Help with a studio deign needed!

Hi all, I am looking for advice in building a studio, I am in the early stages but hurrah, we have secured a venue! It does have some shortfalls, and instead of changing venues to find the perfect venue, we are going ahead. I am hoping in this thread to get a basic idea of the expected potential results. Attached is a floor plan of a section of the church which we are using, the specific room temporarily titled 'multi purpose room'. It is a small space, with high ceilings and double brick. 6.6 metres long, by 6 metres wide, 5 metres high. Floor is a concrete slab. The two doors will be bricked up and 1 new door installed, I expect to go for a purchased acoustic door, at the same acoustic rating that I can get the walls to. The windows need to be kept as is for heritage reasons, so will have to be boarded up from the inside (advice?) They also need to have as much acoustic dampening as possible, as across the road from those windows are the neighbours. Yes its a residential area, but no train or tram lines, no plane route overhead. the ceiling will need to be completely replaced. I will need to choose a location for a air conditioner/ventilation unit. I understand that double brick, rendered both sides will hit an STC of 57 or thereabouts? So the problem areas are, the ceiling, windows, door, and ventilation point. So far my thoughts on how to deal with these are, I believe the ceiling will need to be twin leaf, double layered 16mm plasterboard with green glue. I would assume anything across the windows will need to be the same, perhaps the first leaf across the windows alone, and the 2nd leaf over the entire width of the room, connecting with the inner leaf of the ceiling, and the 2 other brick walls. The door I will just pay the cost of a commercial acoustic door. The ventilation I have not researched much on yet. So whats the room for I hear you ask? My personal passion is mixing, sound, composing for screen, and I write dance music. however we also want to record in this space, to a moderate quality level. acceptable quality equipment, with a quiet room is our goal. We will consider a dedicated vocal booth. We may consider splitting the room into two for a mix space and a live room, but would prefer to go for a single room design to reduce cost of building interior walls. I use PMC TB2's. I don't have the matching sub, but will be using a cheaper one at some stage. Other people in the facility want to record in the space, and we want to aim for a high quality on internal acoustics/soundproofing, with a single small room design. These monitors should not be soffit mounted due to the rear firing transmission line port, so I can't use any of the mix room designs I've found on the John Sayers forum, they love the soffits there. Can anyone link to any starting point designs for mix rooms? If I am going to be building a new plasterboard wall across the windows, I need to know if I should put it on an angle to remove the parallel wall factor there, and if I do, should I be doing it with any other walls. This is a first time project for me, and any advice would be highly appreciated! If I can do it, I want to sound proof this enough to be able to use the space late at night, and even during the church service in the main hall. I know this may be impossible, but I'm going to try get it as close as possible. Cheers for any support you can give! Evan

Perhaps for a 2 room design this one attached that has been linked to before on this forum could work, however as I can't soffit the speakers I am stuck!

Don't get so hung up on the soffit mounts, just leave them away and set your monitors on stands behind the desk - proportional to your listening position. The walls shown with soffit mounting can simply be boundary walls, or perhaps with slats and absorption as deemed necessary after during pre-tuning. Even speakers with rear ports can be soffit mounted to advantage - read a little more on the subject (include the theme "infinite baffle"). See John's "Recording Manual" on the Construction - Speaker tab, and imagine creating a guide for the rear port down into the hanger compartment. Also check out his Small Studio Post in the design section. P.S. We really should say In Wall Mounting or IWM as the term Soffit mounting is wrong and applies to a time when the speakers were indeed mounted high up near the ceiling angled down built into a proper soffit. This practice has long gone out of vogue. In a forum that likes to be accurate and provide good known-to-work methods and proper terminology (i.e. MAM MSM), I suggest the term Soffit Mounting should not be further propagated.

note taken on the word soffit. Interesting point that the same designs can be utilised, just not set up to gain the same gains in wall mounting are designed to provide. The manufacturers have personally recommended to me that I don't try in wall mounting. I can see it would work fairly well with less effort put into huge mass on the wall they are in, and I can see there would still be benefits for it to pass through a path way of insulation like in standard in wall mounting design, however transmission line speakers are essentially this design inside the cabinet already, so I wouldn't both putting too much effort into this. Essentially you are saying the angles would all still work though? makes sense. Can anyone confirm that double brick, rendered both sides would give an STC of 57? I don't remember where i got this figure from, i doubt its accuracy.

double brick rendered is likely close to STC-57. check out the nrcc reports on http://www.nrc-cnrc.gc.ca/obj/irc/doc/p ... /ir586.pdf

Xen Ochren wrote:

Can anyone confirm that double brick, rendered both sides would give an STC of 57? I don't remember where i got this figure from, i doubt its accuracy.

