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post #181 of 345 Old 03-02-2011, 07:44 AM
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Originally Posted by ymalmsteen887 View Post


I know his voice was different to hide his identity. I shouldnt have used him as an example then. I mean voices male or female(mostly male because they are lower) vibrate things like your chair no humans voice is that powerful and if you turned it up enough you can feel it in your chest but its too high so this doesnt feel good. I want to know why the movie industry does this(its not just movies, also shows sitcoms anything really with reocording voices and having some woofers to play them back on).

Just curious, can you show me a layout of the room the speakers are in and your seating positions if you don't mind? Also maybe some EQ settings you have on your receiver.

I have an example of how speakers can sound different:
I own two different Samsung TVs and one sounds like people are speaking out of a tin can while the other is more acceptable. Of course having the built-in speakers pointing down towards the floor doesn't help the matter at all (what were they thinking?).
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post #182 of 345 Old 03-02-2011, 08:01 AM - Thread Starter
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Originally Posted by enderland View Post

We've been over this already. A sound wave has more factors than just frequency. Amplitude and shape contribute as well. Not to mention the other factors I am not quite as familiar with. Getting the frequency right is but one step in reproducing the sound correctly.

What might be best, honestly, is to find random songs you have never heard before with clear vocals. Try to sing them with the lead singer. You will find it difficult for several reasons, among them: you will not know the words. It will be hard to match pitch immediately. Your range might not be adequate to hit all the notes. These issues are very similar to the problems speakers face. This is true whether or not you believe me - it is a function of mechanical devices reacting to input signals. It is more obvious when using the human voice because our brain/vocal cords are far slower at processing than a receiver/speakers

Wow, I realize I dont have the qualifications to talk abou this stuff and that I can see why you guys are getting annoyed at me and I appreciate you converseing with me anyway but you did bring that up and I told you that amplitude is just the amount of displacement at that frequency so if you have a 50hz signal than the speaker will produce a certain amplitude based on how much power the amp has to make it have a bigger excursion and the enclosure and the room you are in but its still just 50hz. Shape is just more than one frequency so the original shape is always there but being changed based on the difference in amplitude now the other unwanted sounds that contribute to this may affect it but have you ever sang a note and someone else tryed to sing the same note and then lower or raise it just a bit and you heard some beating. Well I have never heard something drastic like that with speakers. If I play something with mariah careys voice it always sounds like her voice so I dont understand what you mean by sound different other than some frequencies are exaggarated or not present. I realize that it may be adifficult thing to keep harmoincs happening just like when you are in a room and your voice sounds different and that speakers do this and there is probably no such existing shape that could make them all play equally. I dont disagree that speakers will probably never compare to the original sound, well unless you made the sound from scracth for that specific speaker to produce a specific sound but speakers sounding different is a trivial issue that I havent seen any justification for. So far all you have told me was about thd and all that technical stuff but you dont actually experience that stuff what about when you want to buy a pair of spearkers how do you pick them out i mean recordings very so widely and if you listening to them at an audio store they wont sound like that at home and you cant listen to reviews cause everyone has different tastes. I just think the selling of different speakers is just a way to make money thats why they have different designs I would buy speakers just on the way they looked alone. All kinds of products out there are just to try to make money and trick people into beleiveing things to get that money.
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post #183 of 345 Old 03-02-2011, 08:04 AM - Thread Starter
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Originally Posted by Skrillex View Post

Just curious, can you show me a layout of the room the speakers are in and your seating positions if you don't mind? Also maybe some EQ settings you have on your receiver.

I have an example of how speakers can sound different:
I own two different Samsung TVs and one sounds like people are speaking out of a tin can while the other is more acceptable. Of course having the built-in speakers pointing down towards the floor doesn't help the matter at all (what were they thinking?).

I know they can sound differnt but usually this is just deviating away from the original signal and not a type of quality like two guitars sounding different. I mean you just said the other tv is fine so now you just need some bass right?
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post #184 of 345 Old 03-02-2011, 08:31 AM
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Originally Posted by ymalmsteen887 View Post


I know they can sound differnt but usually this is just deviating away from the original signal and not a type of quality like two guitars sounding different. I mean you just said the other tv is fine so now you just need some bass right?

