groundwork (drawings inside)

Steve, Yes, I'm fully aware by the continues mass/air/mass. Here's the roof plan. Again, I apolgize for not knowing all the names of the different parts of the puzzle. I only just learned them in Dutch... :D Coen

The stuff in the drawing you labeled as "no idea" would be called "fascia" in english - basically means "for looks only", root word "face" I believe. Ceiling - you're planning an inner frame with gypsum for the inner leaf, resting on your inner wall? Steve

What you see here is the outer shell of the studio. The inner ceiling is attached to the inner frame and will have a gypsum/mdf/gypsum sandwich just like the inner walls. The whole inner frame will NOT touch the outer structure in any way. Lemme draw a pic. Coen

like this:

Technically, there's a chance for flanking through the floor... That's why some people opt to do a true floating floor. However, since you're dealing with airborne sound, you probably don't have to worry about it too much. This is per my local acoustic engineer who settled my "to float or not to float" conundrum once and for all.

Steve, First, I did a search on this forum for "flanking" and also googled it, but I'm not 100% sure I understand exactly what flanking is. From what I understand, flanking is sound that's transmitted through flanking walls/floors, eventhough they're not connected to eachother? I learned somewhere that concrete is worse for flanking than wood, but that doesn't learn me much as I don't know exactly what flanking is... At this point I can still opt for a fully floating floor, but I doubt I really need it, as still room will never house a full band or drumkit. Thanks for your time, I appreciate it! Coen

Connect two cans together with a string. Pull tight. Get a friend to talk into one can while you listen with the other. That's flanking basically.

Thanks Sharward, but I still can't relate that to my construction. The only connection between mij concrete floor and the outer leaf is sand. Coen

Coen, in your case you should be fine; just be careful not to connect any structural pieces that form the outer leaf to any structure belonging to the inner leaf. Your slab is already "almost floated", it would probably even work for drums in a pinch... Steve (Only link I have for a paper on flanking is about 300 pages long - just follow the simple advice above and save yourself some time)

I still want to know what flanking is and will do some more research. I'm sure I'll find out one day.. :D Anyway, tomorrow I'm gonna make the roof and I'll post some pics. Thanks again and have a great weekend! Coen

Found this on Google search: Flanking: The transmission of sound around the perimeter or through holes within partitions (or barriers) that reduces the otherwise obtainable sound transmission loss of a partition. Examples of flanking paths within buildings are ceiling plena above partitions; ductwork, piping, and electrical conduit penetrations through partitions; back-to-back electrical boxes within partitions, window mullions, etc. Hope this helps.

I guess what I described was structure-borne noise... :?

Thanks Kendale! Well, it's raining like hell here so I can't work on the roof.... bummer...

Well, It's 11 months later and I'm picking up my studio building again. I had 2nd and 3rd degree burns on my knees from the damn concrete that took me out a couple of months. Turned out that I'm extremely allergic for some kinda acid that's in concrete. From now on I'm known as the guy with the unfinished studio and the ugliest knees in the world.

Agh!!! Sorry to hear that! Yes, concrete burns do happen -- you're not "special" in the sense that it would happen to anyone who wasn't careful and wearing proper protective gear. Paul Woodlock learned that lesson the hard way with a really bad burn right on his bum!! :shock: He even posted pictures of it! :lol: Yet another reason I contracted out my main slab pour... :roll: Ow. --Keith :mrgreen:

Keith, The surgeon said he never saw something like my knees.. concrete burns that is. I used some cardboard, but clearly that wasn't enough. I won't post any pics, if I'd do so, I'm sure the forum admin would close this topic... hehehe Coen

Anyway, The outer leave is ready now and I can start building as soon as I have a final floorplan. Here's the current situation: Requirements: Recording vocals and electric guitar (no insane levels), practising vocals and guitar, occasional mixing. No drums or a whole band will rehearse or record in this room. Eventhough the room is built in a residential area, the closest house I have to worry about, is 80 ft. away. My direct neighbours are older and probably a bit deaf and assured me they’ve never heard me play (I did record and practise in this room last year). I was quite surprised how little you could hear outside the (yet to be) studio. In my own house you can’t hear anything, unless I turn up my Marshall (mine only goes to ten). Since this room is rather small, I’m planning to make a vocal booth with a heavy curtain on a rail in one corner of the room. So if I don’t use the vocal mike, there’s no vocal booth. Noise from the computer fan is not an issue. Roomsize and construction: Inner size: W :312cm (122.8”) D: 282cm (111”) H: 256cm (100.78” Outerwalls are rendered bricks (see pics on previous page) and two layers of OSB on the roof. The reinforced concrete floor does not touch the walls, so I pretty much decided not to go with a floating floor. I’ll use a 2x3 wooden frame with gypsum sheets and rockwool for the inner leaf. I can't soffit mount my monitors as those are powered speakers and have a weird angle. All I gotta do right now is decide what floorplan to use and start working. Suggestions are more than welcome! Coen

