Mix room with a pitched ceiling

[PhilE]

From you guys out there in the know about acoustics- I am in the planning stages of my new room- the site I have been offered has a pitched roof, its a single story building and the peak would run across the middle of my control room- ie the roof would slope up from the wall in front of the console and down again behind my head.
How should I treat this? Square it off and have a low ceiling?
The room will be about 21' x 15' after the wall treatment has gone in.

[The Byre]

Symmetry is important. Make sure that the room is a symmetrical as you can make it and put in a 'cloud', i.e. a absorbent ceiling that swallows all reflections.

Also avoid reflective surfaces on the sides. I know that some designers put glass doors and other reflective surfaces on the sides on some of their control rooms - and trust me here, they are wrong. The result is severe dips and peaks between 200 and 400Hz because the opposite side monitor reflects back into the room and causes phase problems at the monitoring position.

But there is nothing inherently wrong with a sloping ceiling - in fact you can use this to your advantage.

[The MPCist]

The space in which I built my studio had a pitched ceiling.. kinda like a church if you know what i mean. We kept part of the ceiling pitched but used the space that was covered into a super bass trap and broadband treatment.

It sounds great and feels really nice. Very accurate monitoring as expected after building with S3As and PMC TB2/brystons used for testing. We're waiting for the MM27's to arrive and so I can get rid of the S3A's....

Yeah, keep the sloped ceiling but make sure you get an acoustician to work out the details.

[PhilE]

Thanks guys, the walls are going to be fabric covering rockwool type materials- will be pretty dead but with diffusers built in at key points.
There will be no window to the performance space as this is primeraly a mix room.
However- at the back of the room directly behind the listening position I want to put in a strip of glass bicks- you know the really 70s ones(!) - to allow natural daylight in but obscure the view from the outside world... the glass bricks would not go to the outside btw- just to a space with a window in it.

I had a room with a pitched roof before and it was really reflective in a bad way- would ping back at the listening position and things got very muddy and confused til I srung foam up to create a flat section above and behind me... is that what you mean by a cloud? I was never very happy with that old room - left after 6 months.

[The Byre]

Glass bricks are very reflective! Try turning this through 180 and having the daulight in front of you, then you can build a classical LEDE (live ned, dead end) 70's style room.

[PhilE]

Yeah, I know.... I dont really have that option because of where the door is... and moving that would ripple down the complex and put me behind schedule!
As it is the door is 2/3 the way down one side of the room if I 180 the design it is next to the consoles optimum position and will be an asymetry at a key spot.
I would expect to need difusers at the back of the room where these bricks would be- my question is are they too much?
I would dearly love to not have to spin the room for other reasons too- future options would put a booth/window system in an odd place if I spin the room, not to mention the initial impact would be much less for clients entering the room almost behind the console.

For me every room is a toss up between vibe and acoustics- you can never ignore either one and they rarely work together! I was realy hoping that my glass bricks would bring a reaction of 'wow- yeah... great difusers!' OK, OK, this was very much wishful thinking, but the mock ups look SO cool!

[Ethan Winer]

Originally Posted by PhilE

the roof would slope up from the wall in front of the console and down again behind my head. How should I treat this? Square it off and have a low ceiling?

A peaked ceiling is fine, but it should be behind your head and you need to treat under the peak to avoid focusing. The photo below shows how I treated under the peak in my home studio.

--Ethan

[PhilE]

Thanks,

That looks like a similar kind of pitch too.

Anyone want to suggest another way around my glass issue?

P.

[nathanvacha]

re: the glass brick issue... how tall are the walls? is it an option to still include them, but have them a little bit higher than ear hight? Not quite in the wall/ceiling joint, but a bit higher up? I would think you can still pull that off acoustically while achieving your daylight effect.

[PhilE]

Originally Posted by nathanvacha

re: the glass brick issue... how tall are the walls? is it an option to still include them, but have them a little bit higher than ear hight? Not quite in the wall/ceiling joint, but a bit higher up? I would think you can still pull that off acoustically while achieving your daylight effect.

Yeah, I would think so, although it would be a tougher build... the acoustic purpose false walls would have to support glass bricks rather than nothing.

Is there something else that will let daylight through rather than the glass bricks- with better acoustic performance? Remembering that I want the distorted visual effect of the glass brick. Is there a plastic version that might have a less detrimental effect on the acoustics, or a way of laying them so they are so staggered that they diffuse?

[Dan]

I always thought these were cool.

http://www.rpginc.com/products/clearsorber/index.htm

[PhilE]

Interesting- thanks!

[channelcat]

You might want to check out Lightblocks (http://www.lightblocks.com). I've seen samples of these, and they're pretty cool. I'm still trying to figure out something to build with them. Again, you don't want to put these at listening level, but they might work a little higher up on the rear wall.

Stu

[PhilE]

Hmmm.. not too sure how the lightblocks can help my situation- they look cool but to be honest I didnt get the impression from the gallery that they would give the natural light I want- I could just put some daylight bulbs up and diffuse them for that same effect I feel.

Cheers for the info though- for some folks that would be just what they're after.

[Ruphus]

Anyone experienced those "clearsorbers"? ... And what´s their price?

Thanks,

Ruphus

[PhilE]

I learned to day that they are REALLY expensive and the acoustic treatment guys (RPG stockists) in the UK won't get involved!
They say they have a huge lead time, a huge price tag and suggest getting a drill and some perspex!
They wouldnt be drawn on whether it would work as they say they've never demo'd them

SO- back to the Glass Block issue again!
I'm starting to think 'sky lights' instead??

[Ruphus]

Thanks for the info!

I expected them to be very expensive and figured that one could get himself plexiglas and drill the holes himself.
Only that it would take ages to drill 40000 holes per square meter. :O( - And you would even need to drill slowly if you didn´t want to exchange the drills tip every other minute for it becoming blund from too much heat.

It should be much easier if a manufacturer of plexiglas would just mould them this way.

But if those holes worked well I would be very interested into making use of the concept, as I´m currently drawing a plan for my future house and see no alternative to putting windows into the mix rooms side walls.

I can think of the holes to work though. Those metal absorbtion panels from the Frauenhofer guys work on the hole concept, mufflers do long since, and the acoustic cabine of someone whom I visited lately works great on that basis as well ...

Ruphus

PS: There´s one point about mufflers though ... They work only for small calibers as they can´t absorb LF too well.

...

[The Byre]

The place to ask about Clearsobers and how to DIY then, is on the Studiotips forum.