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

[user44455555]

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.

BTW: I have old measures that show in spectogram no modal frequencies. which rulses must fit that modal frequencies are show ?

 

[user44455555]

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.

at 140 ms the frequency result

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.

 

[John Mulcahy]

I have old measures that show in spectogram no modal frequencies. which rulses must fit that modal frequencies are show ?

In the EQ window, Modal Analysis panel enter the room dimensions.

 

[user44455555]

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 ?

 

[John Mulcahy]

On every new measure i do, room dimensions are set to 3 3 3

The default dimensions for new measurements are taken from the room simulator settings.

 

[user44455555]

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

U

Post in thread 'Is there clarity display possible with higher resolution as the T60M ?'

Feb 7, 2026

I have now test my speakers in middle of room on stativ so FR is better. I have done all speakers with microphone distance 1 meter(measured with laser distance measure) to get more science tests. all speakers stand on stative on same pos microphone was not move during all speakers. I use for all measures 4 repetitions and i measure them with 66 db and 76 db with REW rampes Levels. see screenshot. The volume of all speakers i set with check levels verify in REW to 76 db.

The result is the same the most expensive speaker the focal alpha 65 evo is the worst in clarity and T60. the JBL 104...

• user44455555

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)

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.

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

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

The FR display at 140 ms

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.