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step response is a important part to show speed of speaker that is good enough for ITD. See measures

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markus

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@bennybbbx You're searching in all the wrong places. Sound stage width (ASW, spaciousness and envelopment) in two speaker stereo reproduction is largely a function of the speaker's room interaction. Binaural effects can be observed at times. The Lipshitz paper explains why stereo and binaural are not the same.

You should also check these 2 Keele papers for perspective and experimentation:
 
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bennybbbx

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@bennybbbx You're searching in all the wrong places. Sound stage width (ASW, spaciousness and envelopment) in two speaker stereo reproduction is largely a function of the speaker's room interaction. Binaural effects can be observed at times. The Lipshitz paper explains why stereo and binaural are not the same.

I look on it, but sound stage and spacious is only a large room interaction if you sit far from the speaker. I use my JBL 104 BT 45-50 cm, in nearfield. I have measure of RT60 decay from 1 meter and 50 cm away from speaker. when measure at 50 cm it reduce alot room reflections. in my measure i have the volume of speaker same and i get then less level on microphone. to have same level on microphone i need add volume 6 db. then it get even more worse. https://www.audiosciencereview.com/...re-coaxials-so-rare.26915/page-12#post-991037 I hear amazing wide soundstage. my 17 qm room can not produce a concert reverb. So i come to the conclusion directivity of a speaker is does not create concert hall reverbs or reverbs of large rooms that sound good. when you have a speaker with lots directivity it happen that only your room reverb is mixed more to music. but it sound not as a good reverb from the record of music. thats not real. also when make music mono upto 460 hz then the room feeling from large concert hall is lost. so this is another fact, that tweeter directivity is not so important, and speakers have all wide directivity upo 460 hz. thats the reason wy the brain use ITD the phase to recognize direction i think because on low frequency the direction can very bad hear with level diffrence because sound source are always wide on 460 hz

here is video that show how it sound in mono upto 460 hz. the room size get very small then https://www.audiosciencereview.com/...for-itd-see-measures.28585/page-2#post-996188

EDIT: on your link this is only a preprint. preprint can everbody do. and if it since 1986 in preprint state, then other scientist do not conform to this

A preprint, also known as the Author’s Original Manuscript (AOM), is the version of your article before you have submitted it to a journal for peer review.

What is a preprint server?​

Preprint servers are online repositories which enable you to post this early version of your paper online.


I can also do a preprint and upload it to the server about my theorie with the few stereo wide= slow stepresponse :D
maybe the journal buy 100 speakers and verify with the measured step responses if there is a connection . i know that the few speakers i have test are not enough. so more should verify it
My english is not good and i can this not translate in google so i can also not look if there is something i did not know

I see only in the headlines he write nothing about interaural delay hearing and stereo recognize. the interaural crosstalk(about thie he write) is maybe not so much relevant on low frequency when hear ITD. on real sounds in a room you too have lots intraural crosstalk and you can recognize good. for example when you stand near a wall and the soundsource is 5 meter away but the wall only 10 cm.

I have my speakers 80 cm distance left to right and the JBL have a amazing wide soundstage. wider as headphone. the kali is very small much smaller as headphones.
 
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dominikz

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I mean this diagram and i have add the lines of the 2.8 ms i mean.
This is due to the high-pass filter at 15Hz (so similar to e.g. a good subwoofer's low frequency limit). If you put the high-pass filter at a higher frequency, this 'decay time' will decrease, as also illustrated here:
index.php

We see from all this that e.g.
1) without high-pass (so frequency response flat down to 0 Hz / DC) the step function never returns to 0% - i.e. we have an ideal step function,
2) with high-pass at 15Hz it takes 2,8ms to return to 0%, and
3) with high-pass at 100Hz it takes ~0,45ms to return to 0%.
Note from this that the lower the high-pass frequency, the longer the "decay" is, and consequently the closer the resulting filtered function will look to the ideal step response. This basically means that the 'longer it takes' for a loudspeaker's step response to go from 100% to 0%, the lower in frequency the loudspeaker plays. This is all perfectly predicted from Fourier transform and linear systems theory.

Since no real loudspeakers can play down to 0 Hz (DC) we will always see this 'decay' and oscillation in measured step responses, as @KSTR explained.

and thanks for posting the JBL 305 step response. the without DRC left measure is without any EQ ?. it look slower but in compare to kali the time the level have around 90% look much fewer on your step response. maybe this is bad when the step response is much curved as from the Kali and have no sharp edge.
The black line is without any EQ, correct. Also no smoothing/gating applied there.
Your measurements look like some kind of smoothing is applied somewhere - maybe it is worth checking that - and as if they may also possibly contain very early reflections (due to your measurement methodology), which will make the measurement non-time-invariant (so not LTI) and therefore unfortunately make it invalid for this kind of analysis.
but it is still strange wy i get such a much smaller step response with the headphone correctet and LP 1.2 khz. the FR look very linear from bass until crossover freq come.
As explained by @ctrl, unfortunately the way you are measuring headphones is also causing attenuation of low frequencies, which of course affects how the corresponding step response looks. If you measured the same pair of headphones with e.g. a dummy head you would definitely get a very different (and more correct) frequency and step responses. Unfortunately this alone makes it difficult to compare the measured responses and draw conclusions from them.

