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The physics and understanding of low frequencies - Page 8

post #211 of 345
You cannot possibly make out the differences in a single speaker switching the terminals (you will be out of phase by 180 degrees, but this is nearly insignificant for one speaker).

You probably will get some weird constructive/destructive interference (do you know what this is?) though if you have two speakers which are wired differently. Would be definitely hard to actually measure considering the effect of room acoustics.

Quote:


You are comparing vibration with speed

Right. Your example is applicable - the speaker vibrates by moving back and forth. The example of a car actually is good here too - if you want to go from 0 to 50, some cars do that better. Some cars go from 50 to 70 better. Some cars go from 70 to 30 better. Speakers are doing something similar when they change frequencies (again, considerably faster). Quality of the speaker will affect how well they change frequencies in a similar manner to a car switching speeds.
post #212 of 345
Also you might want to consider your room acoustics, perhaps your room just have terrible accoustics in which case all speakers would just sound about terrible anyway.
post #213 of 345
Thread Starter 
Quote:
Originally Posted by jwickers View Post

Also you might want to consider your room acoustics, perhaps your room just have terrible accoustics in which case all speakers would just sound about terrible anyway.

Curious how could my room have terrible acoustics. Its no different than your average room as far as materials and furniture goes. Even if thats true I should still be able to hear the difference between my tv speakers and towers in the same room.
post #214 of 345
Quote:
Originally Posted by ymalmsteen887 View Post

Curious how could my room have terrible acoustics. Its no different than your average room as far as materials and furniture goes. Even if thats true I should still be able to hear the difference between my tv speakers and towers in the same room.

99% of rooms have bad acoustics. The only ones with good acoustics are the ones which have been designed and/or treated to improve acoustics. I'd dig up the Dolby manual for recording studio room design, but I don't see the point.

I can't believe you're still saying all speakers produce 50Hz the same. I went over that in length with you, even posted pictures in posts 116 and 127. I gave you links to well written articles on audio theory from Audioholics back in post 83. All we're doing is chasing our tails, going around and around in circles, and the same questions keep coming up.

Read this small excerpt from the Audioholics 2010 Speaker Faceoff:

Quote:
Originally Posted by 2010 Audioholics $1k Floorstanding Loudspeaker Faceoff View Post

When Klipsch directly compared to Axiom
Comments from trained listeners:

-Compressed and boxy sound, bass heavy with somewhat brash vocals.
-Bright highs, compressed mids, but bass a tad more accurate than other speaker.

Comments from other listeners:

-Soundstage was wider and more open than the other speaker with better highs and mids.
-Crisp bass, more forward "projected" sound but sound seemed louder in the right speaker.
-Deep rich bass with excellent imaging and soundstage.
-Better bass control than other speaker, trumpet sounds more prominent.
-Klipsch rep: great dynamic range and image balanced.

Full article here: http://www.audioholics.com/reviews/s...ff-comparisons

These tests were done under highly controlled conditions in a room which was professionally acoustically treated. How can you explain the differences these people heard? Are they lying? Are they crazy? Or are they telling the truth? If you can believe they are telling the truth, then you need to drop the whole "all speakers play 50Hz the same" mantra. If you don't, there's no point in any of us continuing this discussion.

At least some people here have learned things, like Skrillex back in post 173. Other than that, this thread is a real train wreck... I don't want to watch, but I can't look away.
post #215 of 345
Thread Starter 
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?
post #216 of 345
A bad recording or mix played on the best speakers will still sound just as bad.

Some recordings will have more noise. I've definitely noticed this myself more now that I have decent speakers.

A room sounds bad for a variety of reasons. Interference is one way you will have some problems, as are reflections.
post #217 of 345
Thread Starter 
Quote:
Originally Posted by enderland View Post

A bad recording or mix played on the best speakers will still sound just as bad.

Some recordings will have more noise. I've definitely noticed this myself more now that I have decent speakers.

A room sounds bad for a variety of reasons. Interference is one way you will have some problems, as are reflections.

