Modal - Stochastic Freqs. And Room Correction

rjharle

rjharle

Audioholic
Since room correction involves room calculations and a boat load of math. The findings are broken down into Modal, Stochastic and Hard Separation. Modal 20hz - 150hz, Stochastic 150hz - 20khz. Transition 100hz - 5khz. Modal are Room and can be corrected with EQ. Stochastic are direct and directional and cannot be corrected by EQ. Since the entire bandwidth can not be corrected by auto room correction and the cutoff is 150hz and Stochastic measured in is Absorption to achieve ITU RT60: ? Sabins.

Modal = auto room correction
What corrects Transition?
Stochastic = Acoustic treatments

Are room correction programs designed to cutoff above 150hz, since additional room correction could hurt rather than help?
Is there a way to avoid the room looking like an egg crate or checkerboard?
Does decoupling the room create more of a reflective surface? So far I've only checked soundproofing. (2x 5/8 sheetrock and green glue)
 
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ryanosaur

ryanosaur

Audioholic Overlord
There are some RCs that allow you to set a curtain or cut-off frequency (Dirac, Aud XT32, for example).
Common practice is to do so just above your room's Schroeder Frequency, usually somewhere between ~100-200Hz... (though I have seen different numbers ranging slightly higher rather than lower)... this being the point where your room stops acting as a resonator and the frequency will vary by room.
A cheaters way to see the Schroeder Frequency is to look at your in-room measurement, uncorrected, and judge where the peaks and dips begin to smooth out.

Of course, some people just say "set the curtain at 500 and call it a day."

Anyway... You don't want to cover everything in your room. IIRC, about 25% is all that is needed in most cases.

Treatments should be based on your room measurements and be placed strategically.

Why would decoupling the room create a more reflective surface?
 
rjharle

rjharle

Audioholic
There are some RCs that allow you to set a curtain or cut-off frequency (Dirac, Aud XT32, for example).
Common practice is to do so just above your room's Schroeder Frequency, usually somewhere between ~100-200Hz... (though I have seen different numbers ranging slightly higher rather than lower)... this being the point where your room stops acting as a resonator and the frequency will vary by room.
A cheaters way to see the Schroeder Frequency is to look at your in-room measurement, uncorrected, and judge where the peaks and dips begin to smooth out.

Of course, some people just say "set the curtain at 500 and call it a day."

Anyway... You don't want to cover everything in your room. IIRC, about 25% is all that is needed in most cases.

Treatments should be based on your room measurements and be placed strategically.

Why would decoupling the room create a more reflective surface?
So, I have an initial reading of 512 Sabins and you think 120 will smooth it out?
If I use a different RC, how would I integrate that into ARC, since I have an Anthem AVR?
I listen to my system at 75-80 db or Mommy aggro. So if I decouple the room, which sin't too difficult, there will be peace and I don't have to worry about dynamic range.
 
ryanosaur

ryanosaur

Audioholic Overlord
So, I have an initial reading of 512 Sabins and you think 120 will smooth it out?
If I use a different RC, how would I integrate that into ARC, since I have an Anthem AVR?
I listen to my system at 75-80 db or Mommy aggro. So if I decouple the room, which sin't too difficult, there will be peace and I don't have to worry about dynamic range.
I can't help you with Anthem Room Correction. If it does not allow you to set a curtain, then you have to deal with it, find a work around like the MiniDSP DDRC88A which if you can use will give you Dirac, or shop for a new AVR or Processor with the technology you want.

120 what? to smooth out your Sabins?

Decoupling a room is a very complex task. Doable, certainly... but not something I would recommend you do without much greater understanding...
Perhaps you are an architect or contractor?
Either way, your recent posts tell a different story about your understanding of acoustics. I applaud you learning about it.
 
rjharle

rjharle

Audioholic
I can't help you with Anthem Room Correction. If it does not allow you to set a curtain, then you have to deal with it, find a work around like the MiniDSP DDRC88A which if you can use will give you Dirac, or shop for a new AVR or Processor with the technology you want.

120 what? to smooth out your Sabins?

Decoupling a room is a very complex task. Doable, certainly... but not something I would recommend you do without much greater understanding...
Perhaps you are an architect or contractor?
Either way, your recent posts tell a different story about your understanding of acoustics. I applaud you learning about it.
I think ARC does allow a curtain/cutoff at 2khz Not sure that I can get down to 200hz I'll have to get back into it to check what the level is.

120 what? To smooth out your Sabins? - My room, as is, according to Absorption to achieve ITU RT60: 512 Sabins. You had said I would only need about 25% in most cases. Sabin = units of absorption.

Decoupling a room: Contractor
Gut the room down to the studs and fill voids with fiber wool. Install, on studs, RSIC-1 clips 2' on center horizontal Mount matching furring channel. Install 2 layers of 5/8" sheetrock, 1/4" spacing, sandwich with a layer of green glue. Seal any spaces or voids. I think that is it.

Understanding of acoustics:
My only hope is that someday I have your or TLS's understanding of the subject.:)
 
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