Let me give you another example how well the theory explains the step response shapes from the frequency response, I did the following test:
  • I have an in-room on-axis measurement of the LSR305 taken at 50cm from tweeter, first significant reflection was 4,8ms after initial pulse so the first few ms are reasonably representative of the loudspeaker's anechoic on-axis impulse or step response
  • Checked the JBL LSR305 datasheet to find that the crossover is implemented as a LR4 filter at 1725Hz and that 41Hz is the -10dB point (48Hz at -3dB).
    • The woofer therefore plays from 41Hz (-10dB) to 1725Hz
    • The tweeter play from 1725Hz onward
  • Based on this I took the ideal step response (0-96kHz bandwidth) and applied an BU8@48Hz high-pass filter and LR4@1725Hz low-pass filter to create an idealized representation of the woofer in LSR305.
  • Then I applied an LR4@1725Hz high-pass filter and BU8@22kHz low-pass filter to the ideal step response to create the idealized representation of the LSR305 tweeter response
  • Lastly I used the REW 'trace arithmetic' A+B function to sum the simulated ideal 'woofer' and 'tweeter' responses to get a representation of the complete simulated ideal LSR305-like loudspeaker
Here's how that looks in the frequency domain:
JBL LSR305 - measured in room vs ideal simulated response (frequency domain).jpg

Similar but also quite different in some ways, at least at first glance - note that in the 'real' LSR305 measurement there are room reflections and modes, especially affecting the LF. If you look at the LSR305 quasi-anechoic measurement you will see that the actual LF extension is really close to the above simulation:
JBL LSR305 - simulated ideal loudspeaker vs quasi-anechoic on-axis measurement.jpg


Now let's look at the same in-room measurement vs simulation in the time domain (step response):
JBL LSR305 - measured in room vs ideal simulated response (time domain).jpg

Amazingly similar in many ways, right? :)
As you can see, even this grossly over-simplified simulation of a loudspeaker (just band-limiting an ideal step function) vs a real measurement of the loudspeaker shows a lot of similarities, and reinforces the principles that I (and others) were trying to explain before.

Related - notice that in REW you can import a pure impulse response, and based on that REW will display the corresponding frequency (magnitude+phase) response, as well as the step response.
This is another clue that they all show the same data, just presented differently (and the mathematical process that converts between them is called the Fourier transform) :) As explained before, from knowing the frequency response (magnitude+phase) you can calculate the step or impulse response (and vice-versa). It also means that two identical frequency responses (magnitude+phase) will have an identical step response.

I understand Linear superposition and i undersand what you want say. frequency and driver have influence of the step response. I agree to this. But this is no forumula with 2 unknown parameter because the Frequency response is measure too and a software can calc step response with normalize FR to better compare. or just use a 100 hz 24 db highpass for all speakers, so the bass range is not so low. I understand that in Bass range small and large speakers are much diffrent in FR. this have a little influence of the fall time of the step response.

here you can see much diffrent FR of the JBL done with EQ in Bass Range. but the fall/rise time from 20% to 20% level increase only a little from 580 µsec to 650 µsec (this are 12%) with this much diffrent Bass frequency change. the kali step response 20% to 20% time need 1440 µsec but have not so much bass as the JBL with the EQ. so because of the kali bass there need much shorter step response, and so conclusion is the driver is very slow.
EDIT: the JBL measure in compare at 1.5 cm. because the room have very less influence it can give much bass. because its coaxial the tweeter is see too in FR and step response
View attachment 169839View attachment 169840

so i think the step response of a speaker is important to see. if you like it more, then can ignore the fall time and show only the raise time. impulse response i think not usefull when test complete speakers. because in a impulse response it is hard to see which is the raise and fall time of the mid/bass. or maybe need see the impulse response of bass/mid or mid only to see if it is good for ITD
View attachment 169838