I didnt say as fact my room doesnt have bad acoustics. I was asking that I should still be able to tell the differnce between cheap speakers and expensive speakers played in the same environment.
post #218 of 345
Yes and no, basically what i am trying to say is that the speaker placement and the room could make your speakers sound bad.
I know that, my current computer room has terrible echo, the speakers i have are not overly bad but i can feel how the room makes them sound worse than they could (like what they did in my previous room).

So i am sure if i put a pair of $3k floorstanders here i would get a lot of improvements.

In my living room it's a better mainly because the room is a lot bigger, the floorstanders do sound obviously better than the PC speakers.

I am also not really sure what level of obviously better you are able to discern, of if you ever head good speaker in an acoustically treated room.
post #219 of 345
Thread Starter 
Quote:
Originally Posted by DanLW View Post

99% of rooms have bad acoustics. The only ones with good acoustics are the ones which have been designed and/or treated to improve acoustics. I'd dig up the Dolby manual for recording studio room design, but I don't see the point.

I can't believe you're still saying all speakers produce 50Hz the same. I went over that in length with you, even posted pictures in posts 116 and 127. I gave you links to well written articles on audio theory from Audioholics back in post 83. All we're doing is chasing our tails, going around and around in circles, and the same questions keep coming up.

Read this small excerpt from the Audioholics 2010 Speaker Faceoff:


Full article here: http://www.audioholics.com/reviews/s...ff-comparisons

These tests were done under highly controlled conditions in a room which was professionally acoustically treated. How can you explain the differences these people heard? Are they lying? Are they crazy? Or are they telling the truth? If you can believe they are telling the truth, then you need to drop the whole "all speakers play 50Hz the same" mantra. If you don't, there's no point in any of us continuing this discussion.

At least some people here have learned things, like Skrillex back in post 173. Other than that, this thread is a real train wreck... I don't want to watch, but I can't look away.

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.

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.
post #220 of 345
Thread Starter 
Quote:
Originally Posted by jwickers View Post

Yes and no, basically what i am trying to say is that the speaker placement and the room could make your speakers sound bad.
I know that, my current computer room has terrible echo, the speakers i have are not overly bad but i can feel how the room makes them sound worse than they could (like what they did in my previous room).

So i am sure if i put a pair of $3k floorstanders here i would get a lot of improvements.

In my living room it's a better mainly because the room is a lot bigger, the floorstanders do sound obviously better than the PC speakers.

I am also not really sure what level of obviously better you are able to discern, of if you ever head good speaker in an acoustically treated room.

Do concerts in an auditorium count what about an imax theater are they acousticaly treated?
post #221 of 345
My God. I actually took two days to read all 220 posts in this thread.

Oddly enough, I think I actually understand what the OP is trying to say. Is this the scenario?

Take an iPod, hook it up to a set of computer speakers through a highly sophisticated mixing station (I mean really, really sophisticated; no expense spared in the design and construction) and mix the track so that it accurately mimics the live recording in both the frequency and time domain. Then disconnect the iPod from that system and hook it up to an identical system, except this second system is connected to a very expensive set of speakers. With proper mixing on both systems, I would not be able to tell the difference between the computer speakers and the more expensive speakers, right?

Before I board this train, I just want to be certain it's headed in the right direction.
post #222 of 345
Gosh 220 posts already ? By now the train has reached Soviet Russia, which means the train drives you.
post #223 of 345
Quote:
Originally Posted by jwickers View Post

Gosh 220 posts already ? By now the train has reached Soviet Russia, which means the train drives you.

Valid point, but I'm just now getting on...or at least, I'm thinking about getting on.

EDIT: Why do I imagine Blaine the Train from The Wastelands?
post #224 of 345
Thread Starter 
Quote:
Originally Posted by WheelerM View Post

My God. I actually took two days to read all 220 posts in this thread.

Oddly enough, I think I actually understand what the OP is trying to say. Is this the scenario?

Take an iPod, hook it up to a set of computer speakers through a highly sophisticated mixing station (I mean really, really sophisticated; no expense spared in the design and construction) and mix the track so that it accurately mimics the live recording in both the frequency and time domain. Then disconnect the iPod from that system and hook it up to an identical system, except this second system is connected to a very expensive set of speakers. With proper mixing on both systems, I would not be able to tell the difference between the computer speakers and the more expensive speakers, right?

