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My room
Old 2nd October 2013
  #181
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here is a piture of the back room...



Here I can put a wall of Wings behind the soffa and cut of the area of the back room and have the same result of T30 as I linked before in "A different way of treating a room"

But everything has to be practical when treating a ordinary livingroom.

Last edited by Mctwins; 2nd October 2013 at 09:22 AM.. Reason: adding text
Old 2nd October 2013
  #182
NLP
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Ok... so if there is NO absorption, what is the function of this Varitunes "Basabsorbenter": Basabsorbenter ?
Old 10th December 2013
  #183
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Hallo!

Here is measurements of the upstairs room with four Flowerwings on the floors first reflection point. The reflection points has been checkt with mirror and covers the mid and high freq transducers.



Here is before and after measurement ONLY with and without Flowerwings.

ARTA measurements....

Green, with Flowerwings
Red, without Flowerwings







Burst decay, without Flowerwings



BurstDecay, with Flowerwings



Now, REW measurements....

Green, with Flowerwings
Blue, without Flowerwings











ETC





Finally, that nasty floor reflection is gone. Mission completed

Last edited by Mctwins; 16th December 2013 at 09:11 AM.. Reason: Adding two graphs, ETC
Old 12th December 2013
  #184
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Bloody nice room McTwins. Isnt there some too high reflections in your ETC though, prior to 7ms?

And is that a termination of your ISD gap after only 8 or 9ms or so? Am I reading that right?
Old 16th December 2013
  #185
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Quote:
Originally Posted by dodittydada View Post
Isnt there some too high reflections in your ETC though, prior to 7ms?
We, Bobecca and I, don't understand your question. As we see it , there is no high reflectons as you describe. All reflections is below -10dB. Look at the added ETC graphs in post 182.

Quote:
Originally Posted by dodittydada View Post
And is that a termination of your ISD gap after only 8 or 9ms or so? Am I reading that right?
No, there is no termination of the ISD gap per definition because when you go all in with SMT concept you will be in the spaciousness field.

Look here....
https://www.gearslutz.com/board/8213380-post153.html
Old 16th December 2013
  #186
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Here is two exemple of CSD graphs that shows the diffusion in time(=temporal diffusion) down to 200Hz with and without Wings in upstairs room. Exactly as described in the SMT's brochure.

without Flower on the floor



with Flower on the floor



Here is another example https://www.gearslutz.com/board/9455764-post167.html from my downstairs room that shows the effectivness of the Wings and proves that it is an broadband type of diffuser. It alters and evens/stretches out the freq response from 200Hz to 4000Hz. This downstairs room is not as heavely treated as in the upstairs room.

Here we have created two neutrally rooms without any use of visible porous absorber panels and this corresponds to Linkwitz AES paper from 2007 that states.....

"The requirement for full spectral content of the
reflections rules out the use of frequency dependent
absorbers on the room surfaces. The various
commercially available foam or fiberglass panels
absorb predominantly higher frequencies only and
would color the room reflected sound dynamically to
where it no longer can be cognitively separated from
the direct sound"


This is what we hear when we listening to music in both rooms. The sound is more neutral, dymamic, balanced, well defined, and most importantly, we can play loud music for long period of time without getting tired. This is also confirmed when looking at the Burst Decay graphs. It becomes more dense and even out the reflections.

Old 16th December 2013
  #187
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Quote:
Originally Posted by NLP View Post
Ok... so if there is NO absorption, what is the function of this Varitunes "Basabsorbenter": Basabsorbenter ?
This is the function of the Varitunes......

Magico introduced the Q series subwoofers - Page 19

And we totally agree with Stereo point of view here....

I can add this as well......

Magico introduced the Q series subwoofers - Page 20
Old 17th December 2013
  #188
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Quote:
Originally Posted by Mctwins View Post
We, Bobecca and I, don't understand your question. As we see it , there is no high reflectons as you describe. All reflections is below -10dB. Look at the added ETC graphs in post 182.

Ok. I would have thought -10db is not low enough. But hey, if it works for you it's all good.


No, there is no termination of the ISD gap per definition because when you go all in with SMT concept you will be in the spaciousness field.

