Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs - Page 256 - AVS Forum
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post #7651 of 11894 Old 12-29-2013, 04:52 PM
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Quote:
Originally Posted by jim19611961 View Post

I think the first thing is what graph do you want interpreted?

It was as I had mentioned, to determine how FR measurement changes corellated to changes in what is heard with respect to surround/LCR integration. I am beginning to see that that is probably not what REW is used for.

Jeff


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post #7652 of 11894 Old 12-29-2013, 06:01 PM
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Ok.. Did couple more runs today.. Used 1/6 smoothing. And 5-20k run.
RED: Antimode Dual Core 2.0 EQ bypassed
GREEN: Antimode Dual Core 2.0 EQ ON
BLUE: Antimode Dual Core 2.0 House curve created

Thanks guys.. This is fun! Not bad for a hundred dollar investment..biggrin.gif

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post #7653 of 11894 Old 12-29-2013, 06:18 PM
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Here's another with a little aggressive house curve. Not too bad.. Might run this with Elysium today. biggrin.gif

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post #7654 of 11894 Old 12-29-2013, 06:36 PM
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Originally Posted by rhed View Post


That seems like a really subtle difference. Is it easily audible or do you have to concentrate to hear it?

(My hearing is crap so I don't think I'd hear it).
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post #7655 of 11894 Old 12-29-2013, 06:49 PM
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Originally Posted by artur9 View Post

That seems like a really subtle difference. Is it easily audible or do you have to concentrate to hear it?

(My hearing is crap so I don't think I'd hear it).
Hmm, how do I describe it. Well one thing since im on a suspended floor my whole HT shakes when I run the 10 hz sine wave on the generator. MV is at 100dbs. I don't know but its more like a deep, whirling, kind of noise. Kind of irritating actually. Kind of like you know when your driving on the hi way and you open one window in the back to let air in? And the rest of the windows is closed? Kind of like that if you know what I mean. Maybe Im not describing it right..
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post #7656 of 11894 Old 12-29-2013, 07:10 PM
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Originally Posted by rhed View Post

Kind of like you know when your driving on the hi way and you open one window in the back to let air in? And the rest of the windows is closed? Kind of like that if you know what I mean.

I know exactly what you mean. Feels like your ears are going to explode. The improvements I'm trying to make are nowhere near as subtle as yours.

I've been trying to get my measurements to look as good as yours. I've been tweaking my subs for it seems like forever smile.gif I switched in a dedicated sub amp for some passive amps I have, which brought back some sub-40Hz frequency. But that screwed up the flatness I had before.

I read some Geddes papers and so I understood better why tweaking my powered amp's volume and crossovers had the effect they do. So I set my prepro to send a full spectrum signal out the LFE (which goes to my powered amp). Then I tweaked its volume and crossover to get to a flatter curve. Since the passives are powered off a single sub amp I can't tweak them separately. Even so, I like the improvement I'm seeing.

Here's the obligatory graph. BTW, has anyone else noticed that if you run REW for a long time (2-3 hours) it starts to misbehave? For example, on the blue graph that wavy characteristic in the lower frequencies goes away if I restart REW and remeasure. Sometimes, it also goes deaf and I have to restart it. Or maybe it's if you keep more than 10-15 measurements open?
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post #7657 of 11894 Old 12-29-2013, 07:13 PM
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Quote:
Originally Posted by pepar View Post

It was as I had mentioned, to determine how FR measurement changes corellated to changes in what is heard with respect to surround/LCR integration. I am beginning to see that that is probably not what REW is used for.

Jeff

In the same way that FR changes correlate to what is heard with (a simple) LR integration.

Here is an old graph of my 5.1 setup.



The rears have a dip of 5dB or so around 400-700hz.
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post #7658 of 11894 Old 12-30-2013, 07:21 AM
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Quote:
Originally Posted by AustinJerry View Post

Really, Jeff? This sounds like a not-so-subtle response to Keith's claim that if he can't measure it, then it doesn't exist (or something to that effect). 

 

Just for the avoidance of doubt, Jerry, my assertion was that everything which can be heard can be measured. Nobody can sensibly dispute that, and if they do then they are ignorant of the facts.

 

The reasoning behind my assertion is that we know that for some time the sensitivity of measuring equipment has exceeded that of human hearing. Therefore it follows that everything in the human audible range of hearing can be measured.

