Interpretation of the RT60

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lerryns
Posts: 37
Joined: Fri Sep 08, 2006 11:57 pm
Location: Caracas, Venezuela
Contact:

Interpretation of the RT60

Post by lerryns »

Hi my name is Lerryns Hernández and I live in Caracas, Venezuela. I am designing my recording studio. You can see the process in
http://www.johnlsayers.com/phpBB2/viewtopic.php?t=7020

I calculate the RT60 using the Reverb Calculator in the Recording Manual and I have these figures:

RT60 Studio

125 250 500 1000 2000 4000
0,14 0,21 0,26 0,21 0,17 0,16


RT60 Control Room

125 250 500 1000 2000 4000
0,19 0,21 0,25 0,19 0,16 0,16

What should I do with that informations? What actions I need to take based on those figures? Is the studio and Control Room balanced?

Thanks in advanced for all your comments...

Lerryns Hernández
www.lerryns.com




lerryns
Posts: 37
Joined: Fri Sep 08, 2006 11:57 pm
Location: Caracas, Venezuela
Contact:

Post by lerryns »

Greetings to all in this forum :D Many visits but nobody respond...

Commentaries, advice and ideas are important for my.

Thanks in advanced for all your comments...

Lerryns Hernández
www.lerryns.com
z60611
Posts: 251
Joined: Fri Jun 18, 2004 9:08 am
Location: Ontario, Canada

Post by z60611 »

You could type in your room dimensions into here
http://www.bobgolds.com/Mode/RoomModes.htm
and on the middle right hand side you'll see a line
RT60 (ITU/EBU Control Room Recommended): xxx ms
That's your target for the control room.
(not for other rooms, like the studio).
A little longer in the 125hz and down, and a little shorter in the 4khz and up, is just fine.

You have the room built, so you could ignore the calculations of what your RT60 might be, and do some measurements with software like RplusD. There is some debate over whether the software reports a real RT60, or whether the waterfall charts show a real decay of 60dB, but my bet is it's still better than calculations/estimations, and you might also discover an unpredicted anomaly or two or three.

For a list of tests, and the order to do them in, please see
http://www.sencore.com/newsletter/Nov03 ... lpart2.htm

The calculations are only as good as what you included. Did you include everything (chair, carpet, walls, windows, doors, drapes, you, air, etc)? Did you make adjustments to the absorption coefficients due to the differences in the way they were lab measured, vs how they are being used in your room? Did you adjust overall based on the assumptions that are fundimental to the RT60 equasion that's being used? If your calculated values after that are off from the recommended RT60 above, then consider corresponding treatment to deal with that.
Once you have the correct total absorption in the room, then you can fiddle with placement to deal with other acoustical issues -- although in the real world people tend to do things in all kinds of orders.
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