a 50hz sound, it is creating the other sounds, which alter the overall sound. A speaker with lower distortion should sound better because it is producing these other sounds at a lower level and the "original" sound is altered less.

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Originally Posted by ymalmsteen887 View Post

Also what those people said about the speakers is not measurable. Words like Compressed, boxy, and brash need some clarification or they are just opinion.
I would assume by design a high frequency is bright, what do they mean by accurate do they know how sounds are supposed to sound all the time were they there in the studio and heard the original how do they know its accurate.
Sound has no size so it can't have width. What does better highs and mids mean all I can think of is louder. Either it plays them or not.
Crisp is a meaningless word as well and is better for describing food. Forward projected once again sound has nothing to do with size sounds feel closer when they are louder you can not hear depth there is something to refelctions that aids in if the sound is really close or not but this depends on reflections not the speakers.
Lower bass is deeper bass its just a term we say when hearing low frequencies either it plays it or not. Rich is another meaningless word. Image has to do with sight not sound. Soundstage has to do with the recording and the timing between when the left and right channels signal a sound to be played so as long as you have two speakers any stereo can do this.
Better bass control can it not tame it.
Trumpets dont have a patent on certain frequencies so this would apply to other instruments as well.
Dynamic I have listened to piano recordings on ipod headphones and can hear when they are playing louder or softer if this were true it would be like saying cheap speakers can play one voluime and more expensive speakers can play more volume levels
Imaged balanced once again the recording determines what levels each speaker plays so all things being equal the speakers wouldnt be a problem.

Dont think I said those things as fact but thats what went through my head when I read that and its that kinda of talk that lead me to this forum it doesnt make since and it sounds like wishful thinking when there isnt really anything there.

Many people would agree with you that too many people use "audiophile" terms while reviewing speakers and that measurements are more important. However, I do disagree with a few of your points. Imaging is a very real thing in the audio world. With good imaging, sounds will seem to originate at different points in your room, not just from your speakers. When a sound pans from left to right, if you have poor imaging, it will seem to jump from speaker to speaker. With good imaging it will seem to move smoothly across the entire front stage. Better mids and highs could mean lower distortion. Different speakers definitely have different dynamics and part of that is being able to play louder. Not all speakers can cleanly reach reference level when playing back a movie.

-Mike
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post #255 of 345 Old 03-04-2011, 10:59 AM
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Originally Posted by ymalmsteen887 View Post

Basically all speakers do is vibrate back and forth.

They are so much more complex than this.

The genesis of the wave is in the speaker's center and radiates outward toward the outer ring of the speaker. The waves are reflected back from the outer ring of the speaker toward the center until a standing wave is established. If you were to take a high-speed camera and record what is actually happening and zoom in really close, you will find that the speaker appears to be crawling with standing waves in addition to simply moving in and out.

This is one of the many, many reasons why two different speakers sound different. Someone pointed out a long time ago in a previous post that speaker cone materials play a part in how fast the cone reacts and that this has an affect on how it sounds as well.

Look, sound waves are a real PITA to understand. I studied them in my Senior-Level College Physics class, and if it were as easy to understand as you think they are, everyone would be speaker designing engineers.

From a strictly 100,000-foot view, I somewhat agree that you could get two comparable speakers to sound a lot alike with the proper mixing; I just have to ask myself this question: Why should I spend a ton of money on mixers and an inordinate amount of time mixing to get a crappy speaker to sound good when I can just spend a couple of hundred extra dollars to buy better speakers that don't need as much tweaking, if any at all?

I am not trying to insult you, or say you are stupid; all I'm saying is this is an extremely complex subject you are debating, and it takes more than just intuition to understand it. There is a LOT of math at work just making the very simply triangle wave I posted earlier out of a sine wave. It requires some Fourier analysis to describe it mathematically.

And for what it's worth, it is not every harmonic that goes into making a triangle wave, it's the odd harmonics that make it up...

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post #256 of 345 Old 03-04-2011, 11:36 AM - Thread Starter
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Originally Posted by WheelerM View Post

They are so much more complex than this.

The genesis of the wave is in the speaker's center and radiates outward toward the outer ring of the speaker. The waves are reflected back from the outer ring of the speaker toward the center until a standing wave is established. If you were to take a high-speed camera and record what is actually happening and zoom in really close, you will find that the speaker appears to be crawling with standing waves in addition to simply moving in and out.