Look here....
https://www.gearslutz.com/board/8213380-post153.html
Old 17th December 2013
  #189
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Not according to this, I would say that we are well within this standard in both rooms.

Read section 2. Acoustic Parameters. 2.2 Early reflections

http://tech.ebu.ch/docs/tech/tech3276.pdf
Old 17th December 2013
  #190
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Yeah. That paper is certainly the reference, but that figure they quote has always puzzled me. Maybe that's for general listening and broadcast conditions, and the -20db figure bandied about is more desirable for a mixing environment. Anyway I really like your room, nice work.
Old 17th December 2013
  #191
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Quote:
Originally Posted by dodittydada View Post
..... Maybe that's for general listening and broadcast conditions, .....
Yes, many skilled professionals aren't too satisfied with this response (+/-3dB at 1/3 octave smoothing, as defined in paper, even if this is not easy to reach in the small room), and they ask for better. Equal or better response than +/-3dB at 1/24 octave smoothing, below 200Hz (or 300Hz) is more acceptable, as attached results, especially second one, measured two days ago (+/-1.5dB at 1/24 octave smoothing):




Attached Thumbnails
My room-image_5772.jpg   My room-image_2094.jpg  
Old 17th December 2013
  #192
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Boggy,

Nice One !

Though I would say +/- 3db at 1/24 below 200hz is quite difficult to achieve...+/- 1.5db damn sight harder! That's a strict requirement. I think +/- 3db at 1/24 in the low end is an excellent achievement for small room acoustics.
Old 18th December 2013
  #193
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Quote:
Originally Posted by dodittydada View Post
Boggy,

Nice One !

Though I would say +/- 3db at 1/24 below 200hz is quite difficult to achieve...+/- 1.5db damn sight harder! That's a strict requirement. I think +/- 3db at 1/24 in the low end is an excellent achievement for small room acoustics.
Thank you!

I always try to find how far I can go.

Old 18th December 2013
  #194
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Quote:
Originally Posted by boggy View Post
Yes, many skilled professionals aren't too satisfied with this response (+/-3dB at 1/3 octave smoothing, as defined in paper, even if this is not easy to reach in the small room), and they ask for better. Equal or better response than +/-3dB at 1/24 octave smoothing, below 200Hz (or 300Hz) is more acceptable, as attached results, especially second one, measured two days ago (+/-1.5dB at 1/24 octave smoothing):




This is spectacular ... Knowing your work I guess the sonogram is equally impressive, isn't it? Can you give some room details about size and volume percentage of absorbent in relation to the room volume?
Old 18th December 2013
  #195
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Quote:
Originally Posted by G. E. View Post
This is spectacular ...
Thank you very much Gernot.
Quote:
Originally Posted by G. E. View Post
Knowing your work I guess the sonogram is equally impressive, isn't it?
Are you serious? heh A couple of your UBAs are able to make clean spectrogram below 300Hz...
My room-spectrogram.jpg

Quote:
Originally Posted by G. E. View Post
Can you give some room details about size and volume percentage of absorbent in relation to the room volume?
Yes, I will do that:

Before treatment (nearly cube, btw):W401xL421xH379cm volume was 64m3
After treatment: W335xL341xH270cm volume is now 31m3

volume of the treatment is 33m3 (51.6%)

Treatment is not fully porous, it is rather more complex, with wideband membrane resonant absorbers too... But not steel plate type.


Best regards,



Old 18th December 2013
  #196
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Quote:
Originally Posted by boggy View Post
Attachment 376634


Yes, I will do that:

Before treatment (nearly cube, btw):W401xL421xH379cm volume was 64m3
After treatment: W335xL341xH270cm volume is now 31m3

volume of the treatment is 33m3 (51.6%)

Treatment is not fully porous, it is rather more complex, with wideband membrane resonant absorbers too... But not steel plate type.
Just checking now;

This sonogram does not look to be from the same measurement as seen in post 190 since the peaks/dips don´t correlate, and the swing is about 6 dB between around 35 to 200 Hz (so about +/- 3 dB … still excellent result though).

