New Studio Build, Los Angeles CA

Hell out there! My dream is finally coming true to be able to build a commercial room. I have been searching around for sometime now trying to find an answer to some of my concerns. Hard to get a final... I guess if I searched longer I would be able to find it. So...I am planning a build in a warehouse that is 2000 sq' (23'x90'). I'm running Pro Tools HD2 with a Control 24 console. I am plannng to soffit mount these awesome KRK V88 monitors (I also have two 12" subs to go with each...wondering if I can soffit the subs too, hmmm?) I have neighbors on both sides sharing what I believe is a sheetrock+Insul+sheetrock wall. I will be building a 27'x18' outer room (1) Layer 5/8 sheetrock+Insul for the outter leaf, with the inner rooms insul+ (2) layers of 5/8 sheetrock. My concern is if I should spend the money on the RCIS for the inner leaf. I will be working during business hours on ocassions so isolation is pretty important. I will use 2x4 timber with fiberglass (r-13) in both walls essentially creating a Mass+Air+Mass system. I have enough space to afford a nice air spring gap so...can anyone pleeeaaasssee tell me if it is worth the extra cost of the RCIS or better yet is it even necessary in a M+A+M wall assembly? I have included file attachments of the floorplan and the 3D sketchup. Thanks for any input. I am still tweaking the 3D model working on the interior treatments, ie traps, cloud absorbtion etc. Also the ceiling assembly isn't done but some overall support in the total design would be great too. Thanks guys. Also some advice on the interior acoustic treatment would be greatly appreciated.

can anyone pleeeaaasssee tell me if it is worth the extra cost of the RCIS or better yet is it even necessary in a M+A+M wall assembly?

Simple answer? No. Not necessary. It will not gain you anything at all. RSIC clips are designed only to decouple the drywall on one leaf. If you have a separate frame (which is what a properly built "MSM" wall implies), then the leaf is already decoupled. decoupling it again won't help. Forget the RSIC and save yourself some money and space. However: I also noticed that you are splaying the inner leaf walls in your CR, but you are splaying them the wrong way! The room should be WIDER at the back, not narrower. You might want to fix that. Your floor plan and your SketchUp model also don't match: one of them is not to scale, and not correct! The floor plan shows a square room with the listening position in the exact geometric center. It's hard to think of a worse layout than that! But things look better on your Sketchup model, so I'm hoping that's the accurate one... :) - Stuart -

But things look better on your Sketchup model, so I'm hoping that's the accurate one...

Stuart thank you for the response, the Sketch Up is the more accurate one. I kind of left the floor plan and started the Sketch up design based on the same dimensions but never went back to fix the Smart Draw plan. I exported a jpeg so the scale is definitely off. I did finally get a final answer today... I figured that was the case on the RCIS with a "M+S+M" wall system but thank you for your timely response. I also realized that I should have angled the walls a little different after speaking today with a local studio builder. One thing I am unsure of though is my plans called for (2) layers drywall outside leaf and (2) layers inside leaf. He is suggesting (1) 5/8 Drywall + (1) Sound Board Insul Sheet + (1) Layer OSB 1/2" Inch on the outside and then (1) layer 5/8 Drywall + (1) layer sound board inside. He seems to be right as the differenet materials that the sound will encounter is better but I am waying the cost as well. What are your thoughts? Thanks again.

One thing I am unsure of though is my plans called for (2) layers drywall outside leaf and (2) layers inside leaf. He is suggesting (1) 5/8 Drywall + (1) Sound Board Insul Sheet + (1) Layer OSB 1/2" Inch on the outside and then (1) layer 5/8 Drywall + (1) layer sound board inside. He seems to be right as the differenet materials that the sound will encounter is better but I am waying the cost as well. What are your thoughts?

Your original plans are just fine: 2 x 5/8 drywall on each leaf is excellent. Yeah, by combing materials of different density you can theoretically help to flatten out your coincidence dip and do other exotic things that might minimally improve isolation if Venus happens to align with Mars at sunset on Christmas eve (:)), but frankly the slight advantage of mixing dissimilar materials just isn't worth the hassle and extra cost. And for that kind of wall the coincidence dip is so far up the spectrum anyway that it hardly matters how deep it is. Your real issues are down at the other end of the spectrum, in the very low frequencies, where using different materials has no useful effect at all. The general consensus here is that it isn't worth worrying about. Lots of extra hassle/cost for barely measurable effects in the wrong part of the spectrum. Just go with the cheapest most dense mass you can lay your hands on, and 9 times out of ten that is going to be plain old 5/8 drywall. Sound waves don't care how much you paid for the mass! Simply adding an extra layer of 5/8 will way outperform that sandwich of strange stuff, and probably cheaper, too! Also, I would NOT consider using 1/2" of anything in an MSM wall, and certainly not 1/2" OSB! Too thin, to flexible, too high a resonant frequency, too low a mass. Bad idea. Thin stuff is not good (unless it is really, REALLY dense, as in steel plate or lead sheeting, which are great, but the cost is just a tad higher.... :) ) So I'd forget the 1/2" OSB thing, right away! No use. Get mass, get density, and get it thick. So just go with your original plan of two layers of 5/8 on each leaf, and you'll be fine. Now, if you REALLY want to make a difference with an exotic sandwich, then add a layer of Green Glue between your two layers of drywall: that stuff actually will make a worthwhile difference, much better than mixing types of materials, and it will be in the right area of the spectrum. - Stuart -