Or can somebbody explain how i can see on the JBL and kali and headphone impulse response compare which is faster ?????. i can only see the kali look slow. but the headphone look much slower as jbl but it is not
It should hopefully be clear from the explanations and examples so far that the 'rise time' will largely depend on the high-frequency content of the measured response. This will of course be different between different woofers due to different crossover frequencies, and especially compared to headphones with their full-range drivers.
To get comparable results you'd need to make sure that the low-pass filters you are using to level the playing field really remove an equal amount of high-frequency content in all cases.
Also, you'd need to make sure that your response measurement procedure is creating comparable results in the first place. Unfortunately this will not be the case if you're measuring loudspeaker woofers in extreme nearfield and comparing that to an unsealed headphone measurement (without a headphone measurement jig/dummy head) - neither of those two methods will generate good reference measurements for either case, and especially not to compare between them.
However if you put all necessary controls in place to make sure the frequency responses are comparable, you will see that the step responses will in the end become very similar-looking as well :) as I've illustrated above on the LSR305 example.
EDIT: Though I'd still be reluctant to compare headphone measurements to loudspeaker measurements. Due to the nature of headphone measurements (which will include very early reflections within the cup and ear canal) it would be easy to miss important controls and come to wrong conclusions.
I look on it, but sound stage and spacious is only a large room interaction if you sit far from the speaker. I use my JBL 104 BT 45-50 cm, in nearfield. I have measure of RT60 decay from 1 meter and 50 cm away from speaker. when measure at 50 cm it reduce alot room reflections. in my measure i have the volume of speaker same and i get then less level on microphone. to have same level on microphone i need add volume 6 db. then it get even more worse. https://www.audiosciencereview.com/...re-coaxials-so-rare.26915/page-12#post-991037 I hear amazing wide soundstage. my 17 qm room can not produce a concert reverb. So i come to the conclusion directivity of a speaker is does not create concert hall reverbs or reverbs of large rooms that sound good. when you have a speaker with lots directivity it happen that only your room reverb is mixed more to music. but it sound not as a good reverb from the record of music. thats not real. also when make music mono upto 460 hz then the room feeling from large concert hall is lost. so this is another fact, that tweeter directivity is not so important, and speakers have all wide directivity upo 460 hz. thats the reason wy the brain use ITD the phase to recognize direction i think because on low frequency the direction can very bad hear with level diffrence because sound source are always wide on 460 hz

here is video that show how it sound in mono upto 460 hz. the room size get very small then https://www.audiosciencereview.com/...for-itd-see-measures.28585/page-2#post-996188

EDIT: on your link this is only a preprint. preprint can everbody do. and if it since 1986 in preprint state, then other scientist do not conform to this




I can also do a preprint and upload it to the server about my theorie with the few stereo wide= slow stepresponse :D
maybe the journal buy 100 speakers and verify with the measured step responses if there is a connection . i know that the few speakers i have test are not enough. so more should verify it
My english is not good and i can this not translate in google so i can also not look if there is something i did not know

I see only in the headlines he write nothing about interaural delay hearing and stereo recognize. the interaural crosstalk(about thie he write) is maybe not so much relevant on low frequency when hear ITD. on real sounds in a room you too have lots intraural crosstalk and you can recognize good. for example when you stand near a wall and the soundsource is 5 meter away but the wall only 10 cm.

I have my speakers 80 cm distance left to right and the JBL have a amazing wide soundstage. wider as headphone. the kali is very small much smaller as headphones.
ITD is one of several psychoacoustic mechanisms that humans use to localize sounds around us. To my knowledge there is no direct relation between the minimum audible interaural time delay value and the required rise-time of a loudspeaker's step function for good stereo width in the way which you are proposing. If a loudspeaker reproduces a transient, the sound will almost always reach one ear a little bit later that the other ear - that is ITD. This happens in the exact same way regardless whether the source (loudspeaker or something else) reproducing the sound has a 'slow' or 'fast' step response, so it should not be relevant in this context.

Anyway, hoping this wall of text might be interesting (or even useful) to some :)
 
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bennybbbx

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This is due to the high-pass filter at 15Hz (so similar to e.g. a good subwoofer's low frequency limit). If you put the high-pass filter at a higher frequency, this 'decay time' will decrease, as also illustrated here:

oh, thanks alot this explain it. But wy should use a high pass filter of 15 hz before when measure the step response ?. which db per octave the HP filter use ?. a 15 hz low pass filter do horrible phase shifts upto 200 hz and slowdown the speaker system decay time of course. so measure step response with a HP filter before is bad i think.

see screenshots I have the t.racks mini dsp and this can show the phase of the filters . 19 hz is lowest i can get and 24 db per octave max. you can see it do lots phase shifts and i think measure step response with a HP Filter before is not usefull it change step response much because it have in % much influence as can see in screenshot. because the phase shift of the HP filter have so much influence the speakers look more simular. I think thats fake.

please measure without HP filter your JBL.

i do only screenshots of the BW butterworth filters. the other filters this DSP have change only a little. most important is the db /octave. if use filters with more db /octave this increase even more horrible

phase HP 19 hz filter 6 db.jpg
phase hp 19 hz filter 12 db.jpg


phase hp 19 hz filter 24 db.jpg





ITD is one of several psychoacoustic mechanisms that humans use to localize sounds around us. To my knowledge there is no direct relation between the minimum audible interaural time delay value and the required rise-time of a loudspeaker's step function for good stereo width in the way which you are proposing. If a loudspeaker reproduces a transient, the sound will almost always reach one ear a little bit later that the other ear - that is ITD. This happens in the exact same way regardless whether the source (loudspeaker or something else) reproducing the sound has a 'slow' or 'fast' step response, so it should not be relevant in this context.

