R/E/P Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [All]   Go Down

Author Topic: Optimal Mastering Room Dimensions?  (Read 6879 times)

sui-city

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 330
Optimal Mastering Room Dimensions?
« on: April 24, 2004, 10:03:45 am »

Hey all!

Just wondering if you guys could give me some insight into good room dimensions for a matering sutiod.

Assume you can have a room of any shape or size, what would it be?

Thanks for the help.

Logged

bblackwood

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7036
Re: Optimal Mastering Room Dimensions?
« Reply #1 on: April 24, 2004, 06:15:15 pm »

Well, there's no perfect room, but if you pick up something like F. Alton Everest's 'Master Handbook of Acoustics' you can see charts of 'good sounding' ratios as well as ways to determine which dimensions yield the best low freq room response.
Logged
Brad Blackwood
euphonic masters

sui-city

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 330
Re: Optimal Mastering Room Dimensions?
« Reply #2 on: April 24, 2004, 06:29:42 pm »

Brad,

Thank you. I will definitely check it out.
Logged

chrisj

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 959
Re: Optimal Mastering Room Dimensions?
« Reply #3 on: April 25, 2004, 03:00:57 am »

Some ratios that are said to be good (F. Alton Everest- 'have stood the test of time') in rough order of worse-to-better:
1 - 1.14 - 1.39
1 - 1.28 - 1.54
1 - 1.60 - 2.33

I'm currently in very much 'none of the above, not even close', but hope to be setting up shop soon in a room very close to the second example. It's actually quite interesting- I can go into an apparently similar room and clap and the reverb has a very distinct color- go into the 'optimal' room and clap and the verb sort of vanishes into colorlessness. Instead of 'Klonng' it's like 'Khhhh' Smile no mode reinforcements!

bblackwood

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7036
Re: Optimal Mastering Room Dimensions?
« Reply #4 on: April 25, 2004, 07:09:13 am »

chrisj wrote on Sun, 25 April 2004 02:00

It's actually quite interesting- I can go into an apparently similar room and clap and the reverb has a very distinct color- go into the 'optimal' room and clap and the verb sort of vanishes into colorlessness. Instead of 'Klonng' it's like 'Khhhh' Smile no mode reinforcements!

Just remember that clapping will not excite the low freq modes determined by room dimensions - claps are high enough in freq to be controlled by surface treatments alone...
Logged
Brad Blackwood
euphonic masters

Viitalahde

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1069
Re: Optimal Mastering Room Dimensions?
« Reply #5 on: April 25, 2004, 08:02:57 am »

Treatment can do wonderful job in the not-so optimal rooms also. I bought a bunch of rigid rock wool and did everything I could to tame the low frequencies and ugly flutter echoes in my 2,2m (width) * 4,5m (length) * 2,55m (height) room. Monitoring on the 2,2m wall, Dynaudio BM6A's flat against it.

I treated corners, side walls and some of the roof and it all came out absolutely wonderfully - just needed some experimenting. The room is tiny but with the treatment and two days work of monitor placement, I have a good bass response to the deepest, good and precise imaging and narrow mono image. The sweet spot is also pretty big.

The acoustically wiser people are probably somewhat right with the optimal room dimensions. But when the dimensions are not good, acoustic treatment can work wonders.


Jaakko
Logged
Jaakko Viitalähde
Virtalähde Mastering, Kuhmoinen/Finland
http://www.virtalahde.com
   http://www.facebook.com/pages/Helsinki-Finland/Virtalahde-Ma stering/278311633180

chrisj

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 959
Re: Optimal Mastering Room Dimensions?
« Reply #6 on: April 25, 2004, 03:18:08 pm »

bblackwood wrote on Sun, 25 April 2004 07:09


Just remember that clapping will not excite the low freq modes determined by room dimensions - claps are high enough in freq to be controlled by surface treatments alone...



Mm- you're right, it wasn't telling me that, was it? Again it's a good thing the room dimensions are close to a considered-optimal ratio. When I ran my room mode calculations (Everest again for the basic math) I ran 'em up to at least 1K and they still stayed pretty even- maybe that's what I'm hearing.
Surface treatments are fun. I wrote a program to generate quadratic residue diffusor construction plans and I'm going to make some out of shipping plank styrofoam. You can get it scored to break into 4x4x1" pieces. I'm thinking big back-wall panels covering more area, but less efficient than, a Skyline. Might sort of even out to be about right.
I'm heroically resisting the temptation to try and do the ceiling in 1 inch deep 4x4x1" diffusion pattern... I don't think anybody ever needs to attack flutter echo that hard. I am curious, however, about how well the shipping plank glue would hold to ceiling paint Wink it may be a moot point, however, as I doubt I could meet fire codes with styrofoam on the ceiling. Maybe there's some other material that would be usable, or maybe it's best forgotten.
...which suggests that maybe I'd best churn out deeper diffusors that cover less wall area, just to stay on the safe side of fire codes...

