The problem I'm talking about is not reflection of the lows back to the mix position, but reflection of the mids and highs back to the mix position. It seems like isolation isn't important to you at all, so you can do as Glenn suggested for the lows, and trap them above a light-weight ceiling. Not a problem. But that same ceiling will reflect mids and highs, and if it is angled as you say, then some of those will come straight back at your mix position. Maybe a cloud would help there. - Stuart -I guess what i don't get then is why cannot a lightweight false ceiling be built, if we are not deflecting lows does it matter if it isn't massive, the lows escape into the cavity in the peak where they are trapped. No?
Exterior wall concept
Originally posted at johnlsayers.com, topic 15096.
My thoughts were -That the live room is isolated from the CR by a MAM double wall, (then it retains its room within a room concept). -Floors are separate 4" insulated concrete slabs with 2' haunches as per RG's book at the wall assembly's. -The ceiling would be separated, hangers/hatbar/2 layers 5/8" DW with GG as we talked about already to stop the flanking path from the live room to the CR ceiling. So the isolation from the live room to the CR is covered, unless i am missing something. As for isolation to/from the outside in the CR i think i will just go with the same assembly as the ceiling, down the walls on the outer wall, to the equipt room and to the kitchen. Then work with treatment on top of that. It seems like a good in between to cover the occasional Cessna that may fly over or storm, along with the lower level sound produced in mixing. Am i on track mostly? Pic for quick referencecorrect, using a lightweight ceiling can help by letting the LF escape into other spaces where it can be trapped or simply release. one key point is to make sure this approach is used for both the CR and live room is to separate those spaces somewhat to avoid bypassing your other isolation - this includes considering if you allow it to escape outside...
Doesn't it only need to be angled as much or in which ever way(s) or as little as the design style of the CR says it has to be in order to create the proper re/deflections?. If it is an RFZ then we just build the ceiling to suit. I'm pretty uneducated about that stuff as of yet.The problem I'm talking about is not reflection of the lows back to the mix position, but reflection of the mids and highs back to the mix position. It seems like isolation isn't important to you at all, so you can do as Glenn suggested for the lows, and trap them above a light-weight ceiling. Not a problem. But that same ceiling will reflect mids and highs, and if it is angled as you say, then some of those will come straight back at your mix position. Maybe a cloud would help there. - Stuart -I guess what i don't get then is why cannot a lightweight false ceiling be built, if we are not deflecting lows does it matter if it isn't massive, the lows escape into the cavity in the peak where they are trapped. No?
As I said before, if it is an RFZ then the easiest way to do it is to start with the ceiling a bit lower at the front of the room (over the speakers) and angle it upwards at least 12° towards the rear. If you really do want it peaked down the center line, then you could probably do that too, but you'd have to come up with your own ray-tracing to figure out how to do that, or treat it heavily with absorption at all potential first reflection points. - Stuart -If it is an RFZ then we just build the ceiling to suit. I'm pretty uneducated about that stuff as of yet.
Well, see that is a barb. If that doesn't translate well, it means a poke...kind of what he was accused of. Fitz is a valued contributor and has mad skills in designing, and he has been here, I think longer than John? :) Man gave me some things to think about, through the years. But there are many other places that people give opinions, educated or otherwise, on the web. I have been blacklisted/banned from one of those myself :) That "walking on water" could have came from anyone pointed in any direction after having been around their posts/character for 5 or 8 years :) So back to the regularly scheduled program....Maybe post before the liqueur, please consider what is being discussed and then post regarding that topic.