Cool... I was a little concerned about the extra cost, plus from all of my reading here I thought it was best to stick with the double 5/8 SR. We have redesigned the room layout though. I am posting a couple of pics that he did, if you would, kindly give me your feed back as to what you think of the new floorplan. I am a little worried about the angle of the front wall, I guess the software that they used to calculate my monitors gave them those angles but it seems real narrow. My monitors are mid-field but I have added two 12" subs (one on each side.) I would hate to be sitting in the back of the room and the sound feel squished or canceling or something. I don't quite know about this issue. Another minor concern I have is do you think Plexi-glass is ok over glass. I think we found a company that offers 1/2" plexi really cheap or does the acrylic vibrate too much? Thanks Stuart.

if you are concerned with the cost (and plastic will not work for your glass) - you might consider reducing the real glass $150K windows to something smaller - say 5' w and 6' tall maximum. also the angles are not symmetrical or steep enough on the control room. you need those side walls at 15 degrees if you're going with a massive plate glass wall like that. the spread between the monitors also have to be wide enough to accommodate your console in the right position, support your monitors, and provide enough baffle to extend the speaker into the room smoothly. each on a 30 degree angle (forming a 60 degree isosceles triangle). if you are going to mount the video monitor on the front wall, you'll want a big one there as well. minimum 55". while you're at it, you might consider 5.1 capability for the room. also, you said in your original post you have 23x90 but you're only using maybe 1/3 of the space for the studio?

Like Glenn said: you have a huge amount of glass in that design. That is going to cost you a huge amount of money, and will most likely cause acoustic issues with the room. Glenn is absolutely right (like usual! :): You might want to give some serious thought to reducing the amount of glass in that design, (unless you have a bottomless bank account!). Regarding your questions on the Soffits: You are right about the angles on teh front wall: it does not look right to me, but it's hard to tell with only the picture. Also, I'm not really understanding the design concepts you have there for the soffits: What is the gray colored stuff above the soffit panels, going diagonally? Is that carpet? Cloth over insulation? Something solid? Something soft? From the picture is also looks like the speakers are poking out of the soffits, and are tilted down at some angle while the soffit is vertical. I wouldn't do that. The purpose of the soffit is to act like an extension of the front panel of your speaker. It is supposed to be co-planar with the speaker front panel, and therefore must be at the same angle. If you need to tilt the speakers down to get correct geometry, then you you have to tilt the entire soffit panel to the same angle. You can't just angle the speaker and leave the panel flat. That leads to another question: Why do you have the speakers so high up the wall? The general rule is to mount you speakers at the same height as your ears, which is roughly 1.2 m above the floor for most people (that's the height of the acoustic axis of the speaker, not the top or bottom of the speaker cabinet). Your picture shows the speakers to be mounted much higher than that, and there don't seem to be any obstructions in the room that make you put them that high. What is the reason for that? Can you change that, and put them at the recommended height? There is also the issue of width: the soffits aren't wide enough. They should extend quite a distance to each side of the speaker cabinet, at least 50cm or so, and more if you have the space (or if the speakers are already large). It looks to me (Glenn already said this, too: I'm just repeating it) that your geometry is off for the front end of that room, particularly the speaker / walls / listening position. You might want to look into that some more, and re-design it to follow the normal recommendations better. Finally, there's the issue of your subs: Do you really need two subs in that room? I can't see that there will be a need for that, especially if you are soffit mounting the mains. Also, with two subs spread apart you tend to create a null "trough" down the center of the room. I think it would be better t go with just one sub in the middle, or if you really have to have both of them, then I'd put them right next to each other in the middle of the front corner. They should also be on the floor, not part way up the wall. - Stuart -