Yeah but you agree that all the piston does is vibrate back and forth. What you are saying is that the outer part of the speaker vibrates later then the center. Well of course it does if I pick up a can the bottom part of the can didnt move till the chain of the atoms bonds reacted to it and carried it up with it our eyes can't see this happening its like a base ball bat when you swing it the whole thing bends but far too little for the eye to notice. Also as long as their is good dampening this shouldnt be a problem.

This is one of the many, many reasons why two different speakers sound different. Someone pointed out a long time ago in a previous post that speaker cone materials play a part in how fast the cone reacts and that this has an affect on how it sounds as well.

Thats how strings function I am not saying standing waves don't happen on speakers but when the cone moves outward the air pressure builds up and the molecules move forward.

Look, sound waves are a real PITA to understand. I studied them in my Senior-Level College Physics class, and if it were as easy to understand as you think they are, everyone would be speaker designing engineers.

From a strictly 100,000-foot view, I somewhat agree that you could get two comparable speakers to sound a lot alike with the proper mixing; I just have to ask myself this question: Why should I spend a ton of money on mixers and an inordinate amount of time mixing to get a crappy speaker to sound good when I can just spend a couple of hundred extra dollars to buy better speakers that don't need as much tweaking, if any at all?

I agree so much as the speakers are worth the price

I am not trying to insult you, or say you are stupid; all I'm saying is this is an extremely complex subject you are debating, and it takes more than just intuition to understand it. There is a LOT of math at work just making the very simply triangle wave I posted earlier out of a sine wave. It requires some Fourier analysis to describe it mathematically.

I know most things in life require more than just intuition to understand. But do you agree that the ideal speaker should just move back and forth to the changing signal?

And for what it's worth, it is not every harmonic that goes into making a triangle wave, it's the odd harmonics that make it up...

....
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post #257 of 345 Old 03-04-2011, 01:05 PM
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Originally Posted by KC Sphinx View Post

Another question to the OP or anyone who wants to help me understand.

How would an equalizer change the distortion to the waveforms?

I can see what you mean when you say that an equalizer can flatten or shape a frequency response plot. I am trying to understand how it can change the effects that a speaker has on the waveform reproduction.

*speculation disclaimer, this might not be possible or how you could actually do this*

If you had a great equalizer, you could first try to balance out so you had a flattened frequency response plot. This is conceivably possible in a relatively controlled environment with a very nice equalizer and the ability to realtime adjust the entire audio signal (probably would require some Fourier analysis to break a complicated audio signal into its component elements, and then each of these could be adjusted appropriately, and synthesized back together). You'd no longer be adjusting only specific ranges of frequencies but rather the entire signal in a continuous fashion, which probably would be a realtime computational nightmare.

If you had an amazingly great one, you might even be able to generate some destructive interference to cancel out the distortion you are getting from your "cleaned" signal. You could continually do this for a few iterations and potentially remove all distortion from the 'output' signal. You'd have to have a mic accurately reading the output from the speaker with 100% accuracy. If you put the mic close to the listening position you might even be able to somehow optimize this additional signals to make the sound the listener hears as "clean" as possible. Not sure exactly how to do this but it seems feasible (however computationally this would also be a realtime nightmare).

Lastly, you could try to understand the speakers native 'problems' and compensate. You'll never be able to eliminate some of the problems but might be able to 'fake' solutions by somehow finding and compensating for the speakers inherent mechanical properties effecting differences in output signal from input signals.
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post #258 of 345 Old 03-04-2011, 01:46 PM
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Quote:
Originally Posted by ymalmsteen887 View Post
I cant believe I used the word color. No it doesnt its just another sound I can hear the bass and the rattling. Need to get something to keep it from vibrating. Didnt you read where I said if you play the guitar and someone talks it might the persformance less enjoyable but the sound is unaltered only superimposed.
wrong again, sorry...

hint: that rattling takes energy... and that rattling gives back energy...

second hint: sure the sound of the guitar is unaltered, but that's not the point... what you "hear" is most certainly altered...

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post #259 of 345 Old 03-04-2011, 01:51 PM - Thread Starter
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Originally Posted by enderland View Post
*speculation disclaimer, this might not be possible or how you could actually do this*

If you had a great equalizer, you could first try to balance out so you had a flattened frequency response plot. This is conceivably possible in a relatively controlled environment with a very nice equalizer and the ability to realtime adjust the entire audio signal (probably would require some Fourier analysis to break a complicated audio signal into its component elements, and then each of these could be adjusted appropriately, and synthesized back together). You'd no longer be adjusting only specific ranges of frequencies but rather the entire signal in a continuous fashion, which probably would be a realtime computational nightmare.