dude I smiley-ed 3 times...I am getting better at emoticons :(
:yahoo:I am getting better at emoticons
Guys/gals, Allow me be clear on a couple points if you will: - I would like very much for this thread to remain as lean as possible, and by lean i mean strictly about the topic at hand which is the design of this studio. I have a couple reasons for this a) if someone were to jump into this discussion with some ideas or opinions it would be easiest for them to go back and research a bit as to what has been said so far if the thread was free of non related discussion.(such as above) b) I am donating $ and will continue to do so to this forum as long as i can have a mature group of people involved in this discussion and it remains free of a bunch of personal nonsense. Believe it or not i couldn't care less, i really couldn't, not a tiny bit less, no more than none, that's how much i care about people's personal differences. Work it out elsewhere please. I can judge people for myself. We all have our faults and quirks. I am no exception, but This thread is about the design of a studio. I don't care if you are running from the law in 30 countries if you drop by and offer a constructive thought on how to calculate the solution to a troubling standing wave. Good natured Humour is great, I'm all for it if it is mostly contained in constructive posts, again please keep the post count down, as we have a long way to go on this and we are already 11 pages. Thank youWell, see that is a barb. If that doesn't translate well, it means a poke...kind of what he was accused of. Fitz is a valued contributor and has mad skills in designing, and he has been here, I think longer than John? :) Man gave me some things to think about, through the years. But there are many other places that people give opinions, educated or otherwise, on the web. I have been blacklisted/banned from one of those myself :) That "walking on water" could have came from anyone pointed in any direction after having been around their posts/character for 5 or 8 years :) So back to the regularly scheduled program....Maybe post before the liqueur, please consider what is being discussed and then post regarding that topic.
Stuart, are you clear on the state of this building? Do you understand that the shell is built and what the shape of the shell is? If so, why would it be difficult to build the inner CR ceiling to suit the rfz concept exactly? I am not pushing for the peaked roof in the CR in any way.As I said before, if it is an RFZ then the easiest way to do it is to start with the ceiling a bit lower at the front of the room (over the speakers) and angle it upwards at least 12° towards the rear. If you really do want it peaked down the center line, then you could probably do that too, but you'd have to come up with your own ray-tracing to figure out how to do that, or treat it heavily with absorption at all potential first reflection points. - Stuart -If it is an RFZ then we just build the ceiling to suit. I'm pretty uneducated about that stuff as of yet.
Sorry to be slow, but his is not clear to me, in fact your posts have totally confused me. On one post you suggest an angled ceiling and on the other you say it will reflect mids/highs back to me. Why do you keep telling me i need an angled ceiling when i keep telling you i want to build and angled ceiling? I feel like we do not have a clear understanding of intentions here. I would like to use the RFZ principle. I would like to create a lightweight ceiling built to suit above the RFZ(angled, flat whatever is required) and i would like to put bass trapping in the space above the lightweight ceiling. Questions: - Is this a reasonable, efficient, effective approach? - How do we begin to work with room dimensions, given the peak of outer ceiling of the CR?-As I said before, if it is an RFZ then the easiest way to do it is to start with the ceiling a bit lower at the front of the room (over the speakers) and angle it upwards at least 12° towards the rear. ???? If you really do want it peaked down the center line, then you could probably do that too, but you'd have to come up with your own ray-tracing to figure out how to do that, or treat it heavily with absorption at all potential first reflection points. -The problem I'm talking about is not reflection of the lows back to the mix position, but reflection of the mids and highs back to the mix position. It seems like isolation isn't important to you at all, so you can do as Glenn suggested for the lows, and trap them above a light-weight ceiling. Not a problem. But that same ceiling will reflect mids and highs, and if it is angled as you say, then some of those will come straight back at your mix position.?????? Maybe a cloud would help there. ..... About your ceiling angle: Yes, it can be angled to help direct reflections away from your mix position, but you can't really do that with a peak down the center-line. The normal way to do that is to start with the ceiling lower down at the front of the room, and angle it up at about 12° or more, so it is higher at the rear of the room.
Sorry to be slow, but his is not clear to me, in fact your posts have totally confused me. On one post you suggest an angled ceiling and on the other you say it will reflect mids/highs back to me. Why do you keep telling me i need an angled ceiling when i keep telling you i want to build and angled ceiling?"
