Feature Request: In Overlay Window "Spectrogram Show slice at Time in ms" add

user44455555

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Hello

I think now the Feature in spectrogram show slice at cursor is best to show the truth and detect bad speaker resonances or do room treatment. with this settings. I think when the overlay also allow the show slice at cursor feature, to compare diffrent measure easy
help alot. the spectrogram graphic need not show in overlay. Only a slider to choose the slice time and the time need show.

show modal frequency show room modes. for example: look at the results, there happen peak, that is not on a modal frequency. this show even more if a near field speaker have bad case resonance(if speaker is 3 m, away influence is not so much, but you can be sure, if speaker case resonance and strong room mode is same, it can be also worse) . Maybe the speaker developers and speaker testers test speakers because there are enough as good promoted speakers out that sound worse. So this feature can enhance speaker quality.

The measure is done when have the microphone 2 mm from focal alpha 65 evo back plate in middle. so it is not room influence. the focal have front bassport
I come to the conclusion Dr. Floyd Toole is right in the time he do that. When he say that decay times in small rooms can not measure because in the time he do that, there was only ISO measure code that give in bass additional filter time. but with modern T60m, spectrogram, waterfall code there can trust the decay values. I verify with alogrithmic reverbs.






focal back at 0 ms.jpg


focal back 143 ms.jpg



BTW: I have old measures that show in spectogram no modal frequencies. which rulses must fit that modal frequencies are show ?
 
Here can see the JBL 104 results at ~0 0 ms and 140 ms time. the bass port is on back, I measure in middle below bassport but the back show also port output. it decay much better as the focal. so speaker testers or developers need no laser to measure case resonances. the above graphic is not important to see, only important to see precise results is the below frequency slice at the decay time.

jbl 104 ~0 ms.jpg


at 140 ms the frequency result

jbl 104 140 ms.jpg


there can see the decay in bass is much more equel in the frequency

Now that i see precise decay results that fit what i hear, i open the focal backside and what i find was a scandal. there are 2 parts clue together. tip with the fingers on the bass port top inside let vibrate it very much with decay. it is thin plastic. so i order alubutly if it can reduce the resonance. I did not expect such worse quality, because all testers test the focal as good and it cosat more as a kali or JBL or adam with simular size.

this is look from back of the open focal. the bassport is very long. there is a gap below the bassport, so i hope i can also put alubytl below it(with clue piece.) remove all the screws in front did not help, seem they have clue the bass port on more places, so i can not remove the bass port. I can not measure the thinkness of the plastic bassport rounded rectangle with a caliper. but i guess it is only 2 mm thick. the old focal alpha 64 have a split bass port . this can be stronger.

focal bass port.jpg
 
In the EQ window, Modal Analysis panel enter the room dimensions.

On every new measure i do, room dimensions are set to 3 3 3 also on start rew new. I see in preferences no gui entries to save that. my very old measure when load have 0 0 0 . I change some measures to 3, 4, 2 but i see no solution that the settings are store and use for new measures . How can i store that to use for all future measures ?
 
I let analyze the AI to show how many decay speed it have on problematic room modes. there is lots diffrence between speaker visible. diffrent placement can not explain that. of course on room modes when the case also resonate in this range, then levels get higher. I use old measure with 76 db from here


and AI check if there is diffrence on focal between 66 db and 76 db Level(to simulate weak bass of small speakers). result is the decay at 66 db on the focal is even more slower
45 Hz Decay: 1,0 dB (at 76 db was 2 db)
91 Hz Decay: 9,0 dB ( near same 9,5 dB at 76 db)
Mid/High Decay: 18,0 dB (same as with 76 dB volume)


peak energy time.jpg


energy decay time 0 ms to 144 ms.jpg


so this results confirm that speaker quality is really worse because nobody test it. The AI tell that REW is the only measure software(except the klippel can do that too) that can output precise slices so nobody need buy a klippel to see bad speaker case resonances. I have clue Alubutyl on the focal bassport and it help to reduce some resonances that can see more easy in T60m because it work relative. spectrogram work absolute so to compare easy you need use a AI to get such table as i post to save time.