Hey guys sorry for the long delay in responding we have been busy at work making the changes that were suggested and buying some materials. I have purchased all of the insulation :mrgreen: HVAC system and getting closer to buying lumber. Gulfo thanks for your response as well. I took your advice and decided to check around at the ReStore (Habitat For Humanity) locations and boy oh boy was it my day :yahoo: . I found (2) 1/2"x50"x95" sheets of glass for $4 a square foot. I also got two smaller pieces of the same stuff for the small ISO room. I am attaching some new pics based on the recomendations you and Stuart made. The last floor plan and the rendering weren't all the way complete so some of the stuff had to be cleaned up as relayed to me by the designer. So the lines around the speakers weren't supposed to be there on the plan and the gray stuff on the wall was part of the design and absorber treatment. Since removed from the design. As far as the other points: We brought the subs together on the floor behind the console. Created a little recessed design. The front wall will follow the same plane as the monitors they weren't supposed to be sticking out but the software for some reason wasnt allowing it to change it too easily, but has been fixed though. We placed the monitors higher because we are angling the front wall to get the right downward angled direction of the monitors. I personally like the monitors up a bit higher asthetically and I like to stand and listen while I a m mixing a lot of the time, I also work on tracks while standing quite often as well.

It looks to me (Glenn already said this, too: I'm just repeating it) that your geometry is off for the front end of that room, particularly the speaker / walls / listening position. You might want to look into that some more, and re-design it to follow the normal recommendations better.

Yeah the geometry was off, I noticed that too when he sent me the floorplan. We talked about it and made the changes, but I still feel like the angle of the monitors is too narrow. I haven't yet calculated to see if its at 30 degrees yet but I will tomorrow. We also did gain more room on each side of the monitors. Here are a few pics of the changes. Hey shouldn't we have some sort of diffusor on the rear wall of the control room. He designed it to have the one from the side wall continue around the back wall but it seems it should be much bigger to me to keep a little bit of " deflected liveness" to the room. What are you expert opinions? By the way I will be adding baffle traps in the back corner.

You soffits look like 45 degrees... Also the back corner should be used for trapping. The sub looks centered, assuming your designer has calculated this as the best position, you should verify this... How are you going to use the speaker soffit space for trapping if they are sealed? The step angles on the treatments in the live room can be flattened to say 15 degrees instead of 45 or so. Ceiling clouds should be angled.

You soffits look like 45 degrees... Also the back corner should be used for trapping. The sub looks centered, assuming your designer has calculated this as the best position, you should verify this... How are you going to use the speaker soffit space for trapping if they are sealed? The step angles on the treatments in the live room can be flattened to say 15 degrees instead of 45 or so. Ceiling clouds should be angled.

-Yeah man I looked at the soffits and they still seemed narrow to me. I think he has the angles at 39 degrees instead of 30, still need to tweak that. -The back corner actually will have trapping. Do you think that both back corners should have trapping?? We started changing the design a little to move the door up some to trap the other corner as well. What are your thought? -The subs on center was a suggestion that Stuart made.

Also, with two subs spread apart you tend to create a null "trough" down the center of the room. I think it would be better t go with just one sub in the middle, or if you really have to have both of them, then I'd put them right next to each other in the middle of the front corner. They should also be on the floor, not part way up the wall.

does this need to be calculated based on room dimensions or something? -The soffits will be trapped prior to the front wall being finished out. I think mayube I dont quite understand your question...should they not be sealed?? I don't quite know what you mean. -Point noted on the live room. -The clouds are angled just can't see it very well in the rendering. The entire ceiling is slopes downward from front to back. Glenn what do you think about the rear wall...I really feel I need some sort of deflector on the rear wall not just absorbtion???

oops... sorry Stuart. I didn't realize you said "front corner" for placement of the sub. Well I did some research and I guess we are going to have to measure the room and see where the best placement is for the subs. Might turn out that I won't need them once the mains are in. Also wondering if having them placed a bit higher is a bad move or will it make that much of a difference...guess I will have to go with the suggested level. Anyway, thanks for the input. Moving forward this week to hopefully begin construction.

one option is to leave the subs outside of the soffit so you can move them around until you find the right spot. on the back wall - consider adding some slats etc to preserve some of the HF energy without interfering. this could be diffusers, widely spaced slats, angled slat resonators, etc.

Haaa that's funny we just said the same thing today, thank you sir for the confirmation. I am going to measure the room with the free REW software to find the best placement for the subs. Yeah on the rear wall we will have to have some slat resonators or something. I think today we decided to totally re-configure the entire design again. So now the tracking room will be in front of us and we can really trap the rear walls and have sufficient treatment at the first point of reflections. I will post once we have a new design.