The issue, seaweed, is based in several things. One is that Stuart mentioned two different ceiling styles, the other is the lack of construction education that far to many have and still think they can do something that requires 4 or 5 different trades of high professional level, but we see it all the time that people will attempt a DIY recording environment and do not even own a hammer:)
The first ceiling mentioned is a flat ceiling with a 12 degree lift:
The second is a vaulted ridge line:
BUT, he and you may be talking about something so foreign to me that I can not diagram it based on my mere 30+ years of commercial and residential construction:)
But I doubt it ;)
Exactly like Brien said: You are talking about a totally DIFFERENT kind of ceiling angling. As I said several times already, if you start with a simple ceiling that runs flat ACROSS the room, but is lower at the FRONT of the room and higher at the BACK of the room, angled up at about 12° or more, then you have the basis for an RFZ ceiling that will help to reflect sound AWAY from the mix position. But that is not what you are talking about. You are talking about a PEAKED ceiling, that starts low on EACH SIDE of the room, and rises to a peak that runs down the CENTER LINE of the room. That ceiling too will reflect sound, but chances are that it will reflect it right AT the mix position, instead of AWAY from the mix position. Just think about the angles, and you should see why this happens. Like I also said, with some careful design and lots of ray tracing, you MIGHT be able to design such a ceiling so that it reflects things away from the mix position, but it won't be easy.On one post you suggest an angled ceiling and on the other you say it will reflect mids/highs back to me. Why do you keep telling me i need an angled ceiling when i keep telling you i want to build and angled ceiling?
... which implies that you don't need much isolation for your room: in other words, you don't have anything noisy in the building or nearby that might bother you in your room, such as radios, TVs, telephones, people, dogs, cars, roads, airports, wind, rain, thunder and other noisy things? And you also don't have any other people around you that you might bother with the sound escaping through your light weight ceiling? Is that correct?I would like to create a lightweight ceiling ...
Once again, you CAN do that, but why not just go with a more conventional design, that would be easier (and cheaper) to build? Or if you really like the idea of bass traps in the ceiling, then raise the real inner-leaf ceiling high enough to allow for abundant hangers or whatever, and hide them behind a cloth ceiling? That wouldn't really be an RFZ ceiling, but it would still work.and i would like to put bass trapping in the space above the lightweight ceiling.
If you are talking about room ratios, then you can't use the normal tools for predicting room behavior if you have a strongly peaked ceiling, since those tools only work accurately for rectangular rooms (with six walls, not seven). So if your inner-leaf room is not rectangular, then you can't predict its modal response easily, using the common on-line calculators. On the other hand, if you do build a rectangular room inside that peaked outer shell, then you can use those tools, and you can predict behavior. - Stuart -How do we begin to work with room dimensions, given the peak of outer ceiling of the CR
Stuart, I need you to confirm that you understand that this building is built. It is a shell with an angled ceiling. It's already there, the angled ceiling.
Tell me you know that and then i can get back on the road to trying understanding what you are trying to say to me.
Because i just do not understand why you keep telling me the difference between the 2, i think i get it, i think i got it the first time but we are still there.
This is the shell of the building below.
I plan to put the mass on the ceiling at the peak in the CR section and deal with reflections with the other lighter lower ceiling, the space in between will be used as trapping. No i don't need major isolation for the CR to the outside.
What am i missing?
so... for proper symmetry in the CR - you need to mask the effect of the upper exterior ceiling by making another ceiling for the CR sit squarely across the CR walls -- angled front to back (low to high), or peaked front to back (i think i drew something like that a while back), or flat up high as possible and with a false ceiling and hangers etc. otherwise a peak which is off-center over your listening position will be annoying at best.
