The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
reduce reverberation time on high frequencies
Old 6 days ago
  #1
Gear Head
 

reduce reverberation time on high frequencies

hi I have attached the photo of my room which has two walls filled with rock wool covered by the trevira fabric which is similar to the camira cara. I believe that this fabric slightly reflects the high frequencies, since I created these fake rock wool walls, the reverberation time is no longer balanced. how can i decrease reverberation frequency decay from 1000hz to up? obviously the frequency decay time below 1000 hz must not be decreased
Attached Thumbnails
reduce reverberation time on high frequencies-studio2.jpg  
Old 6 days ago
  #2
Lives for gear
 
Jason Foi's Avatar
 

Que?! Your room is dead as can be. In your other thread you wanted to liven it up! Stick to one thread, its easier for you to get help and doesnt waste everybodys time
Old 6 days ago
  #3
Gear Head
 

Quote:
Originally Posted by Jason Foi View Post
Que?! Your room is dead as can be. In your other thread you wanted to liven it up! Stick to one thread, its easier for you to get help and doesnt waste everybodys time
my room has a greater decathing time on high frequencies but is lacking on medium frequencies that have a decay time of 0.1 ms, so I want that even high frequencies have a similar decay time, currently the high frequencies have a time decay of 0.2 ms
Old 6 days ago
  #4
Lives for gear
The issue is the 0.1 ms not the 0.2ms
Old 6 days ago
  #5
Lives for gear
 
Jason Foi's Avatar
 

Quote:
Originally Posted by grignacarbo View Post
my room has a greater decathing time on high frequencies but is lacking on medium frequencies that have a decay time of 0.1 ms, so I want that even high frequencies have a similar decay time, currently the high frequencies have a time decay of 0.2 ms
The advice you recieved from everyone on your other thread is correct. Pick one of the many ways you were told to return mid-high frequency energy and do it. Or dont, its up to you, but the ball is in your court. Theres nothing new to discuss.
Old 6 days ago
  #6
Gear Head
 

0.1 might be fine to record the voice as long as the decay time is linear over the whole range of frequencies, so how can I make it balanced?

there are two ways to go:

- increase the decay time of the medium frequencies to get everything to 0.2 ms

- or alternatively decrease the decay time of high frequencies to get everything to 0.1 ms
Old 6 days ago
  #7
Gear Head
 

Quote:
Originally Posted by Jason Foi View Post
Que?! Your room is dead as can be. In your other thread you wanted to liven it up! Stick to one thread, its easier for you to get help and doesnt waste everybodys time
the problem is that I didn't understand how to increase the medium frequencies
Old 6 days ago
  #8
Lives for gear
 
Jason Foi's Avatar
 

Slats, pegboard, thick plastic, perforated metal, diffusers, etc, anything thats not soft and fluffy. Cover all the inslation you can that is NOT a first reflection point. You can use this to your advantage and increase LF absorbtion if needed or simply return mid-high frequency energy.
Old 6 days ago
  #9
Gear Head
 

Quote:
Originally Posted by Jason Foi View Post
Slats, pegboard, thick plastic, perforated metal, diffusers, etc, anything thats not soft and fluffy. Cover all the inslation you can that is NOT a first reflection point. You can use this to your advantage and increase LF absorbtion if needed or simply return mid-high frequency energy.
moreover if the fabric is creating this imbalance of the decay time it will absorb the medium frequencies more than the high frequencies. I found the technical data of the trevira fabric here Tessuto fonotrasparente in poliestere 100% certificato - Oudimmo


I don't want to increase the high frequencies because they have a decay time of 0.2 ms which is high for a small room like mine. I need to increase the decay time of the mid frequencies selectively.
Old 6 days ago
  #10
Gear Addict
 

Does anybody have a link to the "other thread"? I can't see any point in replying here, if the same question is already under discussion elsewhere...
Old 6 days ago
  #11
Gear Head
 

Quote:
Originally Posted by Soundman2020 View Post
Does anybody have a link to the "other thread"? I can't see any point in replying here, if the same question is already under discussion elsewhere...
honestly, I have not received any reply for solved my problem in a right way. If your advice is to add slat wood, increase the time of the mid and high frequencies, so it may happen that the middle frequencies rise to 0.15 ms and the high frequencies exceed 0.2 ms.