Anyway, hoping this wall of text might be interesting (or even useful) to some :)

when nobody that can hear ITD do tests as i do without the 15 hz highpass filter, then of course nobody can notice it. ;)
 

dominikz

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oh, thanks alot this explain it. But wy should use a high pass filter of 15 hz before when measure the step response ?. which db per octave the HP filter use ?. a 15 hz low pass filter do horrible phase shifts upto 200 hz and slowdown the speaker system decay time of course. so measure step response with a HP filter before is bad i think.

see screenshots I have the t.racks mini dsp and this can show the phase of the filters . 19 hz is lowest i can get and 24 db per octave max. you can see it do lots phase shifts and i think measure step response with a HP Filter before is not usefull it change step response much because it have in % much influence as can see in screenshot. because the phase shift of the HP filter have so much influence the speakers look more simular. I think thats fake.

please measure without HP filter your JBL.

i do only screenshots of the BW butterworth filters. the other filters this DSP have change only a little. most important is the db /octave. if use filters with more db /octave this increase even more horrible

View attachment 170049View attachment 170050

View attachment 170051






when nobody that can hear ITD do tests as i do without the 15 hz highpass filter, then of course nobody can notice it. ;)

Sorry, but you misunderstood. JBL was measured without any high-pass filter. The diagram with the 15Hz high-pass filter just shows how band-passing an ideal step function to human-hearing range impacts the step response.
May I suggest to please read again my previous posts (which also show that high-passing a signal *reduces* the 'decay time' in the step response, not increase it).
 
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bennybbbx

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Sorry, but you misunderstood. JBL was measured without any high-pass filter. The diagram with the 15Hz high-pass filter just shows how band-passing an ideal step function to human-hearing range impacts the step response.
May I suggest to please read again my previous posts (which also show that high-passing a signal *reduces* the 'decay time' in the step response, not increases it).

in your last measure you filter to 48 hz HP for create a ideal speaker. but your measure of step tesponse is with room impact and much reduced bass which make your step response shorter.

When you compare with a ideal speaker you better measure the step response 1.5 cm away from woofer. this give better bass because room influence is reduce alot.(you can hold microphone in hand so you can do easy and quick. it give no important changes in low freq.only when want measure more than 5 khz better us a stative. need only woofer/Mid measure upto 2 khz) .

in the measure of your JBL can see at 80 hz it have around -5.5 db (i use 85 db as 0 db). at 60 hz it have much less.

I try measure with 19 hz HP filter and without. because i need bass boost correction, this 19 hz Filter bring better phase and faster step response. so it seem good when add a Low HP filter to correct the phase of bass boost low shelf EQ. see phase of my speaker correction. and step get around 50 µsec faster with only reduce the phase shift tzhat is add with bass boost Low shelf EQ
the frequency of EQ setting i use currently. i have EQ settings for 1/2 octave smoothing and correct this and i use it currently and compare with music i hear which i like more 1/1 smooth correct or 1/2 smooth correction

frequency
eq settings.jpg


the phase display of EQ setting with HP filter 19 hz BW 24
phase with EQ and HP 19.7.jpg


same EQ but without HP filter
JBL 104 phase with EQ.jpg


and the compensate less phase shift with the HP 19 hz BW 24 bring better step response of around 50 µs


step response compare with 19 hz HP.jpg
 

Shazb0t

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Haven't you figured out that you're wrong yet?

So many explanations here of why and it seems like you're set on never working it out.
 
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bennybbbx

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Haven't you figured out that you're wrong yet?