 

Of course, as we know in this thread only too well, the converse is not true. Everything which can be measured cannot be heard. The reasoning behind that assertion is precisely the same as given above. Thus, the measuring equipment available to even us hobbyists is more than capable of measuring things which we cannot possibly hear, and which we can then safely ignore. Not to ignore this can cause outbreaks of graphitis nervosa.  

 

Conversely, if someone makes a subjective claim that they can 'hear something' - things like 'better clarity' or 'deeper bass' or 'tighter bass' or 'smoother midrange' or 'better imaging' etc etc etc, then these things will show up on measurements. If they cannot be shown via measurements, then it is reasonable to question whether what can be heard is real, or imaginary, or the result of expectation bias and so on.

 

So, to reassert for anyone in even the vaguest doubt about what I said: everything which can be heard can be measured.

 

If anyone has any objective proof that there are things which human beings can hear but which are incapable of being measured, they can take this as their invitation to share this with us.

 

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 Personally, I would prefer that the debate that has been going on in the Pro thread stay in that thread, and not spill over into this thread. Would that be too much to ask?

 

Heartily concurred.

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post #7659 of 11894 Old 12-30-2013, 07:53 AM
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Quote:
Originally Posted by kbarnes701 View Post

Just for the avoidance of doubt, Jerry, my assertion was that everything which can be heard can be measured. Nobody can sensibly dispute that, and if they do then they are ignorant of the facts.

The reasoning behind my assertion is that we know that for some time the sensitivity of measuring equipment has exceeded that of human hearing. Therefore it follows that everything in the human audible range of hearing can be measured.

Of course, as we know in this thread only too well, the converse is not true. Everything which can be measured cannot be heard. The reasoning behind that assertion is precisely the same as given above. Thus, the measuring equipment available to even us hobbyists is more than capable of measuring things which we cannot possibly hear, and which we can then safely ignore. Not to ignore this can cause outbreaks of graphitis nervosa.  

Conversely, if someone makes a subjective claim that they can 'hear something' - things like 'better clarity' or 'deeper bass' or 'tighter bass' or 'smoother midrange' or 'better imaging' etc etc etc, then these things will show up on measurements. If they cannot be shown via measurements, then it is reasonable to question whether what can be heard is real, or imaginary, or the result of expectation bias and so on.

So, to reassert for anyone in even the vaguest doubt about what I said: everything which can be heard can be measured.

If anyone has any objective proof that there are things which human beings can hear but which are incapable of being measured, they can take this as their invitation to share this with us.


Heartily concurred.

The part in italics may be true in many instances, but may not be in others given a single located mic wont measure what two ears can. I don't think there is any measurement for instance that defines or measures sound-stage if for no other reason than my previous statement. I.E. soundstage requires two auditory inputs. Envelopment may be another. Spaciousness still another. Comb Filtering?

I would say that measurements CANT tell you how something sounds. But measurements CAN tell you something about some of the aspects of what we hear. In the same way, one could measure the texture, grain, and smoothness of an apple skin and its weight. But that still wouldn't tell you what it feels like to hold an apple.

Edit:

Spaciousness for instance. What are its component parts?

1) Reflections (magnitude and timing)
2) Decay/RT60
3) Frequency content of those reflections (the FR curve for individual and/or groups of reflections)
4) Direction from which reflections occur (direction in conjunction with their timing and magnitude)
5) Defuse vs specular distribution of observed reflections

(there maybe more, this is just what came to the top of my mind first)

So lets see how well we can measure each of these.

1) ETC gives us a pretty good take here - CHECK
2) CHECK
3) Here is where missing data begins to occur. Slicing ETC's give some measure of this, but full band ETC's are what most people use and tells us nothing about this. PARTIAL CHECK
4) NO DATA
5) NO DATA

Envelopment - Do we really even have a definition of this experience? Much less what its measurable constituent parts are? But we all know what this is in the listening experience, don't we?

Comb Filtering - We know this affects how things sound. Do we have a measure for it? While unsmoothed FR's give us some sense about it, we don't have a yardstick to apply to it to tell us whats good or bad, much less any definitive comparative data.
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post #7660 of 11894 Old 12-30-2013, 10:21 AM
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Jeff/pepar is essentially asking the same question I asked the other day. Which has to do with interpreting the data in REW to best practical effect (i.e. removing the clutter of noise at the low end, for one thing), and correlating what I see with what I hear.

