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should i consider EDT in addition to t30 on rew?
Old 4 weeks ago
  #1
should i consider EDT in addition to t30 on rew?

hi everyone i'm perfecting the acoustic treatment of my vocal booth. The values of the t30 are correct taking ebu tech into consideration, but I have noticed that in the edt there seems to be little high frequencies. Should I consider the edt for the acoustic treatment of my vocal booth which is approximately 4 meters X 3 meters in size?

the room has a fully absorbent ceiling with rock wool panels, a fully absorbent wall and all other reflective walls
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should i consider EDT in addition to t30 on rew?-edt-sala-regis.jpg   should i consider EDT in addition to t30 on rew?-whatsapp-image-2021-04-08-20.27.17.jpg  
Old 4 weeks ago
  #2
Here for the gear
All the parameteres in the RT60 graphs are estimation of the actual RT60 decay, i.e. T20 is based on the first 20 dB decay, T30 on 30 dB decay, Topt uses a slightly complex algorithm to get RT60...

EDT stands for Early Decay Time, which is RT60 computed from the decay of the first 10 dB, which in my experience, in some situations the "behaviour" of the room is not well seen enough to make assumption for RT60.

So you must take EDT with a grain of salt, and think first about the room and its use, for a vocal booth I wouldn't care about EDT, anyways I am no expert so it is well open for discussion .
Old 4 weeks ago | Show parent
  #3
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🎧 5 years
Quote:
Originally Posted by K.I. ➡️
All the parameteres in the RT60 graphs are estimation of the actual RT60 decay, i.e. T20 is based on the first 20 dB decay, T30 on 30 dB decay, Topt uses a slightly complex algorithm to get RT60...

EDT stands for Early Decay Time, which is RT60 computed from the decay of the first 10 dB, which in my experience, in some situations the "behaviour" of the room is not well seen enough to make assumption for RT60.

So you must take EDT with a grain of salt, and think first about the room and its use, for a vocal booth I wouldn't care about EDT, anyways I am no expert so it is well open for discussion .
The edt is not compute from thre rt60.
The topt is not a rt60 measurement (see help rew)
The rt60 in the academic world do not change with the mic location. This is a room property.
The edt changes with the mic location. This is a listening location property.

The EDT is fully usable.
Old 4 weeks ago | Show parent
  #4
Quote:
Originally Posted by dinococcus ➡️
The edt is not compute from thre rt60.
The topt is not a rt60 measurement (see help rew)
The rt60 in the academic world do not change with the mic location. This is a room property.
The edt changes with the mic location. This is a listening location property.

The EDT is fully usable.
so should i rely on the t30 or the edt to treat a voice tracking room? the t30 in my room respects the limits imposed by ebu tech, but the edt is completely different

so if I try to increase the reflective surfaces to increase the high frequency edt (my room is poor in high frequencies if I have to consider the edt, instead it is rich in high frequencies if I take into account the t30), the t30 exceed the limits imposed by ebutech (I know that you must not exceed 50 ms downwards or upwards)

furthermore, if the t30 must respect the ebu tech limits, which values must the edt respect to be suitable for good acoustics?
Old 4 weeks ago
  #5
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🎧 5 years
1D diffusor - vertical or horizontal?

The ebu advice are based on the rt60.
The edt is a different thing.
A rt60 is a room property and does not change with the mic location.
Your T30 show no decay in the high frequency, It is very astonishing.

The edt is the listening position property.
Your edt show a lost of energy in the mid at the mic position if your measurements are valid regarding the T30.


Use your ears.
Old 4 weeks ago | Show parent
  #6
Quote:
Originally Posted by dinococcus ➡️
1D diffusor - vertical or horizontal?

The ebu advice are based on the rt60.
The edt is a different thing.
A rt60 is a room property and does not change with the mic location.
Your T30 show no decay in the high frequency, It is very astonishing.

The edt is the listening position property.
Your edt show a lost of energy in the mid at the mic position if your measurements are valid regarding the T30.


Use your ears.
what? my t30 is about 200ms from 2000hz up, it's actually the edt which doesn't show high frequency information

the slat walls are horizontal, you can see them in the photo I had posted
Old 4 weeks ago | Show parent
  #7
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akebrake's Avatar
 
🎧 5 years
Quote:
Originally Posted by grignacarbo ➡️
so should i rely on the t30 or the edt to treat a voice tracking room? the t30 in my room respects the limits imposed by ebu tech, but the edt is completely different ...
Couple of questions...

Which EBU document are you referring to?

Pls describe the rest of your room.

How is it measured?

What speaker and measurement mic?

Position of speaker and mic.

Pls upload the mdat.

Best
Old 4 weeks ago | Show parent
  #8
Lives for gear
 
🎧 5 years
Quote:
Originally Posted by grignacarbo ➡️
what? my t30 is about 200ms from 2000hz up, it's actually the edt which doesn't show high frequency information

the slat walls are horizontal, you can see them in the photo I had posted
The picture in your first post is without legend.
Slat wall, What is it doing here?
The edt shows your measures are problematic.
Old 4 weeks ago | Show parent
  #9
Quote:
Originally Posted by dinococcus ➡️
The picture in your first post is without legend.
Slat wall, What is it doing here?
The edt shows your measures are problematic.
why does the edt show problems? i added the slat on the wall in order to increase the high frequencies, this worked on the t30, but in the edt not much has changed. But are you sure that EDT is an important parameter? I am coming to the conclusion that the EDT should not be taken into consideration because if I were to continue increasing the reflective walls to increase the high frequencies in the EDT, I would increase the reflections in the room and therefore make the sound less controlled and worse, consider that if the edt shows a drop in the high frequencies, my room does not sound dead in the high frequencies, it sounds quite balanced, but I can sense that the vocal recordings are distorted by reflections
Old 4 weeks ago | Show parent
  #10
Quote:
Originally Posted by akebrake ➡️
Couple of questions...

Which EBU document are you referring to?

Pls describe the rest of your room.

How is it measured?

What speaker and measurement mic?

Position of speaker and mic.

Pls upload the mdat.

Best
I rely on the hofa calculator which should base you on the tolerances of ebu tech but I don't know exactly which one, here is the link https://hofa-akustik.de/en/room-acoustics-calculator/

the measurements are made with a tannoy 802 monitor and a behringer microphone spaced about 50 cm apart, in practice the tannoy monitor is placed in the center of the room, in the direction of the slat wall you see in the picture, and emits the sound towards the parallel front wall , which is a simple plasterboard wall (so the slats are behind the monitor), but I also made the measurements in reverse, so the result is similar
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