I just plug in a $10 pair of computer speakers on the bad sounding TV and called it a day. I don't expect it to produce high quality sounds when watching movies and it's mostly for the news anyway. I know there are limitations on all mechanical devices and the TVs main focus isn't sound.
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post #185 of 345 Old 03-02-2011, 08:44 AM
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Originally Posted by ymalmsteen887 View Post

So far all you have told me was about thd and all that technical stuff but you dont actually experience that stuff what about when you want to buy a pair of spearkers how do you pick them out i mean recordings very so widely and if you listening to them at an audio store they wont sound like that at home and you cant listen to reviews cause everyone has different tastes.

Did you do the experiment with trying to sing along with an unknown song?

Once you understand experientially (since me telling you has not worked) why you cannot exactly do this you will also understand why speakers cannot exactly replicate input waveforms. If you are not musically inclined, get one of your friends who is (or a singer or something) and have them do the same thing - they will be better at it.

The same is true with speakers.
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post #186 of 345 Old 03-02-2011, 09:14 AM - Thread Starter
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Originally Posted by enderland View Post

Did you do the experiment with trying to sing along with an unknown song?

Once you understand experientially (since me telling you has not worked) why you cannot exactly do this you will also understand why speakers cannot exactly replicate input waveforms. If you are not musically inclined, get one of your friends who is (or a singer or something) and have them do the same thing - they will be better at it.

The same is true with speakers.

Someday I will prove to you scientifically that some of the things you have said are wrong. Plenty of people have stood up against the norm and shown it to be false. The human mind is being given input of something and trying to outout the same thing but there is too much of a delay to do that. A speaker cone is being giving input and output like a push pull kind of thing well exactly the same thing as sound itself in the air. A speaker isnt a consicous thing trying to copy something. You keep saying it has a shape but it doesnt thats only on a graph rpresenting the changes in time if you stop time at any giving moment the speaker is either in varying degrees forward, backward, or at the resting position. You say it like its there is a band playing trying to copy another band at the same time. Its nothing like that. The tv speakers I have are easy to understand the dialouge and including many blurays dvds video games televisions this being the case I dont know how upgrading to any kind of sound system would have difficulty hearing voices yet people claim this so it seems silly to me.
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post #187 of 345 Old 03-02-2011, 09:46 AM
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^^^

as you have no knowledge of the subject at hand, and some of the people who are trying to help you have great knowledge:

1) good luck proving them wrong
2) good luck getting further assistance

did you buy the book yet?

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post #188 of 345 Old 03-02-2011, 10:40 AM
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Quote:
Originally Posted by ymalmsteen887 View Post
I know they can sound differnt but usually this is just deviating away from the original signal and not a type of quality like two guitars sounding different. I mean you just said the other tv is fine so now you just need some bass right?
I am no expert, but here are a number of basic reasons why different speakers sound different. Some are related to deviation from the input signal, but others are design choices that can give a speaker a signature sound.

-Native on-axis frequency response. Different speakers can have very different on-axis frequency responses. Not all are perfectly flat. In some cases, I'm sure it is a conscious choice to give the speaker a certain character. In others, it's just a result of other design trade offs. In some cases this can be changed with EQ.

-Off-axis response. Speakers can have a narrow or wide off-axis response. Some speakers are dipole, bipole, have side or rear firing drivers, or drivers out of phase with each other. All of these will change the sound of the speaker and change it's interaction with the room.

-Compression. This is a big one for anyone listening at high levels. As the input level is increased, at some point every speaker's FR will change and the speaker will compress.

-Distortion. I think you are underestimating how important this is to the design and sound of a speaker. There have already been a number of posts discussing the different types of distortion and the different causes of distortion. Also, as the level is increased, it becomes much harder to keep distortion inaudible. The same speaker can sound very different when played at a low level then when it is played at high volume.

If you still believe there are different speakers and different designs solely to make money and not for any technical reason, I'm not sure if you are going to get anything else out of this thread.

-Mike
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post #189 of 345 Old 03-02-2011, 10:45 AM
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I'm sending this thread to Charlie Sheen so he can explain it to me.