If you had an amazingly great one, you might even be able to generate some destructive interference to cancel out the distortion you are getting from your "cleaned" signal. You could continually do this for a few iterations and potentially remove all distortion from the 'output' signal. You'd have to have a mic accurately reading the output from the speaker with 100% accuracy. If you put the mic close to the listening position you might even be able to somehow optimize this additional signals to make the sound the listener hears as "clean" as possible. Not sure exactly how to do this but it seems feasible (however computationally this would also be a realtime nightmare).

Lastly, you could try to understand the speakers native 'problems' and compensate. You'll never be able to eliminate some of the problems but might be able to 'fake' solutions by somehow finding and compensating for the speakers inherent mechanical properties effecting differences in output signal from input signals.
Why not find out how certain frequencies behave in the ideal room and then EQ the speakers according to how they play the individual frequencies and adjust everything for an idividual seating position and then when the sound is perfect you realize how it doesnt even matter anyway, lol. just kidding
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post #260 of 345 Old 03-04-2011, 02:09 PM - Thread Starter
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Originally Posted by ccotenj View Post
wrong again, sorry...

hint: that rattling takes energy... and that rattling gives back energy...

second hint: sure the sound of the guitar is unaltered, but that's not the point... what you "hear" is most certainly altered...
Let me do a theoritical situation. lets take a wall and say there is only one wall and no ceiling,floor or side walls and lets say the wall does not absord or let energy pass through it reflects energy away from it completely.Now a 20foot long bass wave is approaching the wall(does 20ft include the peak and valley of the wave) and when it hits the wall obvisouly the energy from the molecules cant pass on their energy through the wall so they get reflected back in the opposite direction. Remember there is only one 20ft wave so what happens to the molecules say two feet away from the wall after the wave has reflected?

I am trying to figure out what happens to the molecules when the compression part of the wave passes the expanded part of the wave?
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post #261 of 345 Old 03-04-2011, 02:21 PM
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I assume you do not understand interference? You never answered that question of mine.

http://en.wikipedia.org/wiki/Interfe...e_propagation)

edit -depending on how far the source is from the wall, you might get any variety of sound back from the wall.

You might get no sound (completely destructive interferences) or you might get completely constructive and double the volume.

More likely, you will get a combination which will result in some significant differences in what you hear as compared with the actual waveform.
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post #262 of 345 Old 03-04-2011, 03:53 PM
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I lied. I confess my sin. I said I was leaving this thread but I came back to see if the train wreck continues. Yeh cloud! It continues.
With all due respect to the poster, "your problem is one of language".
You twist and turn the words you use in order to question the responses of the people who are attempting to show you what you can say and can't say, to represent the complicated concepts that are involved in describing the "mechanical" device that is the speaker driver and all that it does, the "electrical" portion of the speaker drivers activity, the "recorded" portion of the input signal, the "room" in which it is being played in, and the "human" elements involved in the "hearing".
You speak of getting hit by a car going 60 miles an hour and you seem to ask whether or not the person that gets hit "instantly" gets up to speed, yet, you never continue with that example.
You have some one with college level physics training describe what happens to the speaker cone and his description involves speaking about how the cone moves in non-pistonic motion and you turn around and say "all it does is move in and out" NO it doesn't, it moves as the quite involved verbal descriptions says it moves and that means it does not just move in and out. You cannnot then say "all it does is move in and out". That is a language problem.
That means you will have to go, sentence by sentence, and agree on what words can be accurately used to describe the situation accurately. Once you decide on the correct words, you cannot then change the words, that will change the meaning.
Also, you are also committing the mistake of thinking that if you ask a question there must be an answer. That is also a fundamental mistake in usage of the language. I will give you an example.
It makes sense to say, where is the dog?
We can talk about the number 4 and say things about it, like 4 + 4 = 8. We can also say, where is 4? But it is a non sensical question. 4 does not exist somewhere.
I questioned earlier how old you were and I also questioned earlier if English was your native language. You proceeded to assume why I asked those questions. Simply, I just wanted to know how old your were and if English was your native language.
Once I knew the answers to those questions I was going to ask more questions. I eventually would have collected the information to decide whether or not you were a 'troll', whether or not you were 'serious' about trying to understand or whether you were just 'messing' with people.
I have concluded that you do not yet have the language skills to 'learn' more about this topic. That is not to say you can't get there, but only 'right now' you can't get there by continuing the way you are going.
Enjoy.....