I would make the room bigger inside, and then consider treatments after, instead of 'locking-in' to the smaller size... It's not like you have a huge area here, at 10.23 feet long, 9.25 feet wide, and 8.4 feet tall. So, it's possible -- from what I think I'm inclined to believe from Rod's book -- that your not gonna make it great by simply by angling walls. In other words, the 'smallness' is more of a hindering factor... and angling walls will only make it even smaller. Maybe I'm misunderstanding this, so I hope Rod can step in here and explain what might be better for you.... K

Inner size: W :312cm (122.8”) D: 282cm (111”) H: 256cm (100.78”

If you search/browse through the Studio Design part of this forum you can confirm both John and Steve mentioning this many times: In a small room engineer always faces the short wall, so your Design 1 wins. You may also want to post over there in Studio Design as John is the design guy. As Luftweg brought up you are facing a similar delima as I... splay or not to splay because of size of room, loss of square footage... I still do not know what I am going to end up doing. I'm going to keep an eye on this thread to see which way you go. I recently brought the topic up with Sharward and he's going square although his room is more for rehearsal and isolation. You can also splay the room like <> ... to lazy to draw... that's splay front half and back half of room so you'll end up with a diamond kinda shape and keep the side walls splayed by 12 degrees. There are many options. Make sure to review Johns plans on main part of this web site. Don't know if you read this before... your listening position (sweet spot) should be 38% back from front wall. That's where you could start the equilateral triangle from, your speakers don't actually have to be in the corner. This is arguable, many different layouts have been done. You going to want some room for absorbers behind the speakers since your not soffit mounting. Also pushing your listening position closer to the front of room will give you more "strectch and stand" room. Are you sure you want to use 2x3's and not 2x4's... you didn't say how many layers of drywall you are putting up, plus your ceiling. Also noticed on previous post your planning on 2x4 ceiling joist for 9.25 feet wide.... if that's still your plan, that won't work you need to use 2x6 for that span. Marc

Thanks for the replies! Luftweg, from what I've seen, John comes up with angles wall designs for pretty much all rooms, including the small ones, but correct me if I'm wrong... I also need some space in those corners for the air in-/outlets. Those are 100-150mm. If I'd make the room square, the sidewalls would have to be moved further inwards. Marc, I know about the orientation of the speakers, but the confusing thing is that I've read the opposite (on other forums though) too. The more you read and learn, the more questions you have. I considered the diamond shape, but takes away ALOT of space. I'm planning to use two layers: one layer of drywall and the other something similar (different thickness though) of a material that's called fermacell over here, which is pretty much like gypsum, but has more mass. As most people I'm on a budget and the price jump from 2x3 to 2x4's is quite high. A friend of mine is an engineer and he calculated 2x3's would be just fine. I will use 2x6 joists for the ceiling though... Coen

Hey guys, just a quick question: Eventhough I did search on the forum, I'm still NOT sure what " mud" is... I'd appreciate it if someone could explain... Coen

It's drywall joint compound.

thanks, jammin dad! I was always under the impression that you'd had to caulk all the layers. So what I understand, you "mud" all the layers except the last one, which you caulk, right?

I was always under the impression that you'd had to caulk all the layers. So what I understand, you "mud" all the layers except the last one, which you caulk, right?

Perimeter of all layers is caulk (well stuff with backer rod then caulk). That would include all corners: wall to wall, wall to ceiling and wall to floor. All seams of drywall in a single layer of is specifically: Mud (drywall joint compound), drywall tape and more mud (all applied at same time)... then sand to make flat for next drywall layer OR mud & sand 3 times if it's the finish layer. Only exception is finish corners for appearance sake can be stuffed with backer rod, caulked (raked back a bit for), mud, tape and more mud so your left with a good looking corner to paint. See Rod's comments on this in the following... In reference section the 3 links to caulking threads: REFERENCE AREA - Useful threads/links Note Sharward has decided to caulk a few of his drywall seams instead of mud... the recommendation from all I've read is mud, however I could see an argument that caulk in a seam may fill the seam better and is more dense which might make is better for isolation over all. :roll: Also in regards to:

Marc, I know about the orientation of the speakers, but the confusing thing is that I've read the opposite (on other forums though) too. The more you read and learn, the more questions you have. I considered the diamond shape, but takes away ALOT of space.

I know if John or Steve were to kick in here they would say face the short wall. Yes larger CR's can face the long wall but the recommendation in a room your size (and mine) is to face the short wall. Square footage lost to splaying with a diamond shape would be less then that lost to splaying side walls entirely one way. The wide part of the room would be in the middle and not the back making it feel bigger. Splay is 6 degrees per wall, 12 degrees off making them parallel or 1 foot in 10. Let's say the long walls are 10 feet long for an easy number to work with and see attached pic. I AM NOT saying this is the best thing for acoustics in CR alone with regards to reflections, but it would definitely break the parallel walls up and max out square footage, especially for a single room studio. I've seen a few of johns designs namely "paddy2" and "studio in a container" where the room shape is similar to the "diamond" but the splay comes from a slot resonator. AND take a look at this: http://johnlsayers.com/Studio/Pages/Giles.htm Marc