I can confirm that there is a good chance that if it is not done with a very meticulous eye for detail, it may not achieve this level of sound transmission loss which will result in the transmission losses being affected...and these are the ones we consider more than STC. Factors Affecting Sound Transmission Loss: http://www.nrc-cnrc.gc.ca/eng/ibp/irc/c ... t-239.html

thanks for the links, I will read them thoroughly asap. so the double brick is not yet rendered, I will be organising for this to happen myself and therefore have some control of the quality. I have just realised that the outer wall, the one with the windows and therefore the needed plasterboard wall across it, has another problem. The brick is double brick, but with an air gap in between the 2 layers. the gap is about 10 cm's. This means with my current plan of an interior wall providing the 2nd leaf and helping soundproof the windows, I will in fact be adding a third leaf which is naturally to be avoided. I don't know what to do about that wall...

"I will be organising for this to happen myself and therefore have some control of the quality. " The rendering isn't specifically the issue...it is the bridging that can occur when the mortar is placed and falls into the cavity, which makes a bridge between the exterior and interior block wall. That is the issue, and trust me it will happen since this is a difficult thing to do with out some preparation. Typically it would be adding rigid insulation in between the block to ensure this bridging does not happen with the falling of sloppy mortar. It is part of this type of construction...and you need more than one pair of eyes to cancel the effect.

one consideration - plug the window and test the isolation as-is. a lighter inner isolation wall in conjunction with the heavier exterior walls (even in a triple leaf formation) may be feasible depending on your ultimate isolation needs. as Brien points out, anything bridging the walls will cause an immediate loss in isolation. if you have access to the space between them, there may be options to fill that gap to make a single leaf if necessary but do the testing first.

great points thanks guys! bare with me while I try to fully come to grips with this? if there is bridging, doesn't that make it a single leaf again? so the air gap already built into that outer wall is useless, and the entire thing acts as a single leaf, the perfect thing to build a 2nd leaf of plasterboard with air gap across?

Or it would as you just said need to be filled... I want to avoid triple leaf as I write dance music and its mainly the constant doof doof bass that would annoy any neighbours. As much of that that can be contained the better.

the bridging wouldn't help... unless you can fill in substantially (sand, concrete etc) you'll just have pockets... that said, if you have decent isolation for the most part with the 2 brick walls, then adding a third leaf inside which is 2x 16mm drywall on steel framing, the inner walls may provide a lot of the LF absorption you need - but then you also need to consider the floor and ceiling in the equation to be sure. another consideration - your monitoring - you're doing this electronically ? if so, maybe reasonable monitoring levels during the recording and mix process and just a few loud tests periodically could put you where you want to be without a lot of headache (for you or your neighbors).

hmm i think just filling it with something would be the easiest. Will something as simple as sand change it from 2 leafs into 1? we also will be recording in the space, so yeah, drums. I think my approach will be to make the outer leaf/original structure of the room as good as possible first, then to have a seperated inner room, made entirely of twin 16mm firecheck and green glue, connected only through the concrete slab floor. I don't yet have a design planned for this inner room. My problem here is the door, and the ventilation, as these will effect the outer leaf. I'm a bit stuck on how to proceed! Its hard to even start testing the current space, as I know the ceiling is almost non existant so will give low results. I'm trying to estimate what the lowest STC I will be able to achieve for walls, ceiling and windows, so I know my weakest link, and don't buy an acoustic door of a higher rating. Those doors aren't cheap!! If I had my internal design sorted I could progress further. Most designs on this website show a control room with angled walls. I only need one live room, and one control room, or perhaps a single room good for both. Can anyone link to any designs of these off the top of their head? In the meantime i will keep hunting myself. Cheers Evan

i think the example design you posted with some tweaks on the sizing should be nice and if you can get to 3.5m on the ceiling or even 4m you can use that space overhead to add trapping and free up some floor space. also, consider your working mode - you're not likely to be recording drums during a service etc so it may be that once you measure the existing isolation and do some testing with rubber and metal hammers to determine how much structural transfer you have, you'll be better able to arrive at the things you need to do to isolate your space.

thanks. is there a tutorial or thread here on how to test rooms before you start building? seems like a tricky thing to do. are there any single room designs around? i've hunted but couldn't find. I expect single room would reduce the cost massively as you have less wall distance, less doors etc

on gearslutz studio forum one of the stickies there is an excellent tutorial on using REW to test your room.

do you mean this link? http://www.gearslutz.com/board/studio-b ... 2-1-a.html im not talking about testing internal acoustics, but sound transmission loss outside the room before construction starts, to help in the design. Also has anyone seen any interesting single room designs for a room near my rooms dimensions?

Thanks to Guilfo and others for support answering my questions! I think I will stop asking questions here as maybe I have been too vague in what I am hoping to discover. I am starting a new thread with some clearer questions. Mainly, i'll worry about sound proofing once I have a basic design happening. thanks again guys!

to do the isolation measurements - a speaker system capable of driving 110db or so with sine sweeps, pink noise, and bass-drum tracks and a sound level meter. make notes in the room and all areas around inside and out to map out the levels. use rubber and metal hammers and tap (or have an assistant do it) and note the amount (subjective) of the structural transfer.