Wy are here the people so against show step respons in tests and want tell they are useless ?. on stereophile they show step responses on other sites too. but steeophile show near only overpriced speakers tests. have you read all my posts and measures see ?. I show that a big bass enhance only change the step response 12%. but the kali step response is over 200% longer. there are many more slow speakers with large bass/mid. if it is now 190% or 210% with diffrent eq is this really important ? . i notice only that all speakers with slow step response sound not good in stereo width.
I can not see 3D. i do nothing tell about 3D television. I can save money and need no 3D.
it is also usefull to know which people can hear ITD. when people not hear ITD they should not judge over me because they hear diffrent.
 

markus

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Wy are here the people so against show step respons in tests and want tell they are useless ?. on stereophile they show step responses on other sites too. but steeophile show near only overpriced speakers tests. have you read all my posts and measures see ?. I show that a big bass enhance only change the step response 12%. but the kali step response is over 200% longer. there are many more slow speakers with large bass/mid. if it is now 190% or 210% with diffrent eq is this really important ? . i notice only that all speakers with slow step response sound not good in stereo width.
I can not see 3D. i do nothing tell about 3D television. I can save money and need no 3D.
it is also usefull to know which people can hear ITD. when people not hear ITD they should not judge over me because they hear diffrent.
"I" = "interaural" = "between the ears". It's not related to how "fast" a speaker is.
What you have observed in the step response is largely just speaker bandwidth. Step response is the wrong metric for what you're interested in.
 
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dominikz

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in your last measure you filter to 48 hz HP for create a ideal speaker. but your measure of step tesponse is with room impact and much reduced bass which make your step response shorter.

When you compare with a ideal speaker you better measure the step response 1.5 cm away from woofer. this give better bass because room influence is reduce alot.(you can hold microphone in hand so you can do easy and quick. it give no important changes in low freq.only when want measure more than 5 khz better us a stative. need only woofer/Mid measure upto 2 khz) .
Unfortunately your conclusion here is incorrect due to several reasons:
  • While I did measure in-room, if you read again the description in my previous post, you will see that I made sure there were no significant reflections in the first 4,8ms after the direct sound - so the part of the step response I was showing (first few ms) is indeed anechoic in practice.
    The FR view on the other hand contained these reflections since I didn't show a time-gated measurement, which in turn affects how the bass is presented there. I understand that this can be confusing, but it is really important to understand what LTI means to be able to interpret these kinds of measurements. Room reflections add a non-time-invariant element to the measurement (i.e. makes the measured response non-LTI) and care needs to me taken how the measurement is interpreted.
  • Measuring the woofer nearfield will indeed attenuate room reflections, but will not capture port contribution of a bass reflex loudspeaker, so cannot show the entire low frequency response - this of course would affect the step response.
  • Notice that the measurements I did match very well with the idealized model. This is a clue that my methodology was indeed OK :) More evidence supporting this will be shown in a moment. :)
in the measure of your JBL can see at 80 hz it have around -5.5 db (i use 85 db as 0 db). at 60 hz it have much less
As explained, this is due to room reflections - but since reflections are not time-invariant (by definition), you cannot use LTI principles in the way you're attempting to do here. This reduction in bass happens when the reflected sound hits the microphone, which simply doesn't happen yet in the first few ms of the step response shown. Note again that the first 4.8ms of the step response are relatively reflection-free, and would therefore look the same even if I measured in a real anechoic chamber.

To provide more evidence of this, I will now show the step response of a full quasi-anechoic measurement of the same loudspeaker vs the idealized model of it. A quasi-anechoic measurement is a nearfield port measurement scaled and summed with a nearfield woofer measurement, then baffle-step corrected, and lastly spliced with a time-gated (anechoic) far-field measurement of the loudspeaker. This results in a fully-anechoic (reflection-free) measurement of a loudspeaker, comparable to what could be measured in an anechoic chamber (with some caveats, but irrelevant here).

Here's the frequency domain:
JBL LSR305 - simulated ideal loudspeaker vs quasi-anechoic on-axis measurement (frequency doma...jpg

And here's the step response for the same measurement vs idealized speaker:
JBL LSR305 - simulated ideal loudspeaker vs quasi-anechoic on-axis measurement (time domain).jpg

And a zoomed-out view to show there really are no reflections visible (i.e. proof that it is indeed an anechoic response):
JBL LSR305 - simulated ideal loudspeaker vs quasi-anechoic on-axis measurement (time domain, z...jpg

As you can see, this again shows that the theory holds and that my methodology was OK. :)

I try measure with 19 hz HP filter and without. because i need bass boost correction, this 19 hz Filter bring better phase and faster step response. so it seem good when add a Low HP filter to correct the phase of bass boost low shelf EQ. see phase of my speaker correction. and step get around 50 µsec faster with only reduce the phase shift tzhat is add with bass boost Low shelf EQ
the frequency of EQ setting i use currently. i have EQ settings for 1/2 octave smoothing and correct this and i use it currently and compare with music i hear which i like more 1/1 smooth correct or 1/2 smooth correction

frequency
eq settings.jpg


the phase display of EQ setting with HP filter 19 hz BW 24
phase with EQ and HP 19.7.jpg


same EQ but without HP filter
JBL 104 phase with EQ.jpg


and the compensate less phase shift with the HP 19 hz BW 24 bring better step response of around 50 µs