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post #190 of 345 Old 03-02-2011, 10:54 AM
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If someday in the future you do prove me wrong and invent an affordable mechanical system which can both instantly and exactly move a physical system to an input signal can I have like 0.5% of the profit from it? What you are saying would revolutionize many aspects of engineering. I'd absolutely LOVE to be wrong!

The reason that example is so important is because you probably have not ever had a signals class or a controls class where you look at signal response vs inputs, etc. I can talk all day about PID or ID or overshoot or second order systems or response or damping but those won't make sense without a fair bit of background in calculus/differential equations and engineering.

You can understand however that as you follow someone else's voice, you have a slight lag. It's not a perfect process. You cannot exactly match it right away, you might sing a little too high at first, or a little too low, or maybe just slowly approach the right pitch. You can experientially see this. Your vocal cords are not great at instantaneously creating sounds with the right frequency. This same idea is present in all speakers. It happens much faster - you can normally hear these differences and understand exactly what is going on with the tone someone is singing, because it happens much slower than speaker responses.

Any system which moves will have the same issues. A speaker works by moving something back and forth. A speaker can NOT simply go from 0hz instantly to 1000hz. Do you think it can?

It might go from
0hz -> 100hz -> 250hz -> 500hz -> 800hz -> 1050hz -> 975hz -> 1010hz -> 990hz -> 1005hz -> 1001hz

This all happens very quickly (fractions of seconds). But it DOES affect sound. It makes sound seem different. Maybe slightly distorted. Maybe it's not quite as clear and sounds muddy. A whole variety of descriptive words could describe speakers like I showed there.

A better speaker might do something like (with the same time interval as above)
0hz -> 400hz -> 800hz -> 1010hz -> 998hz -> 1000hz

An ideal speaker, which is how you think all speakers work, would do this
0hz -> 1000hz



not to mention this is again only one element of speaker differences. This completely ignores any acoustic properties which show up (like harmonics or the box acoustical properties). It also assumes the speaker can fully replicate any frequency to the same level.



You are probably right on one thing though - our brain is WAY slower than a receiver or amp. The processing time is insignificant on a speaker system. Orders of magnitude smaller than the physical system. For us, I would imagine that both are relevant time lags.
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Originally Posted by ymalmsteen887 View Post
Someday I will prove to you scientifically that some of the things you have said are wrong.
lol ?

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Originally Posted by ymalmsteen887 View Post
You keep saying it has a shape but it doesnt thats only on a graph rpresenting the changes in time if you stop time at any giving moment the speaker is either in varying degrees forward, backward, or at the resting position.
Yeah speakers have no shape, again lol ?

I don't know .. i just look at my computer speaker and ooh it has a tweeter and a bigger woofer, and ooh they have different shape and materials .. why would that be ?

Maybe i just just listen at my headphones, just play them loud enough so i don't have to wear them .. ooh but they don't sound as good that way, how can that be.

I knew i should just have taken the blue pill.
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post #192 of 345 Old 03-02-2011, 11:09 AM
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I think some people are overlooking an important part of the OP's inquiry. He's not suggesting all speakers sound the same he's suggesting all speakers could be coerced into sounding the same via EQ alone. Basically that the only difference between one speaker and another is the on-axis frequency response (which is what EQ can change).

This is of course incorrect but several of the replies don't apply to this argument and may be muddying the waters for the OP unnecessarily
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post #193 of 345 Old 03-02-2011, 11:13 AM - Thread Starter
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Originally Posted by ironhead1230 View Post

-Native on-axis frequency response. Different speakers can have very different on-axis frequency responses. Not all are perfectly flat. In some cases, I'm sure it is a conscious choice to give the speaker a certain character. In others, it's just a result of other design trade offs. In some cases this can be changed with EQ.
What is native on axis response?

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Originally Posted by ironhead1230 View Post

-Off-axis response. Speakers can have a narrow or wide off-axis response. Some speakers are dipole, bipole, have side or rear firing drivers, or drivers out of phase with each other. All of these will change the sound of the speaker and change it's interaction with the room.