Ronny

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2739
Re: Optimal Mastering Room Dimensions?
« Reply #7 on: April 25, 2004, 04:36:16 pm »



There are thousands of houses in my area built with styrofoam insulation, no problems with fire codes. BUT, certainly you can find better DIY material than styrofoam plank's. They are too reflective, IMHO.
Logged
------Ronny Morris - Digitak Mastering------
---------http://digitakmastering.com---------
----------Powered By Experience-------------
-------------Driven To Perfection---------------

barefoot

  • Full Member
  • ***
  • Offline Offline
  • Posts: 196
Re: Optimal Mastering Room Dimensions?
« Reply #8 on: April 25, 2004, 08:53:11 pm »

sui-city wrote on Sat, 24 April 2004 07:03

Assume you can have a room of any shape or size, what would it be?

First off is non-parallel walls, floor and ceiling.   This helps break up standing waves, spreading them more weakly across the frequency spectrum.   Secondly, you want diffuse wall reflections that arrive at the listing position no earlier than about 22 milliseconds after the direct sound from the speakers.  

There is quite a lot more to this whole subject.   You also might like to join us over at the Recording Studio Design Forum.Smile

Thomas

Logged
Thomas Barefoot
 Barefoot Recording Monitors

Ed Littman

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 877
Re: Optimal Mastering Room Dimensions?
« Reply #9 on: May 03, 2004, 11:46:44 am »

bblackwood wrote on Sat, 24 April 2004 18:15

Well, there's no perfect room, but if you pick up something like F. Alton Everest's 'Master Handbook of Acoustics' you can see charts of 'good sounding' ratios as well as ways to determine which dimensions yield the best low freq room response.


Great! I just ordered the book. It looks like this year I'll be able to build a good room from scratch. of course I'll get an accustition in, but this will give me the heads up. The problem for me like allways is understanding the Math.
Thanks,
Ed
Logged

Ethan Winer

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 571
Re: Optimal Mastering Room Dimensions?
« Reply #10 on: May 03, 2004, 02:58:52 pm »

Sui and Chris,

See the Acoustics FAQ, second in the list on my Articles page:

www.ethanwiner.com/articles.html

In particular, read the section about room modes, and also the sidebar that describes the mode calculator you can download for free.

> I ran 'em up to at least 1K and they still stayed pretty even <

All rooms are okay up that high, and have close mode spacing there. The real problems are all below 300 Hz.

> do the ceiling in 1 inch deep 4x4x1" diffusion pattern <

Unfortunately, that won't do anything for room modes.

--Ethan

Toby M

  • Full Member
  • ***
  • Offline Offline
  • Posts: 112
Re: Optimal Mastering Room Dimensions?
« Reply #11 on: May 04, 2004, 04:40:20 am »

Just a thought, have mastering rooms gone through a similar transition between Lede & dele to nonenvironment that we have seen in conventional studios?

Just out of curiosity what Rt60 is normally used in Mastering rooms. I know you guys don't judge reverb content as much as we do but when you compress stuff the reverb in the material gets louder. That can't be easy to judge if you're in a quite reverbant room?

Yours  / Toby
Logged
www.cascatoma.com
Smiles can be heard !

blairl

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 376
Re: Optimal Mastering Room Dimensions?
« Reply #12 on: May 22, 2004, 03:25:18 pm »

chrisj wrote on Sun, 25 April 2004 13:18


I wrote a program to generate quadratic residue diffusor construction plans and I'm going to make some out of shipping plank styrofoam.


Do you have a program to calculate the well depths of a 2 dimensional quadratic residue diffusor?
Logged

jfrigo

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1029
Re: Optimal Mastering Room Dimensions?
« Reply #13 on: May 22, 2004, 05:04:48 pm »

blairl wrote on Sat, 22 May 2004 12:25


Do you have a program to calculate the well depths of a 2 dimensional quadratic residue diffusor?


That's easy to calculate by looking at the chart in Everest's book, but I guess a spreadsheet would make life easier. Maybe I'll make one in Excel if I have nothing to do one of these days. A small one based on the prime number 11 would have depth proportions of 01422410. The specific depth and width of the wells depends on what band you want it to be effective at. You can take several of these small ones and in turn make those the wells for a large one of the same proportionality and you'll have essentially a multiband diffusor called a diffractal that will diffuse over a larger portion of the spectrum.