step response compare with 19 hz HP.jpg
As explained and demonstrated before, adding a high-pass filter to a signal will indeed shorten the 'decay time' of a step response, but this actually makes the step response less accurate - you're removing bass energy, and an ideal step response signal has a lot of bass energy (down to 0 Hz / DC, in fact). This can never be replicated in practice, but the lower in frequency a loudspeaker system can play, the closer you will get to the ideal (i.e. step response 'decay time' gets longer). Please review again my previous posts for examples of this.
Wy are here the people so against show step respons in tests and want tell they are useless ?. on stereophile they show step responses on other sites too. but steeophile show near only overpriced speakers tests. have you read all my posts and measures see ?. I show that a big bass enhance only change the step response 12%. but the kali step response is over 200% longer. there are many more slow speakers with large bass/mid. if it is now 190% or 210% with diffrent eq is this really important ? . i notice only that all speakers with slow step response sound not good in stereo width.
I can not see 3D. i do nothing tell about 3D television. I can save money and need no 3D.
it is also usefull to know which people can hear ITD. when people not hear ITD they should not judge over me because they hear diffrent.
I'm not "against showing step responses". The step response can a useful alternative view of the data, of course. It is just a matter of correct interpretation of what it shows :) I'm hoping my posts in this thread can be a useful starting resource for this.:)

EDIT: Crossed-out the sections incorrectly stating reflections make the system non-LTI. Thanks @markus for the correction!
 
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markus

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it is really important to understand what LTI means to be able to interpret these kinds of measurements. Room reflections add a non-time-invariant element to the measurement (i.e. makes the measured response non-LTI)

Don't want to open another can of worms here but room response measurements including reflections are still linear, time-invariant (LTI), i.e. the output can be calculated from any input and impulse response.
 

dominikz

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Don't want to open another can of worms here but room response measurements including reflections are still linear, time-invariant (LTI), i.e. the output can be calculated from any input and impulse response.
Thanks for the correction - indeed. I'll add corrections to my post to reflect this. However I hope you agree that this in principle doesn't impact the rest of the analysis and explanations.
 
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bennybbbx

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"I" = "interaural" = "between the ears". It's not related to how "fast" a speaker is.
What you have observed in the step response is largely just speaker bandwidth. Step response is the wrong metric for what you're interested in.

of course you can tell me which is better that klippel can show to see how fast the midrange speaker ist. jbl 104 and kali lp6 are testet here. on which parameter you can see that the kali have very few stereo width and the JBL is very good ?. I do a audio example with reverb. play with same filter at 1.5 khz. 1 is sample rate 11 khz 1 is sample rate 44 khz. the version with 11 khz sample rate should sound same as the version with 44 khz if the speed of the mid range is not important. right ?. but i hear clear that the 11 khz version sound strange in room and stereo image. when play only 1 channel mono this can not hear. that the 11 khz sound so worse is because 11 khz sample rate can not produce the phase exact at least at 40 µsec . 11 khz is period time of ~ 90 µsec. so when use sample rate of 11 khz it can the phase not good enough reproduce. and so you get stereo loss. can hear on headphone too. or do you think they sound same ?
filter for hear test.jpg
 

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markus

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Thanks for the correction - indeed. I'll add corrections to my post to reflect this. However I hope you agree that this in principle doesn't impact the rest of the analysis and explanations.
Sure. I admire your patience in what looks like a case of "you can lead a horse to water but you can't make it drink" ;)
 

tifune

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I can't gauge it, are your statements meant as satire or is this an attempt at trolling?

After many people in the neighboring thread have pointed out to you, over weeks, the problems with the evaluation of the step responses over and over again, you post again (I can't say it any other way and apologize in advance for it) such crap.

Dunno man, he could be hustling us all. I'm a firm believer in the maxim "the best way to find the right answer to any Q is to post the wrong answer on the internet."
 
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bennybbbx

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this measure


Now let's look at the same in-room measurement vs simulation in the time domain (step response):
View attachment 169987

and this new

And here's the step response for the same measurement vs idealized speaker:
View attachment 170301

look identical. it reach 20% at 1 ms, 10 % at 1.2 ms. only the resolution is diffrent. you need subtract 200 µsec so your JBL need from 20% to 100% to 20% 1 ms but anyway you confirm that the JBL Bass/ mid is fast. no wonder, it is only 5 inch. We talk about to see slow 6.5 inch or 8 inch speakers. your anchor version FR have much more bass, but you see the step response is not noticable diffrent.