On a different note for a second, i have been looking at how to seal this outer wall properly. The trusses come down and rest on the upper plate 2x6 of the outer wall then extend out a couple feet to the outside to create the overhang, there are air(insulation) spaces between the trusses. In order to seal the outer mass layer and create an air tight 'space' i have to deal with the space above the 2x6 plate where the insulation is the only substance all the way to the inner wall assembly in order to stop sound from just going out into the soffit. My question is: where do i stop and seal the drywall near the inner wall assembly? Please feel free to have a giggle at my pencilship, i could always play the guitar but never the pencil.layout the rooms carefully and have the ceiling drywall conform to the room layout so you have gaps where you need it to avoid coupling the rooms. the walls, assuming back-to-back could be braced using isolation brackets and anchored, the upper parts could be anchored using isolation brackets to the trusses to add additional stability without being coupled.then your drywall layering and backer rod/caulking would be per normal to achieve the proper seals with limited or no hard contact between the walls and ceiling drywall.
I'm feeling like a real blockhead here, i feel like i keep saying i want to do exactly what you guys keep telling me i need to do and then you tell me again that i need to do it because...... so and so.
I must be missing some key point.
"so... for proper symmetry in the CR - you need to mask the effect of the upper exterior ceiling by making another ceiling for the CR sit squarely across the CR walls"
Got it, i want to do that.
What construction is recommended for this ceiling if i do not need LF isolation?
"angled front to back (low to high), or peaked front to back (i think i drew something like that a while back), or flat up high as possible and with a false ceiling and hangers etc. otherwise a peak which is off-center over your listening position will be annoying at best"
Right, got that, i want to do that. It is obvious to me that it needs to be symmetrical and that the peak would be trouble causing.
I do not want a peaked ceiling in my control room.
Backing up a bit, What is the effect exactly that we need to mask from the peaked ceiling?
I ask this because it seems to me it must be exclusively LF build up, because we are all agreed that the direct reflections of the peak will be problematic.
Is this it? Given i have said several times that i want to make an angled ceiling in accordance with the RFZ requirements? If i do that, what residual negative effects are we left with from the peak if i use a light weight ceiling?
Does the CR HAVE to be sealed with major isolation across the full frequency range in order to calculate the modes etc.
Cannot the ceiling be lightweight and let the lows escape into the space above it(the peak, and be trapped) or escape to the outside?)
This building is ALL studio, there will be no other activities going on in it while recording is happening.
Yes, I do realize that your outer shell is already built. That isn't the issue. The issue is what you are going to do with your INNER leaf ceiling, which might or might not follow the same lines as the outer leaf.
Once again, that comes back to a simple question: How much isolation do you need? In this case, we are talking about isolation between your CR, LR and any other rooms in the building. Many people (me included) find it hard to track well if they can hear the instrument in the CR monitors AND ALSO hear it coming through the walls/floor/ceiling. If that doesn't bother you at all, and you find it simple to set up mics on a drum kit when you can hear the drum sound coming from two places at once, at different levels, different EQ, different timing, etc., then you don't need to isolate your CR. Another scenario: If you don't mind bleed from the CR speakers getting back into your mics in your vocal booth, then you don't need to isolate your CR. If you don't mind the sound of toilets flushing, phones ringing and people talking in other parts of the building getting into your LR and booth mics, then you don't need to isolate. If you don't mind the sound of wind, rain, thunder and passing aircraft getting into your mics while you are recording, then you don't need isolation. On the other hand, if any of those issues of bleeding between rooms might be objectionable to you, or to the people who use your studio, then you DO need isolation. For most sound engineers that I know, these are all critical issues. Bleed between rooms and unwanted sound getting into mics is a show-stopper. But maybe it's not important to you, and to the type of music you are going to make in that studio. It's a personal issue. Which comes back to the question: how much isolation do you need? If your rooms are not isolated at all and you use the space above for heavy bass trapping, then you will have bleed issues. If you isolate the rooms well enough to kill all bleeding (eg. so you cannot hear the drums through the walls in the CR), then the bass trapping needs to go INSIDE the room, not outside of it. So what I'd suggest that you do is first to rethink your isolation strategy, put real numbers (in terms of decibels of transmission loss) on your isolation needs, set those numbers as goals for your build, then look at the type of structure you will need to obtain that amount of isolation. Only then can you decide if you can leave your CR un-isolated, and use the space around it for bass trapping. Then, if it does turn out that you need isolation in order to have a viable studio, then you will have to plan on how to shape your rooms so that you can get the amount of bass trapping that you need, dictated by the volume and dimensions and design of the room. Then, and only then, should you be worrying about what angles to place your ceiling at. If you start out by setting our ceiling angle as a design goal, I can guarantee that you will run into major issues later with how to keep that while still accounting for the necessary isolation and treatment. Trying to define your studio build based on the ceiling angle is like trying to define what car to buy based purely on a preference for tire size.Does the CR HAVE to be sealed with major isolation across the full frequency range in order to calculate the modes etc. Cannot the ceiling be lightweight and let the lows escape into the space above it(the peak, and be trapped) or escape to the outside?)