I largely agree with him in that I have not made any SQ choices solely using REW so far, rather REW has more or less confirmed the ones I made *over many years* by ear. It shows me why I probably made the decisions I made, in that the other options were worse overall lol. And it shows me what the problems are. I also mentioned the other day that very significant auditory changes in the bass region (from traps in this case) did not cause huge glaring changes in the REW graphs here, but rather more subtle changes over a wider range that are very easily heard by somebody quite used to how their system sounds in that room. That is where the experience factor comes in. Presumably if I remove the problems to a much larger extent, then the graphs will show it more obviously. Repeat: small changes in treatments can have clearly audible results but show small changes in the graphs *unless you work at it*. I am just learning how to work at it:

One thing that may help in correlating measurements of room/system changes with what you hear, and again I'm just getting into this aspect, is to subtract your measurement readings from one another, and look at the waterfalls of those. For instance, before and after the installation of a couple panels, or some traps. So you can see all the small changes across the whole audio band...clears some things up, literally. Do it the same as how I mentioned doing it for noise the other day. May not be scientifically the greatest, but is "engineeringly" good enough to work from.
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post #7661 of 11894 Old 12-30-2013, 11:12 AM
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I'm with Jim on this one. We do not know everything we should be measuring that equates to what we can hear. Then there's the limitation of our available measuring apparatus (single mic vs quad mic like Trinnov, resolution, etc).

Then there's the fact that our brain interprets the signals in ways that REW cannot show.

When I worked with scientists trying to develop speech recognition software they could do the Fourier transforms of the vocalizations. But when it came time to recognize phrases like "It's hard to wreck a nice beach" a fair amount of linguistic horsepower had to be applied to realize that phrase should have been "It's hard to recognize speech." That psycho-acoustics/linguistics isn't available to our software and may not even be desirable.
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post #7662 of 11894 Old 12-30-2013, 11:36 AM
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Not sure where to ask this so here goes:

Question

Should I measure left sub only. Then apply a dsp to it. Then measure right sub only and apply an eq to it

Or apply one eq for the left and right sub measured together? (Copies to both outputs)

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post #7663 of 11894 Old 12-30-2013, 12:10 PM
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Quote:
Originally Posted by cfraser View Post

Jeff/pepar is essentially asking the same question I asked the other day. Which has to do with interpreting the data in REW to best practical effect (i.e. removing the clutter of noise at the low end, for one thing), and correlating what I see with what I hear.

I largely agree with him in that I have not made any SQ choices solely using REW so far, rather REW has more or less confirmed the ones I made *over many years* by ear. It shows me why I probably made the decisions I made, in that the other options were worse overall lol. And it shows me what the problems are. I also mentioned the other day that very significant auditory changes in the bass region (from traps in this case) did not cause huge glaring changes in the REW graphs here, but rather more subtle changes over a wider range that are very easily heard by somebody quite used to how their system sounds in that room. That is where the experience factor comes in.

I had the same experience with REW and traps. The FR showed some change/flattening, but the waterfall was dramatically better. And as you say, removing the overhang of ringing bass modes made EVERYTHING sound better.

Jeff


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Quote:
Originally Posted by Brian Fineberg View Post

Not sure where to ask this so here goes:

Question

Should I measure left sub only. Then apply a dsp to it. Then measure right sub only and apply an eq to it

Or apply one eq for the left and right sub measured together? (Copies to both outputs)

When I was reading up on how Geddes recommends placing multiple subs he said, IIRC, you place the first one and make it's response as good as you could. Then you place the second one and adjust only it to make the response better. But he recommends 3 subs and wants them placed randomly, with the 3rd above ear level.

I think there's a link to his placement methodology in this thread. But here's a non-canonical version
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Originally Posted by artur9 View Post

I'm with Jim on this one. We do not know everything we should be measuring that equates to what we can hear. Then there's the limitation of our available measuring apparatus (single mic vs quad mic like Trinnov, resolution, etc).

Then there's the fact that our brain interprets the signals in ways that REW cannot show.


When I worked with scientists trying to develop speech recognition software they could do the Fourier transforms of the vocalizations. But when it came time to recognize phrases like "It's hard to wreck a nice beach" a fair amount of linguistic horsepower had to be applied to realize that phrase should have been "It's hard to recognize speech." That psycho-acoustics/linguistics isn't available to our software and may not even be desirable.

Well, BINGO! Our auditory sense and "algorithms" have been perfected over hundreds of thousands of years.