look the LP 6 step response in compare. noticable longer to reach 20%. need 1.4 ms the FR is not better because my measure ignore the bassport. the 1.5 cm measure is correct and good because we want only know the speed of the mid range. the step response get shorter when use a HP. so to measure it is possible to use a HP filter of 100 HZ and speakers mid range is test too. and there is not so much FR diffrence between 5 inch to 6.5 inch or 8 inch speakers. because all speakers from 4 inch can play 100 hz +-3 db .Also when compare step responses can not perfect compare a 5 inch speaker with a 6.5 inch speaker. or a 5 inch speaker with 8 inch speaker. bestter compare speakers with same inch. In your other measure of a revel i ask for step response of it. because it have a 6.5 inch woofer /mid. this can better compare with kali

but look at the kali it need much longer and have less bass(because of bass port not measures when distance is 1.5 cm)
kali lp 6 step response.jpg


maybe you can do the hear test with 11 khz and 44 khz sample rate in my previous post. if you hear a diffrence in stereo width and room feeling.
 
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bennybbbx

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Dunno man, he could be hustling us all.

I dont know what you mean. i put text in german google translate and it output Keine Ahnung, er könnte uns alle bedrängen. now i translate it back to english this is the output I don't know, he could harass us all.

maybe i explain it in german so it is more understandable and somebody can translate. for physical or technical stuff translators work wrong.

Ein Bass/mid Treiber der 5 khz -3 db schafft der braucht 200 µsec um 70% des Pegels zu erreichen. wenn er schneller als 200 µsec wäre, dann würde er auch höhere frequenzen schafffen. Menschen die ITD hören können, interpretieren aber zeitunterschiede ab 20 µsec für die Schallrichtung und räumliche Darstellung von Frequencen unter etwa 1.5 khz. 1 khz hat eine Periodenzeit für 1 Halbwelle von 500 µsec.

linker und rechter Lautsprecher geben bei stereo Musik unterschiedlichen Pegel und Frequenzen aus. so kann es passieren dass der linke kanal Pegel in einer zeit von 500 Microsekunden sich kaum ändern und auf einem peak bleibt. da erreicht der lautsprecher den Peak also ohne Verzögerung. Der rechte Kanal muss seinen wert ändern. dadurch ändert sich dann automatisch die frequenz der Lautsprecher(links rechts) unterschiedlich. hat man einen breibänder mit hochtöner zusammen oder ohne hochtöner, dann ist der viel schneller im mid bereich und erreicht die pegel für den linken und rechten speaker mit 3-4 mal geringerer verzögerung. Daher vermutlich sind viele der Meinung dass Breitbänder besseres stereo image bringen.

Dazu kommt noch die verzögerung eines steilflankigenen LP filter. weil linker und rechter kanal mit unterschiedlicher frequenz auch spielen, verschiebt sich die Verzögerung zusätzlich zwischen links und rechts. Daher denke ich klingen auch Steilflankige LP filter schlecht. die kali hat wahrscheinlich 48 db . Hab in dem DSP nur nen 24 db LP. aber schon bei 500 hz macht der massive phasenserschiebung. rechne ich richtig ? 500 hz 45 grad wären dann :500 hz sind 2000 µsec Periodenzeit /360 * 45= 250 µsec. was zuviel für gutes ITD ist. die JBl 104 hat nur 6 db Filter. bei Coax Systemen geht das besser mit flachen LP Filtern
LP 1.5 khz 24 db.jpg
LP 1.5 khz 6 db.jpg
 
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dominikz

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this measure



and this new


look identical.
Of course they do - that is exactly the point that I was arguing from the start and one that is completely expected. :) Both of these are also very similar to the idealized model I was showing - which should tell you that the low/high frequency extension (and respective slopes) of a loudspeaker driver define the bulk of the basic shape of the corresponding step response, including its 'rise time' and 'decay time' (or its "speed", as you like to say).
it reach 20% at 1 ms, 10 % at 1.2 ms. only the resolution is diffrent. you need subtract 200 µsec so your JBL need from 20% to 100% to 20% 1 ms but anyway you confirm that the JBL Bass/ mid is fast. no wonder, it is only 5 inch. We talk about to see slow 6.5 inch or 8 inch speakers.
Unfortunately this is again the same incorrect interpretation of the data.
Compared to JBL LSR305 the Kali LP-6:
  • Has a few Hz more low-frequency extension than JBL LSR305 -> which will make the step response 'decay time' longer, and
  • It uses a lower crossover frequency (1500Hz instead of 1725Hz in JBL LSR305) which will make the woofer step response 'rise-time' longer. However, this part of the frequency range is taken-over by the tweeter so nothing is necessarily lost.
If you band-pass the Kali LP-6 woofer the exact same way as it is done in JBL LSR305 the two step responses will become very similar, regardless of driver diameter.
This should be perfectly clear if you take the time to really analyse my previous posts. In my idealized LSR305-like simulation I've managed to get practically the same step response as a real unit without any loudspeaker driver at all :D - just by roughly matching the low-and high-pass filters to be similar to the frequency response of a real LSR305 unit, and applying the filters to an ideally flat transfer function (0-96kHz) / ideal step response.
your anchor version FR have much more bass, but you see the step response is not noticable diffrent
This is also incorrect. In both the in-room and quasi-anechoic measurement there is obviously the same amount of bass output by the loudspeaker because it is the same loudspeaker unit being measured. :D You seem to be misunderstanding the fact that the first few ms of my in-room measurement are anechoic as I've taken care to avoid very early reflections when measuring - this is why the early part of the step response looks the same as the quasi-anechoic one and very similar to idealized simulation.
If we look past the first few ms, the in-room measured step response will look very different as we will start seeing more and more reflections from the room - here's evidence of this as well :
JBL LSR305 step response comparison - In-room measurement vs quasi-anechoic measurement vs ide...jpg