But more interesting: the sonogram indicates an extremely even decay rate for the entire frequency range displayed (up to 300 Hz) of about 66 dB/s … this would result in a decay time of about 0,9 seconds … in a 64 m3 room treated down to 31 m3 ...? That seems very high too me and I suspect something is not right here.
Old 18th December 2013
  #197
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Quote:
Originally Posted by Jens Eklund View Post
Just checking now;

This sonogram does not look to be from the same measurement as seen in post 190 since the peaks/dips don´t correlate, and the swing is about 6 dB between around 35 to 200 Hz (so about +/- 3 dB … still excellent result though).
It is the same room, same treatment, different microphone position.
Quote:
Originally Posted by Jens Eklund View Post
But more interesting: the sonogram indicates an extremely even decay rate for the entire frequency range displayed (up to 300 Hz) of about 66 dB/s … this would result in a decay time of about 0,9 seconds … in a 64 m3 room treated down to 31 m3 ...? That seems very high too me and I suspect something is not right here.
0.9s? What is not right? Can you elaborate more?
Old 18th December 2013
  #198
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Quote:
Originally Posted by boggy View Post
0.9s? What is not right? Can you elaborate more?
A decay time of about 0,9 seconds in a room of that size with that amount of treatment?
Old 18th December 2013
  #199
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Quote:
Originally Posted by Jens Eklund View Post
A decay time of about 0,9 seconds in a room of that size with that amount of treatment?
Couple of questions:
-Where you see 0.9s decay time?
-You pretend to know what I put in 51% of room volume as treatment, and you also think to know why?
-You also tried to imagine what this treatment (you know nothing about) will do in this room, without trying or measurement?
Old 18th December 2013
  #200
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Quote:
Originally Posted by boggy View Post
Couple of questions:
-Where you see 0.9s decay time?
https://www.gearslutz.com/board/attac...pectrogram.jpg

If the room was not heavily treated, the plot would not look like that so I can safely assume that the room is heavily treated, right?
Old 18th December 2013
  #201
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Just to be clear: according to the plot you posted:


From about a 40 dB fall within 600 ms at about 200 Hz = approx. 67 dB/s decay rate = a T60 of about 0,9 seconds.

To about 35 dB fall within about 550 ms at around 80 Hz = approx. 64 dB/s decay rate = a T60 of about 0,94 seconds.


Too me; a 0,9 second decay time in a treated room of that size sounds completely unrealistic: do you not agree?
Old 18th December 2013
  #202
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Quote:
Originally Posted by Jens Eklund View Post
Just to be clear: according to the plot you posted:


From about a 40 dB fall within 600 ms at about 200 Hz = approx. 67 dB/s decay rate = a T60 of about 0,9 seconds.

To about 35 dB fall within about 550 ms at around 80 Hz = approx. 64 dB/s decay rate = a T60 of about 0,94 seconds.


Too me; a 0,9 second decay time in a treated room of that size sounds completely unrealistic: do you not agree?
Here is 60dB spectrogram so you can try to find where is your 0.9s decay:

My room-spectrogram-60db.jpg

And RT60 too:

My room-rt60.jpg

EDIT: You still know nothing about treatment applied in 51% of the room volume, and from my experience, nobody can imagine what unknown treatment of known size will do in some (unknown) room... So I still don't understand what you try to imply.
Old 19th December 2013
  #203
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Quote:
Originally Posted by boggy View Post
Here is 60dB spectrogram so you can try to find where is your 0.9s decay:

Attachment 376638

And RT60 too:

Attachment 376639

EDIT: You still know nothing about treatment applied in 51% of treatment, and from my experience, nobody can imagine what unknown treatment with known size will do in some (unknown) room... So I still don't understand what you try to imply.
In the sonogram with the 40 dB (from peaks) range, the floor was hit at around 550-600 ms, agreed? Unless the decay suddenly becomes non-linear (as it won´t if room well treated), the decay rate would end up where I´ve stated previously, agreed? And thus the decay time would end up at 0,9 seconds, do you not agree here? You don´t need to be rude (other do it so much better than you , I´m simply trying to understand what went wrong with that first sonogram …
Old 19th December 2013
  #204
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Quote:
Originally Posted by Jens Eklund View Post
In the sonogram with the 40 dB (from peaks) range, the floor was hit at around 550-600 ms, agreed?
Yes
Quote:
Originally Posted by Jens Eklund View Post
Unless the decay suddenly becomes non-linear (as it won´t if room well treated), the decay rate would end up where I´ve stated previously, agreed?
No, decay is not linear.
Quote:
Originally Posted by Jens Eklund View Post
And thus the decay time would end up at 0,9 seconds, do you not agree here?
No, I don't agree. As I already said, decay is not linear, especially NOT in the small rooms, and may depend on absorbing technique.
Quote:
Originally Posted by Jens Eklund View Post
You don´t need to be rude (other do it so much better than you , I´m simply trying to understand what went wrong with that first sonogram …
Ah... Sorry, I understand your intentions now, you actually tried to help me...

Nothing "went wrong" with my first sonogram, btw, it is perfectly ok, my customers like it very much...



Old 19th December 2013
  #205
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Quote:
Originally Posted by boggy View Post
Yes

No, decay is not linear.

No, I don't agree. As I already said, decay is not linear, especially NOT in the small rooms, and may depends on absorbing technique.

Ah... Sorry, I understand your intentions now, you actually tried to help me...

Nothing "went wrong" with my first sonogram, it is perfectly ok, my customers like it very much... btw



How do you feel the RT60 plot is holding up against the sonogram: ”RT60” of about 0,1 seconds at 200 Hz, or T60 according to the sonogram of about 0,7 seconds … there’s clearly a difference and it´s too big to blame on RT-measurements not being valid in this room size. Something is not right.

Do you have a non-linear decay (enough to consider that is) in the modal range in this room? It does not look like it when looking at the sonogram. Can you post a waterfall with a 60 dB range and a time range just long enough to cover the tail of the longest mode?

I´m only trying to understand why the first sonogram indicated a 0,9 second decay time.
Old 19th December 2013
  #206
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Quote:
Originally Posted by Jens Eklund View Post
How do you feel the RT60 plot is holding up against the sonogram: ”RT60” of about 0,1 seconds at 200 Hz, or T60 according to the sonogram of about 0,7 seconds … there’s clearly a difference and it´s too big to blame on RT-measurements not being valid in this room size. Something is not right.
Did you ever see REW spectrogram of the room with REW RT60 near or below 0.1s?
If you never tried... REW spectrogram never goes much below 600ms (with common settings), even if RT60 is equal or below 0.1s.
Quote:
Originally Posted by Jens Eklund View Post
Do you have a non-linear decay (enough to consider that is) in the modal range in this room? It does not look like it when looking at the sonogram. Can you post a waterfall with a 60 dB range and a time range just long enough to cover the tail of the longest mode?

I´m only trying to understand why the first sonogram indicated a 0,9 second decay time.
Spectrogram is not enough for you?
Old 19th December 2013
  #207
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Quote:
Originally Posted by boggy View Post
Did you ever see REW spectrogram of the room with REW RT60 near or below 0.1s?
If you never tried... REW spectrogram never goes much below 600ms (with common settings), even if RT60 is equal or below 0.1s.
Oh, I think we just found the problem

The sonogram in REW will correlate just fine with T60 values reported (and especially i you use the "Topt" option instead of RT60 which is not very useful anyway in such small rooms as recording and control rooms).

You should check your settings in REW or perhaps update to the lasted beta version and see if that helps.
Old 19th December 2013
  #208
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My room-rew-spectrogram.gif
Old 19th December 2013
  #209
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Quote:
Originally Posted by Jens Eklund View Post
Oh, I think we just found the problem

The sonogram in REW will correlate just fine with T60 values reported (and especially i you use the "Topt" option instead of RT60 which is not very useful anyway in such small rooms as recording and control rooms).

You should check your settings in REW or perhaps update to the lasted beta version and see if that helps.
-I use REW V5.01 Beta 17 build 2967
-Topt is just the same as T30, here.
Old 19th December 2013
  #210
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Quote:
Originally Posted by boggy View Post
-I use REW V5.01 Beta 17 build 2967
Weird, same here. Perhaps reinstall it and see what happens.
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