Jeff


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Quote:
Originally Posted by Brian Fineberg View Post

Not sure where to ask this so here goes:

Question

Should I measure left sub only. Then apply a dsp to it. Then measure right sub only and apply an eq to it

Or apply one eq for the left and right sub measured together? (Copies to both outputs)

Measuring one sub will measure it's interaction with the room. Measuring all subs simultaneously will measure their interaction with the room AND EACH OTHER.

Jeff


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post #7667 of 11894 Old 12-30-2013, 12:19 PM
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Quote:
Originally Posted by Brian Fineberg View Post

Not sure where to ask this so here goes:

Question

Should I measure left sub only. Then apply a dsp to it. Then measure right sub only and apply an eq to it

Or apply one eq for the left and right sub measured together? (Copies to both outputs)


Not sure if there is a "right way".  I would invest the time to try it both ways, measuring each result and picking the best one.

 

Edit:  I agree with Jeff, and if I were to guess, I would pick the approach that applies DSP to the combined signals of both subs.


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Ok. I on fact eq'd them based on them both at the same time

Just making sure there wasn't a better method

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post #7669 of 11894 Old 12-30-2013, 12:58 PM
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Quote:
Originally Posted by jim19611961 View Post
 
Quote:
Originally Posted by kbarnes701 View Post

Just for the avoidance of doubt, Jerry, my assertion was that everything which can be heard can be measured. Nobody can sensibly dispute that, and if they do then they are ignorant of the facts.

The reasoning behind my assertion is that we know that for some time the sensitivity of measuring equipment has exceeded that of human hearing. Therefore it follows that everything in the human audible range of hearing can be measured.

Of course, as we know in this thread only too well, the converse is not true. Everything which can be measured cannot be heard. The reasoning behind that assertion is precisely the same as given above. Thus, the measuring equipment available to even us hobbyists is more than capable of measuring things which we cannot possibly hear, and which we can then safely ignore. Not to ignore this can cause outbreaks of graphitis nervosa.  

Conversely, if someone makes a subjective claim that they can 'hear something' - things like 'better clarity' or 'deeper bass' or 'tighter bass' or 'smoother midrange' or 'better imaging' etc etc etc, then these things will show up on measurements. If they cannot be shown via measurements, then it is reasonable to question whether what can be heard is real, or imaginary, or the result of expectation bias and so on.

So, to reassert for anyone in even the vaguest doubt about what I said: everything which can be heard can be measured.

If anyone has any objective proof that there are things which human beings can hear but which are incapable of being measured, they can take this as their invitation to share this with us.


Heartily concurred.

The part in italics may be true in many instances, but may not be in others given a single located mic wont measure what two ears can. I don't think there is any measurement for instance that defines or measures sound-stage if for no other reason than my previous statement. I.E. soundstage requires two auditory inputs. Envelopment may be another. Spaciousness still another. Comb Filtering?

I would say that measurements CANT tell you how something sounds. But measurements CAN tell you something about some of the aspects of what we hear. In the same way, one could measure the texture, grain, and smoothness of an apple skin and its weight. But that still wouldn't tell you what it feels like to hold an apple.

Edit:

Spaciousness for instance. What are its component parts?

1) Reflections (magnitude and timing)
2) Decay/RT60
3) Frequency content of those reflections (the FR curve for individual and/or groups of reflections)
4) Direction from which reflections occur (direction in conjunction with their timing and magnitude)
5) Defuse vs specular distribution of observed reflections

(there maybe more, this is just what came to the top of my mind first)

So lets see how well we can measure each of these.

1) ETC gives us a pretty good take here - CHECK
2) CHECK
3) Here is where missing data begins to occur. Slicing ETC's give some measure of this, but full band ETC's are what most people use and tells us nothing about this. PARTIAL CHECK
4) NO DATA
5) NO DATA

Envelopment - Do we really even have a definition of this experience? Much less what its measurable constituent parts are? But we all know what this is in the listening experience, don't we?

Comb Filtering - We know this affects how things sound. Do we have a measure for it? While unsmoothed FR's give us some sense about it, we don't have a yardstick to apply to it to tell us whats good or bad, much less any definitive comparative data.

 

I'm not sure, Jim. 'Soundstage' is perhaps easier to deal with. By 'soundstage' I assume you mean the spatial distribution of sounds around and between the speakers (and above and behind them too if you like). I think this is the same thing as 'imaging' and I am fairly sure that we can look at room measurements and form a conclusion as to whether the system will image well. ETCs should tell us a lot about this I think. A system with poor ETCs will be very unlikely to image well, and if that is the case, then the 'soundstage' will be poor. The better the imaging the better the soundstage, so I do think measurements will reveal a lot here.