Before I board this train, I just want to be certain it's headed in the right direction.

Yes and no. I believe the computer speakers will, depending on size, not be able to play certain lower frequencies to be audible enough,so its obvious small stock computer speakers are lacking.
What I am saying is to your example with the mixing station is if you have some speaekers that can play say frequencies from 30hz to 24khz should not sound any different than another speaker of different design that has been mixed electronicaly to match the specifications you are wanting it to do. I would say in this case is 4 drivers each speaker is all you need for the full audio specturm.
post #225 of 345
Quote:
Originally Posted by ymalmsteen887 View Post

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.

If you can create two speakers which have an identical ability to replicate a sound, all woofers on the speaker are precisely in phase, put them into a cabinet with identical acoustic properties (resonance, harmonics, etc), give the same volume for a given voltage, react equally quick to input frequencies, sit in a position in the room where reflections/echos/etc are the same, and exactly replicate the same waveform, then yes.

A 50hz input signal (even if it is just a straight sinusoid) will sound different on different speakers in different physical cabinets in different rooms.
post #226 of 345
Quote:
Originally Posted by ymalmsteen887 View Post

What I am saying is to your example with the mixing station is if you have some speaekers that can play say frequencies from 30hz to 24khz should not sound any different than another speaker of different design that has been mixed electronicaly to match the specifications you are wanting it to do. I would say in this case is 4 drivers each speaker is all you need for the full audio specturm.

Can two cars both accelerate from 0 to 60 at exactly the same speed (say 4 seconds) regardless of other factors? Let's take a Ford Focus and a Ferrari.

Seems like you should be able to tune the Focus's engine to match the Ferrari right? Just tell the engine to inject more fuel?

Why not?
post #227 of 345
Thread Starter 
Quote:
Originally Posted by enderland View Post

If you can create two speakers which have an identical ability to replicate a sound, all woofers on the speaker are precisely in phase, put them into a cabinet with identical acoustic properties (resonance, harmonics, etc), give the same volume for a given voltage, react equally quick to input frequencies, sit in a position in the room where reflections/echos/etc are the same, and exactly replicate the same waveform, then yes.

A 50hz input signal (even if it is just a straight sinusoid) will sound different on different speakers in different physical cabinets in different rooms.

I want to make sure you understand where I am coming from. The only thing that makes sounds distinguishable is the combination of frequencies and there changes in time. Our vision picks up wavelengths in multiple areas but individual points of light are one color its the combination of those varying degrees of colors that make shapes so we can isolate things and get around. So Blue always looks blue if you say there are varying degrees of blue then yes that would be first a human idea to distinguish what is obvious from another and the lighter or darker blue is a greater or softer amplitude, if its not then it is a different wavelength. So by design 50 vibrations on the ear drum will always be interpreted the same way.
post #228 of 345
Thread Starter 
Quote:
Originally Posted by enderland View Post

Can two cars both accelerate from 0 to 60 at exactly the same speed (say 4 seconds) regardless of other factors? Let's take a Ford Focus and a Ferrari.

Seems like you should be able to tune the Focus's engine to match the Ferrari right? Just tell the engine to inject more fuel?

Why not?

You are trying to put me into a corner with a comparison that doesnt work with the speakers example. moving forward depends on getting traction to pick up that speed. Lets say you are standing there in the middle of the raod and a car hits you at 60mph do you have to work your way up to that speed or is it instant. A swing doesnt have to vibrate a 4hz before you get it going to 5hz. The vibration can be slow or it can be fast it doesnt matter what frequency that is independent.
post #229 of 345
*shrug*

You are right, an identical 50hz sound (ignoring all effects of the room) should sound the same no matter what. The problem is:

Find me two speakers which can create an exact same 50hz sound (you won't be able to). It's physically impossible. I mean, it very nearly would have to defy physics to do this. So your hypothetical speaker comparison cannot actually happen.
post #230 of 345
Quote:
Originally Posted by ymalmsteen887 View Post

You are trying to put me into a corner with a comparison that doesnt work with the speakers example. moving forward depends on getting traction to pick up that speed. Lets say you are standing there in the middle of the raod and a car hits you at 60mph do you have to work your way up to that speed or is it instant. A swing doesnt have to vibrate a 4hz before you get it going to 5hz. The vibration can be slow or it can be fast it doesnt matter what frequency that is independent.