What is off-axis and I can see how the direction of firing can affect the way interacts with the room although I do not understand how it changes the sound of the speaker?

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Originally Posted by ironhead1230 View Post
-Compression. This is a big one for anyone listening at high levels. As the input level is increased, at some point every speaker's FR will change and the speaker will compress.
What do you mean compress I thought sound was a compression wave and what part of the speakers frequency repsonse changes the speaker cone or the enclosure. Also what does FR even mean I thought all speakers responding to the changes in voltage so it wouldnt matter what frequency you sent to it. In other words what is stopping a speaker from vibrating at any frequency?
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Originally Posted by ironhead1230 View Post

-Distortion. I think you are underestimating how important this is to the design and sound of a speaker. There have already been a number of posts discussing the different types of distortion and the different causes of distortion. Also, as the level is increased, it becomes much harder to keep distortion inaudible. The same speaker can sound very different when played at a low level then when it is played at high volume.
What is distortion I have some speakers with me right now so what do I listen for? Also what is clipping? I was thinking that most speakers above 500$ a piece wouldnt disort at reasonable listening levels. What does impedance,transient response, and speaker sensitivity mean.

Actually would it be possible for you to explain exactly what a basic speaker is made of and how it vibrates? What are the implications of the positive and negative terminals and why do you need both?
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post #194 of 345 Old 03-02-2011, 11:15 AM - Thread Starter
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lol ?



Yeah speakers have no shape, again lol ?

I don't know .. i just look at my computer speaker and ooh it has a tweeter and a bigger woofer, and ooh they have different shape and materials .. why would that be ?

Maybe i just just listen at my headphones, just play them loud enough so i don't have to wear them .. ooh but they don't sound as good that way, how can that be.

I knew i should just have taken the blue pill.
I am saying that sound is a pressure wave. Shape is just a represntation on a graph. Objects have shape sound dosent.
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post #195 of 345 Old 03-02-2011, 11:17 AM - Thread Starter
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Originally Posted by lennon_68 View Post
I think some people are overlooking an important part of the OP's inquiry. He's not suggesting all speakers sound the same he's suggesting all speakers could be coerced into sounding the same via EQ alone. Basically that the only difference between one speaker and another is the on-axis frequency response (which is what EQ can change).

This is of course incorrect but several of the replies don't apply to this argument and may be muddying the waters for the OP unnecessarily
You are completly right. I know speakers sound differnt but to me i am thinking the difference is akin to listen to one pair of speakers and changing the EQ to match anothers speakers output on a differnt EQ.
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post #196 of 345 Old 03-02-2011, 11:21 AM
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I thought we went over some of this back in my post 101:
http://www.avsforum.com/avs-vb/showt...2#post20044082
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i'm sending this thread to charlie sheen so he can explain it to me.
+1
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post #198 of 345 Old 03-02-2011, 11:24 AM
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post #199 of 345 Old 03-02-2011, 11:36 AM - Thread Starter
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Originally Posted by enderland View Post
If someday in the future you do prove me wrong and invent an affordable mechanical system which can both instantly and exactly move a physical system to an input signal can I have like 0.5% of the profit from it? What you are saying would revolutionize many aspects of engineering. I'd absolutely LOVE to be wrong!

The reason that example is so important is because you probably have not ever had a signals class or a controls class where you look at signal response vs inputs, etc. I can talk all day about PID or ID or overshoot or second order systems or response or damping but those won't make sense without a fair bit of background in calculus/differential equations and engineering.

You can understand however that as you follow someone else's voice, you have a slight lag. It's not a perfect process. You cannot exactly match it right away, you might sing a little too high at first, or a little too low, or maybe just slowly approach the right pitch. You can experientially see this. Your vocal cords are not great at instantaneously creating sounds with the right frequency. This same idea is present in all speakers. It happens much faster - you can normally hear these differences and understand exactly what is going on with the tone someone is singing, because it happens much slower than speaker responses.

Any system which moves will have the same issues. A speaker works by moving something back and forth. A speaker can NOT simply go from 0hz instantly to 1000hz. Do you think it can?