 

As for 'spaciousness' I am not sure what this is. A small jazz combo recorded in a club should not have 'spaciousness'. A movie scene set in a mountain range may well have a great sense of space recorded into the soundtrack and reproduced by various speakers located around the listening room. An orchestra in large hall will reflect the ambiance of that hall and so on. I don't think there is any such thing as 'spaciousness' and I think it is one of these 'audiophile' terms which audiophiles bandy around, but which actually doesn't really have much meaning. As such, it will indeed be difficult to measure it of course. If it can't even be described, I'd think it would be hard to measure. Please don't take offence at my remarks as none is intended and I am not referring to you as an individual here.

 

Note that I am not saying at all that because everything that we can hear can be measured that measurements are the be-all and end-all. Ultimately it is listening which matters and we do that with our ears not with mics and software. But I think I will hold my position on this, unless something very persuasive comes along to convince me that there are indeed things we can hear that we cannot measure.



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post #7670 of 11894 Old 12-30-2013, 01:42 PM
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Quote:
Originally Posted by Brian Fineberg View Post

Not sure where to ask this so here goes:

Question

Should I measure left sub only. Then apply a dsp to it. Then measure right sub only and apply an eq to it

Or apply one eq for the left and right sub measured together? (Copies to both outputs)

First find locations for the subs that results in the lowest point to point variance within the listening area. Then equalize both subs as one.

Here's an example: http://mehlau.net/audio/multisub_multeq_xt32/
Setup A shows lower point to point differences. Setup B is worse. The variance is maintained after equalization.
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post #7671 of 11894 Old 12-30-2013, 01:42 PM
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Originally Posted by kbarnes701 View Post

I'm not sure, Jim. 'Soundstage' is perhaps easier to deal with. By 'soundstage' I assume you mean the spatial distribution of sounds around and between the speakers (and above and behind them too if you like). I think this is the same thing as 'imaging' and I am fairly sure that we can look at room measurements and form a conclusion as to whether the system will image well. ETCs should tell us a lot about this I think. A system with poor ETCs will be very unlikely to image well, and if that is the case, then the 'soundstage' will be poor. The better the imaging the better the soundstage, so I do think measurements will reveal a lot here.

No. Sounstage IMO is not the lingering reflections in a room but rather the speakers ability to convey the phase response properly as to have an illusion of 3-dimensionsional locations for instruments on a stage. And to the extent that the room around the speakers lets them do this. The direct response is completely responsible for the soundstage. The rooms purpose is to provide bass reinforcement and ambiance, not to be the source of secondary images. In the case where you have intentionally delayed reflections/diffusion, the purpose is to reinforce the images created by the direct response through the use of masking later arriving ones. Later arriving reflections psycho-acoustically (after 40ms or so) we interpret as distinct and separate from those of the direct response via their delay in time. So the images formed by the direct response seem more clear and defined without later arriving energies distracting us.

What you seem to be calling soundstage I would call ambiance or liveliness.


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As for 'spaciousness' I am not sure what this is. A small jazz combo recorded in a club should not have 'spaciousness'. A movie scene set in a mountain range may well have a great sense of space recorded into the soundtrack and reproduced by various speakers located around the listening room. An orchestra in large hall will reflect the ambiance of that hall and so on. I don't think there is any such thing as 'spaciousness' and I think it is one of these 'audiophile' terms which audiophiles bandy around, but which actually doesn't really have much meaning. As such, it will indeed be difficult to measure it of course. If it can't even be described, I'd think it would be hard to measure. Please don't take offence at my remarks as none is intended and I am not referring to you as an individual here.

Spaciousness is what I define as the sense of being in a room that sounds bigger than it really is. But to help with dispelling this as audiophile jargon I will add this:

Pretend you and I are in a room and you are blind folded. Suppose you have never seen the room or in any fashion, did you know ahead of time how big it was. I then asked you during conversation to guess how big the room was based on how it sounded. What you would do to determine this is listen to how long the delay was from my voice to the earliest reflection plus those arriving after it. This would give you the cue your brain needs for this type of discernment. Now, lets say acoustically, I made it so the same exact room, I used treatment to make the first reflection you could hear twice as long in time. Blind folded, you would have no recourse than to think the room was much larger than before. Thus achieved by a anechoic room response for the first 20ms, then followed by a strong return. In such a case, you have made the first reflection from the music 20ms which takes 22.5' or almost 7 meters to traverse . I am sure you can see where this is going.....

