Help with acoustics in my new bedroom studio

Hi, i will be moving into a new flat in two weeks and have read alot about acoustic treatments in the past months, so now i will try to do my best to get a decent sound in my bedroom:-) My studio is based around a computer and i make some pretty bassheavy music (Drum and bass, trip hop) aswell as mixing recordings i do live for bands (mostly Rock and folk). The (bed)room is slightly irregular as shown in the picture and the height is 217cm. The little "shelve" behind the monitors is from the ground up and 127cm in height and 18cm out from the wall. The floor is parquet and the walls are pine (you know, like in a cottage). Financially i am on a pretty tight budget at the moment, so i will probably not spend more than 200-300 $, but in a few months i will probably be able to spend more if necessary. I will try to take the DIY approach. In the picture i have drawn what i believe is an OK startingpoint, but i am not shure if i have got it right, especially since the room is slightly irregular. The absorbers in the corner i thought of making after Ethan Winers bass trap design, 4 inches of 703 or similar and the smaller ones on the walls 2 inches. I would appreciate greatly any feedback on my project as this is something i have never done before and only read about. Thanx in advance, and i must say i am already extremely greatfull for all the knowledge i have gathered here on this forum! Joachim Edit: updated picture

In a room that size, you can pretty much kill the modal ringing above about 60 Hz with eight 4" thick panels in the right spots. Those spots will likely be the front two wall-meets-wall edges, and a panel across each wall-meets-ceiling edge. You may have to treat that little corner to your back right, so that woudl make two more panels for a total of ten 4" panels. This leaves early reflections and boundary interference. You will have to have your speakers very close to the wall behind them, so I would recommend placing a large absorber in this wall, as thick as you can and with as thick of an airspace as you can... I'm thinking nine 2" panels here, stacked three thick and side-by-side. That leaves the side walls and the ceiling; two panels on each side wall and three on the ceiling with a generous airspace should do the trick. So, we have eight 4" thick panels and 16 2" thick panels... I think you can get this for within your pricerange if you get a good deal.

Wow, thank you, that was alot quicker then i had hoped for. I am not certain i undrestood exactly how you ment i should place the panels in the corners... Do you mean i should place them as in my drawing (across the corner) or in paralell with the walls/ceiling? Also, the shelve behind the monitors, should i make shure that there is no airgap where i place the panels in the corners or is that of no importance? I have attached a sketchup file if that can be of any help.

Always across the corners. I don't think the airgap will be of much importance, but I can't prove it.

Right, then i think i get it! What about the backwall by the bed, would it be a good idea to put some broadband panels there aswell? And the corners there? Also i will buy a new set of monitors, and was wondering if my room is to small for big and bassy ones like the blue sky pro desk/ dynaudio bm6a/ mackie hr824... I read somewhere that you could get problems with big speakers in small rooms. Maybe just fairytales, i dont know:-)

If you're talking corner placement for bass absorption, a panel near a corner but flat against the wall is a waste. Always across the corners. A panel on the wall above the pillows would be a good idea. A panel practically anywhere is a good idea since your goal in a room that small is dead dead dead. The solution I outlined was designed to be the minimum required to get the job done, or as they say in my neck of the woods, git'er dun.

i have made a new drawing based upon your tips, am i onto something here?

If you do that I can almost guarantee the room woudl be as good as fiberglass panels can make it. The only remaining problems are speaker and listener placement, and you still may have some modal ringing below 50 Hz. Regardless, the room will sound very tight.

Great! I will have to do it step by step, as i dont have time and money to do it all at once. So, correct me if im wrong, but the things i should concentrate on first is to treat the corners in front and the walls around the listening position? And i should have as much air between the walls and panels as i can live with? If i get troubles below 50 hz is there anything i could do to tame that? I do some drum n' bass, and there is alot going on around 40 hz in that kind of music. I will upgrade my monitors and the ones im looking at is the blue sky system one or prodesk and dynaudio bm6a. Are some of these to big for my room or is that less relevant when the room is treated? (I can get a good deal on the system one, so im quite keen on those!)

I will have to do it step by step, as i dont have time and money to do it all at once. So, correct me if im wrong, but the things i should concentrate on first is to treat the corners in front and the walls around the listening position? And i should have as much air between the walls and panels as i can live with?

Right on both accounts.

If i get troubles below 50 hz is there anything i could do to tame that? I do some drum n' bass, and there is alot going on around 40 hz in that kind of music.

Two options: pressure devices such as panel traps and Helmholtz resonators or significantly more voluminous porous absorption. Mixing with the door open may help as well. I don't really believe in monitors that are 'too big', except for the situation where you have speakers that are meant to be listened to at a certian distance and you can't practically get that far away in your room.

Ok, then i think it is time to shop some materials! Does anyone know of a rockwool or glava product that matches 703? I tried to look on their websites, but i only got confused, didnt find any info about density, and there were hundreds of different names (or almost:-))

II'm not the expert of sourcing Rockwool, but I think you should look for Roxul RHT40 [pdf]. I also found this company in Norway.

Yes, that is one of the companys i checked out, problem is i cant find information about Kg/m3 of their products. They have something called "lydplater" which translates to something like soundpanels, but i cant find any information about it other than how much heat it can take :roll: i found something else that says it has soundabsorbing caracters, i have attached a pdf file of it, its in norwegian, but maybe someone can get something out of the technical details?

That RHT40 stuff is 3.5 pounds per cubic foot (density). 703 is 3.0. Similar densities of Rockwool or fiberglass should absorb similarly.

Heisann! Regarding Rockwool products; Lydplate ('sound sheet' in english) is 90kg/m3. http://guide.rockwool.no/sw14426.asp Better to use the Akustikkplate. 60kg/m3 and works great. http://guide.rockwool.no/sw14613.asp Comes in aprox 1, 2, 3 and 4 inch size and various colours. Paper facing on one side and absortive glassfiber sealing on the other. Optional side sealing can be ordered in production. It's a sort of dry spray on thing. Not reflective glossy paint. Probably chosen for its acoustic properties. Doesn't look like it'll seal it up 100% though, have taken a bit of precaution just to be safe. Still a lot better than not having it! It's cheap too, about 1/20 of the full price if memory serves me right. picture - these are 5cm boards with the white paint. The usual dense yellow stuff is hidden inside. Cheers, Andreas Nordenstam (Lupo) also in Bergen, Norway PS: Do I know you? :) (small town and all) PPS: Norwegian akustikk article at this brand new tiny little site and mastering op. :)

Halloen Lupo! Joachim here, from Tom's studio! Funny seeing you here:-) Thanx for the tips mate, should have thought about asking you! The walking soundencyclopedia;-) Nice site by the way, really good articles! Didnt know you had a mastering studio, is it brand new?

Hi! >Joachim here, from Tom's studio! Funny seeing you here:-) Hehe.. Small web this is. :) Give a shout if you need any assistance with ordering the rockwool! >Nice site by the way, really good articles! Didnt know you had a mastering studio, is it brand new? Sorta. It's slowly evolving.