It might go from
0hz -> 100hz -> 250hz -> 500hz -> 800hz -> 1050hz -> 975hz -> 1010hz -> 990hz -> 1005hz -> 1001hz

This all happens very quickly (fractions of seconds). But it DOES affect sound. It makes sound seem different. Maybe slightly distorted. Maybe it's not quite as clear and sounds muddy. A whole variety of descriptive words could describe speakers like I showed there.

A better speaker might do something like (with the same time interval as above)
0hz -> 400hz -> 800hz -> 1010hz -> 998hz -> 1000hz

An ideal speaker, which is how you think all speakers work, would do this
0hz -> 1000hz



not to mention this is again only one element of speaker differences. This completely ignores any acoustic properties which show up (like harmonics or the box acoustical properties). It also assumes the speaker can fully replicate any frequency to the same level.



You are probably right on one thing though - our brain is WAY slower than a receiver or amp. The processing time is insignificant on a speaker system. Orders of magnitude smaller than the physical system. For us, I would imagine that both are relevant time lags.
What you have brought up here is interesting and explains why we dont see things the same way. I didnt think of speakers working that way. It sounds like you are saying the speaker has to work its way up to that frequency. I was giong to say by definition it has to play 1000 times a second or 500 times every half a second etc.. to be a 1000hz frequency if it did anything else it wouldnt be 1000hz. Why would it have to work its way up to that frequency? In music you hear the raiseing and lowering of pitch on certain instruments like guitar bending, sliding, tuning etc but isnt the speaker just reacting to a positive voltage and then being given a chance to come back and then gets another push? If you knock over dominos they dont have to decide to fall over or work there way up or anything its just the result of particles hitting each other, by that logic that would mean my ear has to work its way up to a frequency starting from zero. lets take a 1hz frequency for example that would mean that something is moving forward at a certain rate depending on amplitude beacuse of something putting energy into it. Also its moving back and forth so the rate at which it moves back and forth is the frequency. If you are running you dont go from zero to fifty instantly but then again the word instant is just an idea nothing is iinstant, anyways you are trying to acheive a certain speed. You are comparing vibration with speed, if the speaker has to vibrate at 1hz and goes at 1mph from its resting position then that would be a certain amplitude but if it goes 2mph at that frequency it is going to have a greater amplitude. It doesnt have to move back and forth 2 times then 4 then 5, 6, 8 ,34, 76, etc to get to a certain frequency. If I am wrong show this is the frist time I have ever heard this.
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post #200 of 345 Old 03-02-2011, 11:37 AM - Thread Starter
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I thought we went over some of this back in my post 101:
http://www.avsforum.com/avs-vb/showt...2#post20044082
you just went from saying everone was off subject to why are you still talking about this.
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post #201 of 345 Old 03-02-2011, 11:51 AM - Thread Starter
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Originally Posted by lennon_68 View Post

The part about magnets is hard to follow. Can the speaker be made to be attracted to one side and stay there? If this doesnt make since sorry but I dont really know some of the things its talking about to know how describe what I am saying.
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post #202 of 345 Old 03-02-2011, 12:18 PM
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What is off-axis and I can see how the direction of firing can affect the way interacts with the room although I do not understand how it changes the sound of the speaker?
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you just went from saying everone was off subject to why are you still talking about this.
Should have been more specific. The post I linked to (#101) was on subject. You didn't comment on it so I assumed it made sense but then you said just now that you don't understand how the off-axis response can change the sound of the speaker - which I specifically addressed in post 101.
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post #203 of 345 Old 03-02-2011, 12:21 PM
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The part about magnets is hard to follow. Can the speaker be made to be attracted to one side and stay there? If this doesnt make since sorry but I dont really know some of the things its talking about to know how describe what I am saying.
Are you familiar with how electromagnets work? As for the second question, yes but you don't (or rather shouldn't) have this scenario in a speaker playing music. You can take a speaker driver and connect a 9v battery across its' terminals to see this. ONLY DO THIS TEST WITH A WOOFER - a tweeter will choke on this test. If you hook up the 9v batter + and - to the corresponding + and - of the speaker the cone will move out and stay out, if you hook it up in reverse (+ to -) the cone will move in and stay in. This is a standard test to see if your speaker driver is working and wired correctly.
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post #204 of 345 Old 03-02-2011, 12:53 PM
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Originally Posted by ymalmsteen887 View Post

What is native on axis response?