So yes. Spaciousness can be achieved by the proper delay, bandwidth and direction of reflections. The exact character of that spaciousness is a slightly different conversation.


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Note that I am not saying at all that because everything that we can hear can be measured that measurements are the be-all and end-all. Ultimately it is listening which matters and we do that with our ears not with mics and software. But I think I will hold my position on this, unless something very persuasive comes along to convince me that there are indeed things we can hear that we cannot measure.

I already pointed out things we cant and don't measure..


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post #7672 of 11894 Old 12-30-2013, 01:52 PM
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Ok. I on fact eq'd them based on them both at the same time

Just making sure there wasn't a better method

There is a better method but it requires software we don't have access to: http://www.whatsbestforum.com/showthread.php?3320-Comparison-of-Double-Bass-Array-to-Sound-Field-Management-Overview
Scroll down to "SFM".

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post #7673 of 11894 Old 12-30-2013, 02:56 PM
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Ok, hopefully this is the right place.

 

So confused on REW - read the manuals, threads, etc.

 

Have a UMM-6 Calibrated Mic with HDMI out on laptop to Onkyo 809.

 

This is my first sweep...well 20th, but still 1st day.

 

First issue is I keep getting LOW LEVELS when I test level prior to the sweep, even running at +1 on the AVR.

 

Then I have no idea what the heck is going on ....not even sure what I am looking at.  If I should post this somewhere else, just yell.  Perhaps my low level issue is messing up stuff ?  All I know is it does not look like anyone else's data.



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First of all, please post a valid measurement graph. I'm not sure what you did, but the vertical scale on the left side of the graph is not visible. Make sure you conduct a full measurement, from 15Hz to 20.000Hz. Then apply smoothing to make the graph more readable, use 1/6 smoothing. To post a graph, click on the small camera icon in the upper left part of the screen, and include the legend in the screen shot. After the new graph is posted, we can see a bit more of what is going on.

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post #7675 of 11894 Old 12-30-2013, 05:21 PM
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Ok, first of all here is my error....not sure what to do about this.

 

 

Then attached is my sweep - as requested above...seems to actually make more sense.  Maybe I was just unsure and all is fine ?  Expect for that error on start up.

 



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Regarding the low level, check the level in Windows Recording Device--it should be 100%.  The Guide shows where to look.

 

I asked for 15-20,000Hz and you posted a graph that shows 10-500Hz. 


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post #7677 of 11894 Old 12-30-2013, 06:02 PM
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Regarding the low level, check the level in Windows Recording Device--it should be 100%.  The Guide shows where to look.

 

I asked for 15-20,000Hz and you posted a graph that shows 10-500Hz.

Ok, I thought I read that it should be at 33% - which is what I thought it was, I will double check.  But that might explain the low level.

 

I ran the sweep right, but I just was not displaying it correct, is this better ?

 

As a side note, my mains are crossed at 80 and my three subs (RW-12d) seem to be running a bit hot, would you agree?

 

Thanks for helping out of course.

 



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post #7678 of 11894 Old 12-30-2013, 06:49 PM
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The measurement presentation is correct now, thanks for following up. You are correct, the subs seem to be running a bit hot. Otherwise, the response above the crossover looks to be OK. Whether you keep the subs running hot is your preference. Congratulations on your progress so far.

Next step, you might consider publishing one of the graphs that show how the bass resonance looks, i.e. a waterfall. Check the guide for instructions.

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post #7679 of 11894 Old 12-30-2013, 07:06 PM
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The measurement presentation is correct now, thanks for following up. You are correct, the subs seem to be running a bit hot. Otherwise, the response above the crossover looks to be OK. Whether you keep the subs running hot is your preference. Congratulations on your progress so far.

Next step, you might consider publishing one of the graphs that show how the bass resonance looks, i.e. a waterfall. Check the guide for instructions.

 

OK, I love progress !!

 

I think I will play with the sub trim, just a bit...then watch a few movies.  Anyways...during the movies I sometimes had a hard time hearing the dialog...perhaps too much in the bass range.

 

Now on to the water...does this look right?  Honestly I have not quite figured out what I should be looking at yet.

 



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post #7680 of 11894 Old 12-30-2013, 07:13 PM
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OK, you get an "A" for effort, but only a "C" for following the guidelines.   The waterfall should show 15Hz-300Hz.  Having said that, the waterfall shows problems in the lower frequency range, which is to be expected.  Do you have any treatments in your room?


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