As for dimensions, everybody has already mentioned the modal calculator and optimum ratios suggested by researchers. There's a visual aid in several acoustics books, Everest included I believe, that looks like a little amoeba on an X,Y grid where you can see if your planned room ratio fits into the range of desirable ratios. You can also search for Bolt, Sepmeyer, and Louden and see what they have to say. If you find a Sepmeyer or Louden ratio that also falls into bolt's "amoeba", you're probably off to a good start.

As for splaying walls, there are many reasons that room geometries more complex than rectangular are a good idea,including control of reflections to make a RFZ at the listening position. While it does alter how the room modes behave, it's not a cure for them. Some will say it doesn't eliminate them, just makes them harder to predict. While this has merit, I still wouldn't design a perfectly rectangular room including a flat ceiling. Splayed walls can help to diffuse the modes a bit, help control the early reflections at your listening position, and eliminate flutter echo.

If you splay walls (and ceilings - that's a subject for later), keep the room symetrical and when figuring out the ratio, you can estimate by calculating for a room of the same volume. In other words, if the room is 10 feet wide at the front wall and 12 feet wide at the rear, calculate for 11 feet as the width and you'll be in the ballpark. In the end, if you want to really get a handle on it, you'll have to take measurements in the room once it's finished and treat it accordingly.

Logged

bblackwood

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7036
Re: Optimal Mastering Room Dimensions?
« Reply #14 on: May 22, 2004, 05:53:35 pm »

I have recently contracted George Augspurger to design my new facility. When initially speaking with George, I told him he had a blank slate and asked him what dimensions to use for the shell of the room.  He told me to plan on the room being 20'x30'x12'.

More details as the room/build developes...
Logged
Brad Blackwood
euphonic masters

Ed Littman

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 877
Re: Optimal Mastering Room Dimensions?
« Reply #15 on: May 22, 2004, 08:02:37 pm »

That's about the size room I asked Francis Manzella about at FM Design. I'll call in next week for more details.
He pointed out The possible costs involved in a high quality surround capable mastering suite can run from $125/SF up to $400/SF. On the small scale you are talking (approx 500 SF room plus support spaces, totaling less than 1000 SF).

And furthure added  Fees for a single room mid-high level mastering suite design would run in the area of $15,000 - $18,000 for interiors fit out only. This would include everything from floor, wall and ceiling construction through acoustic finishes, electrical installation and mechanical specification along with all detailing. It does not include design or consulting required for any structure which would be additional.

Brad, is this inline in comparison to your devloping situation?
Ed
Logged

bblackwood

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7036
Re: Optimal Mastering Room Dimensions?
« Reply #16 on: May 22, 2004, 08:06:39 pm »

GA told me to budget $150/foot to build plus his design and consultation (which is amazingly reasonable). Since I am building the facility on some wooded land, I can count on a bit less build-out costs as isolation won't be as hard to accomplish as it is in the city environment...
Logged
Brad Blackwood
euphonic masters

Ed Littman

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 877
Re: Optimal Mastering Room Dimensions?
« Reply #17 on: June 23, 2004, 01:00:17 am »

bblackwood wrote on Sat, 22 May 2004 20:06

GA told me to budget $150/foot to build plus his design and consultation (which is amazingly reasonable). Since I am building the facility on some wooded land, I can count on a bit less build-out costs as isolation won't be as hard to accomplish as it is in the city environment...


Hi Brad,
I'm interested in contacting George Augspurger.His personal info is hard to come by, so PM me if you think thats better.
In the next few months I'm about to close on a great property in Northern N.J., 3/4 of an acre & of course I'm taking over the garage. It happens to be poured cement & 24x20 from the outside, 10 ft ceiling with an attic. when I break through the attic it will dome to about 15ft.
I speak to a few well known designers before making a decision.
Thanks,
Ed
Logged

bblackwood

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7036
Re: Optimal Mastering Room Dimensions?
« Reply #18 on: June 23, 2004, 03:36:27 pm »

George Augspurger
Perception Inc
537 Cerro Gordo St
Los Angeles, CA 90026
(323) 660-9351

Easy like pie.
Logged
Brad Blackwood
euphonic masters

Ed Littman

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 877
Re: Optimal Mastering Room Dimensions?
« Reply #19 on: June 23, 2004, 04:24:23 pm »

Thank You
e
Logged

j.hall

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 3787
Re: Optimal Mastering Room Dimensions?
« Reply #20 on: June 24, 2004, 04:39:41 pm »

bblackwood wrote on Sun, 25 April 2004 06:09


Just remember that clapping will not excite the low freq modes determined by room dimensions - claps are high enough in freq to be controlled by surface treatments alone...




we use a .44 caliber revolver (firing blanks of course) and an Ivie PC-40 to calc RT60 in 1/3 octave bands

hand clapping is a good way to hear if you have any high frequency flutter echo.....



Logged
Pages: 1 2 [All]   Go Up