This is exactly why the in-room and quasi-anechoic *frequency responses* look different, and why we sometimes use time-gating in the first place - to remove reflections and get an effectively anechoic response (above a certain frequency)!

look the LP 6 step response in compare. noticable longer to reach 20%. need 1.4 ms the FR is not better because my measure ignore the bassport. the 1.5 cm measure is correct and good because we want only know the speed of the mid range. the step response get shorter when use a HP. so to measure it is possible to use a HP filter of 100 HZ and speakers mid range is test too. and there is not so much FR diffrence between 5 inch to 6.5 inch or 8 inch speakers. because all speakers from 4 inch can play 100 hz +-3 db .Also when compare step responses can not perfect compare a 5 inch speaker with a 6.5 inch speaker. or a 5 inch speaker with 8 inch speaker. bestter compare speakers with same inch. In your other measure of a revel i ask for step response of it. because it have a 6.5 inch woofer /mid. this can better compare with kali
By this logic all subwoofers in the world are "slow", and the best ones (e.g. those that play lowest with significant SPL) are the "slowest". :)
Please refer to posts #29 and #32 for explanations why. Again, what you seem to call "speed" of the mid-woofer is mainly determined by the crossover frequency ('rise-time') and low frequency extension ('decay time').
You should also try to understand that an ideal step function will have infinitely fast rise-time and *no decay at all* - I.e. it stays at 100% forever. This is of course unachievable in practice. However it does mean that a loudspeaker that has a longer step response "decay time" is more accurate, since its step response stays close to 100% for longer. This doesn't make the loudspeaker slower - it just means it is able to play lower frequencies!
but look at the kali it need much longer and have less bass(because of bass port not measures when distance is 1.5 cm)
kali lp 6 step response.jpg


maybe you can do the hear test with 11 khz and 44 khz sample rate in my previous post. if you hear a diffrence in stereo width and room feeling.
Please see above explanations, and I again refer you to posts #29 and #32.
 
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bennybbbx

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Of course they do - that is exactly the point that I was arguing from the start and one that is completely expected. :) Both of these are also very similar to the idealized model I was showing - which should tell you that the low/high frequency extension (and respective slopes) of a loudspeaker driver define the bulk of the basic shape of the corresponding step response, including its 'rise time' and 'decay time' (or its "speed", as you like to say).

I mean the step response of JBL 305 look near same between the room measure and the anechic measure and . the bass frequency of your room measure that reach microphone is much lower as your anechoic measure. so i come to conclusion your screesnhots confirm too that influence of the frequency is not much.

Unfortunately this is again the same incorrect interpretation of the data.
Compared to JBL LSR305 the Kali LP-6:
  • Has a few Hz more low-frequency extension than JBL LSR305 -> which will make the step response 'decay time' longer, and

but i measure the kali 1.5 cm near . the boost of the bass port is lost in the Kali. so it have very few bass in this measure but long step response. your measure are done with bassport.


  • It uses a lower crossover frequency (1500Hz instead of 1725Hz in JBL LSR305) which will make the woofer step response 'rise-time' longer. However, this part of the frequency range is taken-over by the tweeter so nothing is necessarily lost.

what db /octave the JBL 305 use ?. the kali use 48 db/ octave it looks. this slowdown step response too. maybe should ignore the decay time and only look at the raise time. the raise rime is much slower as from your JBL 305. the few hz higher crossover does not explain this large slowerdown
kali 1 meter.jpg


JBL 305 raise time 200 µsec
Kali LP 6 raise time 320 µsec

also the time that the kali begin to decay is much longer as on JBL 305. thats reason i think step response is usefull to detect bad speaker design for ITD and find good. now lets see step responses of 6.5 inch speaker or 8 inch 2 way speakers

EDIT: i have add the REW measure file to kali loopback zip and jbl 104 so you can overlay the kali or jbl 104 stepresponse with your JBL or your other speakers.
 

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