Help me treat a difficult room

Nebulous

Daniel
Dec 14, 2003
4,536
3
38
Brookfield, VIC, Australia
G'day again

So lately I've read alot of the threads we have here about room treatment, I've read the links within them and I understand the crux of it: kill all first, early and direct reflections + bass traping= the shit.

My main reason for wanting to treat the room is not for the vocal and guitar recording I do here, but more for the mixing I try to do.
I've noticed lately that my high and mid frequency detail is not improving much, and due to the flutter echoes and definate comb filtering, I'm also struggling with depth perception and creation in mixes.

Knowing that is all well and good, untill I take my eyes away from the screen and have a look at my room.
Being previously built and used as my sisters beauty salon, it isn't your typical bedroom, rehersal room or studio control room.

Here's my dilema: room shape and fixtures. These pictures will demonstrate it better than I could with words.

From the main entrance door:
DSC00004.jpg


From the unused end of the room:
DSC00005.jpg


A closer look at what is directly behind the mixing position:
DSC00007.jpg


The mixing position:
DSC00008.jpg


In experimenting with some moderate volume music, I've noticed the following things:
- Due to the size of the room, the only bass concerns I can find are that I get about a 40-70Hz buildup in the corners (near the door, when it is shut, in the corner of the kitchen and the two walls at the far end of the room).
- Due also to the size of the room, I don't feel there is a huge impact to the mixing position from the bass building up at the corners, though I am open to being proven otherwise
- Flutter echoes and comb filtering occur at my mixing position
- My monitors are not at the ideal height, though the sound of them at the correct height is quite fatiguing with the presence of the previously mentioned flutter/ comb filtering.

What I've considered is to eventually treat the corners, but as mentioned before, my main concern is the direct mixing position.
Would it work if I was to build a "dead room within my room"? That is, at either sides of my desk errect a pannel that follows the depth of the desk, then attatch another pannel across the top of the tow sides to create a dead ceiling.

That idea has come about due to the obvious large amount of surface area I would have to cover if I worked the room as a whole, and the fact that I am pretty stuffed in creating a dead ceiling surface due to the lights and central heating/ cooling ducts right above where I sit.
Moving my desk to the other side of the room will not really make a difference, there are lights and ducts there also.

Some things to note:
- I've measured my listening position and found that I am at the 38% distance of the width of the room
- The room is 3.5m wide, 5.5m from the kitchen bench to the end of the room, 7m from the entry door to the end of the room.

Will my small dead space idea work?
 
The first thing I would do is set the desk up to face down your room length-ways. That is, close to that window with the kit in the corner. Make sure the mix position is at 38% of the length of the room, not the width. The sides should be as symmetrical as possible to retain optimal stereo imaging, so you want to be at 50% of the width of the room.

The tiny room within a room is a bad idea because 1) all you will do is create a small resonance chamber and 2) you effectively limit the size of the room in the creation of room modes, meaning that you will get more severe acoustic problems if anything. The room within a room only works when designed from the ground up, is done well, and aimed at increasing sound isolation rather than improving acoustics within the room itself. The way to get around treating the ceiling is to make a cloud - essentially just hang some insulation panels off the ceiling using chains/strong plastic ties or whatever. And keep the monitors away from nearby surfaces, such as that wall you have them right up against. That kind of thing tends to increase modal ringing in the lower frequencies.
 
The first thing I would do is set the desk up to face down your room length-ways. That is, close to that window with the kit in the corner. Make sure the mix position is at 38% of the length of the room, not the width. The sides should be as symmetrical as possible to retain optimal stereo imaging, so you want to be at 50% of the width of the room.

The tiny room within a room is a bad idea because 1) all you will do is create a small resonance chamber and 2) you effectively limit the size of the room in the creation of room modes, meaning that you will get more severe acoustic problems if anything. The room within a room only works when designed from the ground up, is done well, and aimed at increasing sound isolation rather than improving acoustics within the room itself. The way to get around treating the ceiling is to make a cloud - essentially just hang some insulation panels off the ceiling using chains/strong plastic ties or whatever. And keep the monitors away from nearby surfaces, such as that wall you have them right up against. That kind of thing tends to increase modal ringing in the lower frequencies.

Hm, will give some consideration to moving the desk. Will be a pain as I'd have to move alot of the excess furniture in here, not sure if it would really make the most of the space in here, ie, it may make it too difficult to move around the room and I will have to check that there are enough power points over on that side of the room.