Is it not possible to selectively increase the decay time of the missing frequencies (I refer to the medium frequencies)?
Old 6 days ago
  #12
Lives for gear
 
Jason Foi's Avatar
 

Your fabric is not the problem, the chart shows an increase at HF absorbtion. It seems the insulation on your walls is too dense and reflects HF and absorbs mostly mids if i had to guess. Link me to the product on your walls please
Old 6 days ago
  #13
Lives for gear
 
Jason Foi's Avatar
 

Quote:
Originally Posted by Soundman2020 View Post
Does anybody have a link to the "other thread"? I can't see any point in replying here, if the same question is already under discussion elsewhere...
acoustic treatment without treating the ceiling
Old 6 days ago
  #14
Gear Head
 

Quote:
Originally Posted by Jason Foi View Post
Your fabric is not the problem, the chart shows an increase at HF absorbtion. It seems the insulation on your walls is too dense and reflects HF and absorbs mostly mids if i had to guess. Link me to the product on your walls please
from the graph it seems that the fabric is ok. but I don't understand why since the creation of rock wool walls the time of decadence of high is unbalanced compared to medium. I use two types of rock wool inside the walls, a density of 20 kg and a density of 50 kg on the surface, so I don't think this could be the problem, many in this forum use the 50 kg density
Old 6 days ago
  #15
Lives for gear
Man, you got all help needed. But, you obviously didn't read any other thread linked in your thread.
Old 5 days ago
  #16
Gear Head
 

Quote:
Originally Posted by JayPee View Post
Man, you got all help needed. But, you obviously didn't read any other thread linked in your thread.
I read every single piece of advice but I'm just confused. What do you suggest? should I add wooden slats? if so, what is the width and distance?
Old 5 days ago
  #17
Lives for gear
Quote:
Originally Posted by grignacarbo View Post
from the graph it seems that the fabric is ok. but I don't understand why since the creation of rock wool walls the time of decadence of high is unbalanced compared to medium. I use two types of rock wool inside the walls, a density of 20 kg and a density of 50 kg on the surface, so I don't think this could be the problem, many in this forum use the 50 kg density
You are on the wrong path. All what you do, is to measure the sound parameters produced by a speaker in one position in a room.

I think when you record a voice, the head is not at the place of your speaker: against a wall on a desk.

So even it is not the right way, take a measurement where the singer is, by setting the speaker at the height of the head and set the mic at the place of the mic used for the recording.
Old 5 days ago
  #18
Gear Head
 

Quote:
Originally Posted by dinococcus View Post
You are on the wrong path. All what you do, is to measure the sound parameters produced by a speaker in one position in a room.

I think when you record a voice, the head is not at the place of your speaker: against a wall on a desk.

So even it is not the right way, take a measurement where the singer is, by setting the speaker at the height of the head and set the mic at the place of the mic used for the recording.
I put the microphone even where I sing, the problem is the same
Old 5 days ago
  #19
Lives for gear
Quote:
Originally Posted by grignacarbo View Post
I put the microphone even where I sing, the problem is the same
And the speaker?
Old 5 days ago
  #20
Gear Addict
 

Quote:
If your advice is to add slat wood,
That would probably be very good advice, yes. Perforated panel would be another option. Tune them right, and you can get them to have whatever spectrum you need.

Quote:
so it may happen that the middle frequencies rise to 0.15 ms and the high frequencies exceed 0.2 ms.
You'll never know if you don't try...

Quote:
Is it not possible to selectively increase the decay time of the missing frequencies
Yes, it is. but the lower the "Missing" frequency is, the harder it is to restore. Many rooms that are treated with just "standard" materials spread around all over, end up with a dip around 250 Hz, which is hard to get back again.

But where is your REW data? Why don't you want a decay time over 200ms in the high end? What's wrong with that? What is your overall target for the room? How large are the variations between adjacent bands? How does the overall decay curve compare with the suggest curves in common specs?

- Stuart -
Old 5 days ago
  #21
Gear Addict
 

Quote:
Originally Posted by Jason Foi View Post
Oh THAT one! OK, I get it. The OP didn't like the advice he was given there, from multiple experts, so he started a new thread, hoping for different advice that he DOES like...

Ummm....

I'm not gonna play that game...
Old 5 days ago
  #22
Gear Head
 

Quote:
Originally Posted by Soundman2020 View Post
That would probably be very good advice, yes. Perforated panel would be another option. Tune them right, and you can get them to have whatever spectrum you need.

You'll never know if you don't try...

Yes, it is. but the lower the "Missing" frequency is, the harder it is to restore. Many rooms that are treated with just "standard" materials spread around all over, end up with a dip around 250 Hz, which is hard to get back again.

But where is your REW data? Why don't you want a decay time over 200ms in the high end? What's wrong with that? What is your overall target for the room? How large are the variations between adjacent bands? How does the overall decay curve compare with the suggest curves in common specs?

- Stuart -
the rew data is in the other discussion. I did not say that I do not want to bring the decathing time to 0.2 ms, I am interested that the decay time is balanced from the mid to the high frequencies,

to get good acoustics the decadence time must be balanced, right? if yes, it's ok for me to take everything to 0.2 ms.
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Similar Threads
Thread
Thread Starter / Forum
Replies
KenjiMax / Studio building / acoustics
2
ErroneousDylan / Studio building / acoustics
8
Audioactive / Studio building / acoustics
15
steffen / Studio building / acoustics
4

Forum Jump
Forum Jump