So let's ignore that part and assume the slower car has already caught up.

You are driving the same Focus and the same Ferrari at 125 mph. Will they both have the same smoothness of ride? What about performance (fuel economy)?

edit- your examples themselves have backed into a corner already! you never are going to have the situation you are comparing. Even if you do get two speakers to output an identical 50hz sound with identify effects from room/cabinet/temperature/etc, this won't help you compare speakers in any meaningful way. Because you don't listen to constant, sustained tones - music/movies/voice/etc are what you actually listen to.

You may be right: with an EQ and enough power, ignoring harmonic responses (!) or room conditions or cabinet responses, you can probably make any two speakers play a single, constant tone which sounds identical
post #231 of 345
Thread Starter 
Also I realize if a speaker is stopped from playing a note it doesnt stop perfectly with the signal but the resulting movement is insignificant and this isnt a problem why the speaker is playing. Its not like if it was vibrating at 200hz it would continue to do so. I would imagine that it would move at its own natural motion.
post #232 of 345
Thread Starter 
Quote:
Originally Posted by enderland View Post

So let's ignore that part and assume the slower car has already caught up.

You are driving the same Focus and the same Ferrari at 125 mph. Will they both have the same smoothness of ride? What about performance (fuel economy)?

So are you saying speakers dont have to vibrate at lower frequencies to vibrate at higher frequencies later?
post #233 of 345
Quote:
Originally Posted by ymalmsteen887 View Post


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.

A few questions to try and understand your thinking. Please respond to the following.

1. Frequency is just one description of a waveform. The number of cycles per second. So, do you believe that a sawtool that repeats 50 times per second will sound the same as a pure sine wave repeating 50 times per second (Both 50 Hz)?

2. Do you think that wave produced at the center of the speaker cone is or is not the same as the wave that arrives at your ear?
post #234 of 345
Thread Starter 
Quote:
Originally Posted by enderland View Post

*shrug*

You are right, an identical 50hz sound (ignoring all effects of the room) should sound the same no matter what. The problem is:

Find me two speakers which can create an exact same 50hz sound (you won't be able to). It's physically impossible. I mean, it very nearly would have to defy physics to do this. So your hypothetical speaker comparison cannot actually happen.

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?
post #235 of 345
Thread Starter 
Quote:
Originally Posted by KC Sphinx View Post

A few questions to try and understand your thinking. Please respond to the following.

1. Frequency is just one description of a waveform. The number of cycles per second. So, do you believe that a sawtool that repeats 50 times per second will sound the same as a pure sine wave repeating 50 times per second (Both 50 Hz)?

2. Do you think that wave produced at the center of the speaker cone is or is not the same as the wave that arrives at your ear?

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.
post #236 of 345
Quote:
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.

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.

I, by no means, am trying to ask trick questions. It is just the way I think of waves and what I mean when I say waves, or Hz may be different from how you are thinking.

The speaker cone moving is generating the wave/s. I was more trying to ask if you think that the wave produced at the center of a speaker cone remains unchanged, or the sum of the waves remain unchanged when they reach your ear.
post #237 of 345
Thread Starter 
Quote:
Originally Posted by KC Sphinx View Post

I, by no means, am trying to ask trick questions. It is just the way I think of waves and what I mean when I say waves, or Hz may be different from how you are thinking.

The speaker cone moving is generating the wave/s. I was more trying to ask if you think that the wave produced at the center of a speaker cone remains unchanged, or the sum of the waves remain unchanged when they reach your ear.

Are you talking about the vibrations the speaker makes? If yes then no I dont think so the air is subject to the motion of the speaker and so wouldnt alter the vibration coming from the speaker
post #238 of 345
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.
post #239 of 345
Quote:
Originally Posted by ymalmsteen887 View Post


You dont seriously mean that if I play bass in a car and it vibrates the dash that is coloring the sound?

havent been following along, but yes, vibration most certainly will color the sound.
post #240 of 345
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.
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