Just to clarify my initial idea, the "room" wouldn't be sealed or solid. Just thinks of the exact pannels that you've made, wooden frames with faom inside. I'd hope that wouldn't create any modal issues, but one thing I did consider with that idea is that the rest of the room would still impact on the reflectd sound, so may not be that efficient.

Ideally for what I need, price vs efficiency and the fact I may be moving (with or without the parents) within a year I'd want something simple that wouldn't leave holes in the roof or walls.

Have you figured out your ceiling yet, Ermz?
 
Well you have to prioritize. Work out whether being able to move around comfortably is more important to you than having a more acoustically ideal environment. You already know the no-compromise approach I took in here, with barely any room to do anything other than produce audio :).

Definitely can the acoustic foam products and get into rockwool/fiberglass insulation land. They are much more efficient to much lower frequencies for less volume.

As far as my ceiling goes, I'm waiting to get my hands on a staple gun to get some sound acoustics foam up there. It's the only compromise solution I can really do in a rental property. Unfortunately a cloud isn't an option.
 
I feel you about the cloud. It's my biggest problem too, hence my original idea.

I've given abit of thought to the room arrangement. If I work it right I could actually keep alot of the space, and that way the walls would be easier to treat, and as you mentioned would create symmetry around the desk.

I'll keep at it.
 
Hm, just spend some time measuring and drawing it out on paper. It could actually work, even with all this excess crap in here. How heavy are those fiberglass batts? I've thought of a way to get some up at the other end of the room, but it would really depend on their wieght (with no frame).

Do you know of a good place to get them in Melbourne, Ermz?
I'm really glad I asked here, the more I think about it now the more I could make it work.
 
Depends which batts you're after. Some of the less rigid ones like 36kg/m3 aren't too heavy, but the ones in the 96kg/m3 range can start fighting a bit.

Your best bet may be to get Insulco's Semi-rigid product, which John Sayers seems to like. We've been trying to source Tontine Acoustisorb 3 for about a year now with no luck. A lot of these companies are very hard to get in touch with and work out where to get the product from.

If you manage to source Acoustisorb 3 here in Melb, tell me!
 
Haha, nice.

Bit of an update:
DSC00013.jpg


I pulled my finger out and rearranged the room today.
It's still not 100%, obviously you'd expect that in an untreated room. The flutter echoes are still there (you can hear them from behind clearly) and the proximity to the walls now means there are some modes building up in the lowend to an extent that I didn't expect (still bearable for the moment).
On a positive note, there are some good differences. The sound is definately more direct this way, it's already help in hearing the depth and verb that I was struggling with before and the imagining is better again due to the symmetry of the room now.
The monitors are now also higher up. Still getting use to it, but they are defiantely more focused in the mids now.

In setting up the desk position, we put some of the cluttered furniture up against the wall and glass doors, so the desk and my seating position are just about at the 38% mark.

I'm looking forward to those pannels going up now. I can only imagine how much better it will get.

Thanks for the kick up the ass Ermz :p How much is the Tontine going to set you back?
 
That's looking a lot better dude. It will get a lot better after the panels. Much more significant than upgrading monitors if you can believe.

The Tontine will be around $15 to $20 per trap for us I think. We're considering buying in bulk as we want to kick the business off again and we finally found the stuff to use. FWIW the Acoustisorb 3 is fairly rigid and easy to work with.
 
That's looking a lot better dude. It will get a lot better after the panels. Much more significant than upgrading monitors if you can believe.

The Tontine will be around $15 to $20 per trap for us I think. We're considering buying in bulk as we want to kick the business off again and we finally found the stuff to use. FWIW the Acoustisorb 3 is fairly rigid and easy to work with.

Fuck dude, you've done the groundwork and beta testing, are you taking orders yet? :p

I think I'll be needing 6-8 of them for the walls as a minimum. I'm not 100% sure how far into the room I want to/ can afford to be lining pannels against the walls.
I'm thinking, at least as a minimum for the moment, of treating the room as two sections, and leaving the kitchen/ open area untreated as the "live end", especially since the fittings and furniture in the room would make it a bitch to try fit more pannels there.

How wide and high are your pannels?
 
The current panels that are in my room are 1400x700mm or there abouts. The depths on the broadbands are 75mm and the bass traps 150mm.

We're still trying to get the new wave of traps sorted but it does seem like it may be a few months before we get the first batch done. Still trying to look at the best construction methods. FWIW we'll be selling off the ones I have in my room almost straight away after the new ones are rolling out.