On axis response is basically the response of the speaker measured directly in front of and in line with the speaker. Native means without any type of EQ. See this link.

Quote:
Originally Posted by ymalmsteen887 View Post

What is off-axis and I can see how the direction of firing can affect the way interacts with the room although I do not understand how it changes the sound of the speaker?

Off-axis is anything other than on-axis. By changing how the speaker interacts with the room, that is changing the sound of the speaker. When listening to a speaker in a room, you not only hear the direct sound from the speaker, you are also hearing reflected sound off the walls, ceiling, floor and any other boundaries in the room. Different off-axis responses and different driver orientations will cause different types of reflections and will cause the speaker to sound different.

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Originally Posted by ymalmsteen887 View Post

What do you mean compress I thought sound was a compression wave and what part of the speakers frequency repsonse changes the speaker cone or the enclosure.

When I mentioned compression, I was talking about power compression. Basically, when a speaker is behaving normally, increasing the input signal by 3db will increase the output by 3db. At some point, an increase at the input, will not have the same increase at the output. That is compression. See this graph.


I'm not sure what you mean by "what part of the speakers frequency response changes the speaker cone or the enclosure."

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Originally Posted by ymalmsteen887 View Post

Also what does FR even mean I thought all speakers responding to the changes in voltage so it wouldnt matter what frequency you sent to it. In other words what is stopping a speaker from vibrating at any frequency?

The FR, or frequency response, is one of the most basic measurements of a speaker. Every speaker will have a spec similar to the following: 60hz-20khz (+-3db) This means that given the same level input, the speaker's output level between this range will be within +-3db. It also means, below that range, the output will be significantly lower. See graph above.

You are correct, if there are no crossovers involved, there is nothing stopping a speaker from vibrating at any frequency, but not all drivers can reproduce all frequencies cleanly or at a usable spl. Do you think a 21" subwoofer driver, which is heavy and has a stiff spider is suitable to vibrate fast enough to cleanly produce 18khz at a usable spl? Or that a 1" tweeter can move enough air to produce 10hz at a usable spl?

Quote:
Originally Posted by ymalmsteen887 View Post

What is distortion I have some speakers with me right now so what do I listen for? Also what is clipping? I was thinking that most speakers above 500$ a piece wouldnt disort at reasonable listening levels.

Simply put, distortion is any sound produced that was not in the input signal. There are too many kinds of distortion to easily say what distortion sounds like.
There are a couple different forms of clipping. Here is a page discussing clipping. All speakers distort at all levels. No speaker can reproduce the input signal perfectly. The question is when does the distortion become significant enough to be audible. Most speakers won't distort significantly at "reasonable" levels in your average room.

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Originally Posted by ymalmsteen887 View Post

What does impedance,transient response, and speaker sensitivity mean. Actually would it be possible for you to explain exactly what a basic speaker is made of and how it vibrates? What are the implications of the positive and negative terminals and why do you need both?

Google is your friend for questions like these. Searching for "how a speaker works" comes up with a lot of links.

Take a read through this link: http://www.hometheatershack.com/foru...explained.html

It is only discussing testing and measuring subwoofers, but it is a good read. Testing speakers is much more complicated.

-Mike
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post #205 of 345 Old 03-02-2011, 02:19 PM - Thread Starter
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Originally Posted by lennon_68 View Post

Are you familiar with how electromagnets work? As for the second question, yes but you don't (or rather shouldn't) have this scenario in a speaker playing music. You can take a speaker driver and connect a 9v battery across its' terminals to see this. ONLY DO THIS TEST WITH A WOOFER - a tweeter will choke on this test. If you hook up the 9v batter + and - to the corresponding + and - of the speaker the cone will move out and stay out, if you hook it up in reverse (+ to -) the cone will move in and stay in. This is a standard test to see if your speaker driver is working and wired correctly.

By doing this does it add too the maximum excursion possible and why will the tweeter choke is it too much voltage?