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post #263 of 345 Old 03-04-2011, 04:11 PM
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Clearly he's just being obtuse.
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post #264 of 345 Old 03-04-2011, 05:19 PM
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Wow, I just spent many minutes going through the 260+ posts in this thread. The phrase that springs to mind is "a little knowledge is a dangerous thing".

To the OP, the field of sound reproduction is a very complex subject. I applaud you for wanting to know more about it but you have to realize that this is not a subject that can be easily conveyed especially over an Internet forum.

You think you have an understanding of the basics and that your points are valid; from your posts I can see you coming back to the same examples over and over again... this shows that you're still stuck with your preconceived notions. A lot of the posters have tried to expand your understanding but it's not happening.... yet.

Yes you want to get a handle on it, but perhaps doing it on this forum isn't the best way. You might want to attend a course on the subject, might be a better avenue to truly understand the subject.
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post #265 of 345 Old 03-04-2011, 05:21 PM
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sputter
and so obtuse he doesn't even know it?

deeper than the deepest ocean
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post #266 of 345 Old 03-04-2011, 05:31 PM
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Quote:
Originally Posted by Bone215 View Post

sputter
and so obtuse he doesn't even know it?

I hope not.
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post #267 of 345 Old 03-04-2011, 06:37 PM
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I gave up (for real this time) after this...

Quote:
Originally Posted by ymalmsteen887 View Post

No I am not familiar with electromagnets.

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post #268 of 345 Old 03-04-2011, 08:39 PM
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Quote:
Originally Posted by enderland View Post

*speculation disclaimer, this might not be possible or how you could actually do this*

If you had a great equalizer, you could first try to balance out so you had a flattened frequency response plot. This is conceivably possible in a relatively controlled environment with a very nice equalizer and the ability to realtime adjust the entire audio signal (probably would require some Fourier analysis to break a complicated audio signal into its component elements, and then each of these could be adjusted appropriately, and synthesized back together). You'd no longer be adjusting only specific ranges of frequencies but rather the entire signal in a continuous fashion, which probably would be a realtime computational nightmare.

If you had an amazingly great one, you might even be able to generate some destructive interference to cancel out the distortion you are getting from your "cleaned" signal. You could continually do this for a few iterations and potentially remove all distortion from the 'output' signal. You'd have to have a mic accurately reading the output from the speaker with 100% accuracy. If you put the mic close to the listening position you might even be able to somehow optimize this additional signals to make the sound the listener hears as "clean" as possible. Not sure exactly how to do this but it seems feasible (however computationally this would also be a realtime nightmare).

Lastly, you could try to understand the speakers native 'problems' and compensate. You'll never be able to eliminate some of the problems but might be able to 'fake' solutions by somehow finding and compensating for the speakers inherent mechanical properties effecting differences in output signal from input signals.

you would need 2 mics planted inside the ear-canal relatively close to the ear drum for the best results

every time you tilt your or move head a little you're drastically changing the response curve

a single mic in the "LP" is probably way off from what we're actually experiencing

All this noise about noise.
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post #269 of 345 Old 03-05-2011, 03:11 AM - Thread Starter
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I am not being obtuse. I agree that the best way to learn is not on this forum but now I have things to look into to see who's right and who's wrong. But I will say that the thing about the electromagnets is definetly on my side when I say the speaker moves back and forth just like you ear drum. Thats the entire purpose of the + and - on the back of the speaker if the speaker behaves wildly this would be unwanted and probably poor materials.
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post #270 of 345 Old 03-05-2011, 05:11 AM
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^^^

i'm not sure what the "best" way to learn is, but i'm pretty sure that asking questions about a topic you know nothing about and then telling those who do know what they are talking about that they are wrong isn't going to be an effective way of learning...

you still haven't bought the book i recommended to you yet, have you? if you had, you would realize how silly your assertions are...

short of that, if you really want to learn (and not just tell us we are wrong), you can accept some of the knowledge that people are trying to share with you... there's no "mystery" here, all of what you are trying to learn is very well understood...

you'll notice there's no disagreement amoungst the people who are trying to help you... on avs, the "lack of disagreement" is a VERY strong indicator that what you are being told is correct... as people here will argue over the shade of blue the sky is...

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my build thread - updated 8-20-12 - new seating installed and projector isolation solution

 

http://www.avsforum.com/t/1332917/ccotenj-finally-gets-a-projector

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