My desktop is changeable in height, and when i knock on the metal it give a metal ringing tone. same happen with the stative plate when the small JBL are on it. AluButyl also help here. i glue it on the side of desktop metal and below speaker plate. In measurement can not see any changes, but anyway i have it now and cost no additional money

that the bassport ring less with alubbutyl on the focal and is clearly measurable in T60M. I glue 3 2 mn peaces on top of bassport. I have black alubutyl buy. so can not see anything in video. The mts files are 32 upto 51 megabytes large and can also hear the ring is reduce. i use a rubber to hit the bassport. normaly rubber give dull knock noise, but do this on bass port give also higher freq knock noise. so another confirm how worse 350$ speakers(1 speaker only) that are test as good, are build very worse because none of the famous testers test decay time or directivity at 140 ms or peak energy time.

here is the FR you can see in high freq speaker and microphone is for both measures at same position because they differ very few.

focal FR.jpg


and here the RT 60compare. because the bassport is glue inside the focal i can not remove it or the thin plastic of the port maybe break. so i am not able to put Alubutyl on the downside of the bass port. but it have some good enhancements in the 200 hz range. the 180 hz peak is higher now but other are lower

t60m focal.jpg


ADDON:

I notice the grill on the JBL cause this large 350 hz resonance. so i remove the grill and put alubutyl to it. not nice only to show that Problem is mostly speakers in nearfield and not room and how can measure it. so better speakers = better sound . in the following jbl stand on difftrent place than the old measurement. so room mode frequency change but a better damped speaker get better results

REW mdat can download

jbl 104 0  ms.jpg


jbl 104 alubutyl grill 0 ms.jpg


The FR display at 140 ms
jbl 104 140 ms (2).jpg

jbl 104 140 ms alubutyl.jpg


the remopve of the grill in the jbl 104 is easy with a screwdriver. but get it full in is not easy. I press it so it hold. maybe i remove the grill complete, measure are near same without grill.

grill .jpg

jbl 104 grill 2.jpg
 

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Last edited:
Perhaps it would be a better idea—and easier to program—if the time for the SPL reading could also be adjusted within the SPL display? After all, displaying the spectrogram isn't the priority; the goal is simply to view the SPL at a specific point in time in order to observe room and loudspeaker enclosure resonances.
 
which is the setting for highest resolution in spectrogram slices. ? https://www.audiosciencereview.com/...tion-from-october-28-2025.67011/#post-2647340 Here tell Dr. Toole that there need measure with laser vibrometer at same time at diffrent location to show the hearable resonances. but science tell that in bass when wavelength are larger as the speaker enclosure there are no complex patterns. Also a slice animation over time show always the same peaks and valleys . but to show best as can, the highest resolution and windowing i want use and create animations. here i have done animations with headphone and focal . the headphone is only put on desktop table, my hand is put on headphone headband and held the microphone 5-10 mm near headphone. in ASR forum other posts are screenshot of it. and because the time slice show all the time constant resonance frequencies there is no need to measure at same time simulatanious on other locations. this is a gif animation. show from 0 to ~150 ms time slices
sennheiser HD300 pro as reference can see my room is not much noticable problem. :Edit seem the forum allow not to play gif animations. download also not help. i have zip it and upload the animations



sennheisser hd 300 pro.gif




focal much worser,
focal 2 mm.gif


what setting can use to make the resolution highest and smoothing fewest ?. when use rectangular smoothing there is no decay see
 

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The Decay graph might be a better option to view a series of spectral decay traces.

Time and frequency resolution are a trade-off, longer windows have higher frequency resolution and lower time resolution, shorter windows the opposite. Window type has an influence, but Gaussian is a good compromise.
 
The Decay graph might be a better option to view a series of spectral decay traces.

Time and frequency resolution are a trade-off, longer windows have higher frequency resolution and lower time resolution, shorter windows the opposite. Window type has an influence, but Gaussian is a good compromise.