No I am not familiar with electromagnets.
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post #206 of 345 Old 03-02-2011, 02:30 PM - Thread Starter
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Originally Posted by ironhead1230 View Post

On axis response is basically the response of the speaker measured directly in front of and in line with the speaker. Native means without any type of EQ. See this link.



Off-axis is anything other than on-axis. By changing how the speaker interacts with the room, that is changing the sound of the speaker. When listening to a speaker in a room, you not only hear the direct sound from the speaker, you are also hearing reflected sound off the walls, ceiling, floor and any other boundaries in the room. Different off-axis responses and different driver orientations will cause different types of reflections and will cause the speaker to sound different.



When I mentioned compression, I was talking about power compression. Basically, when a speaker is behaving normally, increasing the input signal by 3db will increase the output by 3db. At some point, an increase at the input, will not have the same increase at the output. That is compression. See this graph.


I'm not sure what you mean by "what part of the speakers frequency response changes the speaker cone or the enclosure."

Does the speaker cone or enclosure change the frequency response you mentioned?



The FR, or frequency response, is one of the most basic measurements of a speaker. Every speaker will have a spec similar to the following: 60hz-20khz (+-3db) This means that given the same level input, the speaker's output level between this range will be within +-3db. It also means, below that range, the output will be significantly lower. See graph above.

You are correct, if there are no crossovers involved, there is nothing stopping a speaker from vibrating at any frequency, but not all drivers can reproduce all frequencies cleanly or at a usable spl. Do you think a 21" subwoofer driver, which is heavy and has a stiff spider is suitable to vibrate fast enough to cleanly produce 18khz at a usable spl? Or that a 1" tweeter can move enough air to produce 10hz at a usable spl?

Yeah I know that a tweeter would not be good for producing a 20hz frequency because it can not move enough air but a bigger speaker should be able to play as well as a smaller speaker cause wouldnt its excursion not have to be as large as the smaller speaker to have the same volume, unless it can't vibrate at that frequecny at all but high frequencies travel through walls so why does its area matter?



Simply put, distortion is any sound produced that was not in the input signal. There are too many kinds of distortion to easily say what distortion sounds like.
There are a couple different forms of clipping. Here is a page discussing clipping. All speakers distort at all levels. No speaker can reproduce the input signal perfectly. The question is when does the distortion become significant enough to be audible. Most speakers won't distort significantly at "reasonable" levels in your average room.

What do you mean "reasonable" as in no one listens at those levels?


Google is your friend for questions like these. Searching for "how a speaker works" comes up with a lot of links.

Take a read through this link: http://www.hometheatershack.com/foru...explained.html

It is only discussing testing and measuring subwoofers, but it is a good read. Testing speakers is much more complicated.

-Mike

.....
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post #207 of 345 Old 03-03-2011, 02:06 PM - Thread Starter
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Quote:
Originally Posted by lennon_68 View Post

Are you familiar with how electromagnets work? As for the second question, yes but you don't (or rather shouldn't) have this scenario in a speaker playing music. You can take a speaker driver and connect a 9v battery across its' terminals to see this. ONLY DO THIS TEST WITH A WOOFER - a tweeter will choke on this test. If you hook up the 9v batter + and - to the corresponding + and - of the speaker the cone will move out and stay out, if you hook it up in reverse (+ to -) the cone will move in and stay in. This is a standard test to see if your speaker driver is working and wired correctly.

Why does it matter which way you wire the terminals cause I switched them and the sound didn't change?
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He is talking about a battery aka DC, so depending on which way you wire it the woofer will move in or out and stay there till you remove the connection.
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post #209 of 345 Old 03-03-2011, 03:59 PM - Thread Starter
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Originally Posted by darkhorror View Post

He is talking about a battery aka DC, so depending on which way you wire it the woofer will move in or out and stay there till you remove the connection.

I knew what he was talking about there I was asking something else about how they say to make sure the terminals from your reciver to your speaker are wired correctly but when I switched between them the sound didnt change. Whats up with this just another reason why I find inconsistentcies with what I read and then actually do?
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They won't sound any different as long as they are both wired the same way. But if you wire one speaker one way then the other speaker another they won't sound correct. The imaging will be thrown out of phase.
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