I try the decay graph with newest beta, only when i reduce rise time to 10 ms it show usefull decay. . here can download the headphone measures. https://www.audiosciencereview.com/...rom-october-28-2025.67011/page-2#post-2650886 I use headphone for this test to have same situation with speakers and headphone and same levels . the default settings are not usefull and i see no function to apply the 10 ms rise time setting to all measures easy.
akg 712.jpg
 
The peak energy time work mostly in steps of 0, 15 ms , 31 ms, 46 ms. is it possible that this steps can reduce easy to 4 or 8 ms ?
EDIT: The group delay have better precision but this is on hearing place so much fluctuating. so energy peak time look more realistic

here is a audio test that can hear easy 4 ms delay of the 120 hz wave in compare to 60 hz. this simulate situation of bass play.

Klippel team wrote that can hear also 0.4 ms

Spectral components below 100 Hz contribute to the excitation level of one critical
band


Phase distortion corresponding with a group
delay variation of 0.4 …2 ms within a critical band change the timbre and roughness
of the sound

https://www.klippel.de/fileadmin/klippel/Files/Know_How/Literature/Papers/Loudspeaker%20regular%20signal%20distortion%20caused%20by%20design_part%201_Klippel_Werner.pdf


60 hz 4 ms generator settings.jpg


abx compare 60 hz 4ms .jpg



Dr. Toole say that phase problems can not much hear, but we did not know how he test, which songs he use. On hard compressed HIFI Songs as this, bass have lower low bass level and less transients

but with a mix that play on concerts compression is few and low bass is louder more transients as can hear in such covers

because 60 hz fit perfect to 48000 hz samplerate the zip size is very small. I also add a -4 ms file. this sound in speakers better as 0 ms because speakers have large energy peak delay
 

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Last edited:
Klippel team wrote that can hear also 0.4 ms
I took a test to identify two instruments, a medium-sized drum and a hi-hat. The difference between impacts can be reduced to 1 µs. The 100 µs difference is always detected. 20 µs at 95%. 10 µs at 50%.
This is interesting. But. I read your posts. I can't understand what you get from what you do. Or what goal you are trying to achieve.
 
It doesn't work in steps at all, those effects are coming from your environment, reflections and resonances.

maybe the steps are create from FFT size or window size 16384 say the AI because this fit to 15 ms steps. here a zoom . energy peak time is much more stable as group delay. i only ask if it can maybe easy reduce with diffrent window size or reduce fft size ? this are 2 mm measures, and on both speakers the same steps but the jbl 104 reach not so much delay. but maybe it have less delay as 15 ms.
focal back.jpg

jbl back.jpg
 
I took a test to identify two instruments, a medium-sized drum and a hi-hat. The difference between impacts can be reduced to 1 µs. The 100 µs difference is always detected. 20 µs at 95%. 10 µs at 50%.
This is interesting. But. I read your posts. I can't understand what you get from what you do. Or what goal you are trying to achieve.

did you hear no diffrence in the 4 ms test i upload ?. this huge phase problems bigger speakers have, shift the harmonics and so the waveform inside a bass instrument. bass sound driffent and lush when phase between harmonics differ

resonances is a big problem when speaker get larger. resonances reach only peak after some time. see a swing. it can not reach with the force of a human a high level in 1 cycle. use sveral cycles it reach high level with fewer force

as you can see in above post with the zoom the focal have a delay in peak energy of 46 ms. the jbl 104 only 15 ms. because spinorama show only time at 0 ms.so there are expensive speakers sell that are worse, because reviewers measure it, and speaker developers do not care about it. You can not see the speaker with less or more peak energy delay in bass and spinorama. And of course when pay for a speaker pair 700 $ you want not a speaker that is worser than a 180 $ speaker pair. the jbl 104 have less bass and because of the stronger highpass effekt the jbl 104 should have larger peak energy time as the focal.
 
i notice when use othe color sheme. only the dottet line is steped.

spectrogram.jpg


On other settings wavelet th dottet line is not stepped, but i think it is not correct what can see
wavelet.jpg
 
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