No phones ringing? No water running? No people talking? Nobody walking around? Nobody accidentally dropping things in the office / bathroom? No toilets flushing? No microwave running? No fridge? No air conditioning system? No computers? No printers? No cars leaving / arriving? No wind? No rain? No thunder? No planes flying past? Are you absolutely sure you can control all of those, and about a million other things? :) - Stuart -This building is ALL studio, there will be no other activities going on in it while recording is happening.
Thanks for taking the time to write that. My thoughts on the separation from the main room to the CR, kitchen and storage rooms were that the whole wall, 40 feet across would be floor to the ceiling(top of peak) and be a MAM wall. From there the walls between the storage/kitchen and CR would be lighter grade as the noise is less from those to each other. So i guess this is why i thought the space above the CR could be used for LF absorbing because it is blocked by the MAM wall of the live room. that whole third or so of the building is. And between the CR and kitchen and CR and storage would be walls floor to ceiling as well, sealed etc. So a bit of the LF could escape through that wall to/from the kitchen or storage but it wouldn't be a big deal. It makes sense to me to use the remaining space above the CR for LF trapping as it is just sitting there wasted otherwise, thus the light ceiling idea, let it go up there, trap it, done. Plus a savings on $ on the light weight CR ceiling. As i mentioned before the whole peak ceiling would have the isolation of the clips/track/dw/gg/dw system so that acts as the isolation from outside and handles the fire code stuff. Does this help us connect on our non connection?Yes, I do realize that your outer shell is already built. That isn't the issue. The issue is what you are going to do with your INNER leaf ceiling, which might or might not follow the same lines as the outer leaf.Once again, that comes back to a simple question: How much isolation do you need? In this case, we are talking about isolation between your CR, LR and any other rooms in the building. Many people (me included) find it hard to track well if they can hear the instrument in the CR monitors AND ALSO hear it coming through the walls/floor/ceiling. If that doesn't bother you at all, and you find it simple to set up mics on a drum kit when you can hear the drum sound coming from two places at once, at different levels, different EQ, different timing, etc., then you don't need to isolate your CR. Another scenario: If you don't mind bleed from the CR speakers getting back into your mics in your vocal booth, then you don't need to isolate your CR. If you don't mind the sound of toilets flushing, phones ringing and people talking in other parts of the building getting into your LR and booth mics, then you don't need to isolate. If you don't mind the sound of wind, rain, thunder and passing aircraft getting into your mics while you are recording, then you don't need isolation. On the other hand, if any of those issues of bleeding between rooms might be objectionable to you, or to the people who use your studio, then you DO need isolation. For most sound engineers that I know, these are all critical issues. Bleed between rooms and unwanted sound getting into mics is a show-stopper. But maybe it's not important to you, and to the type of music you are going to make in that studio. It's a personal issue. Which comes back to the question: how much isolation do you need? If your rooms are not isolated at all and you use the space above for heavy bass trapping, then you will have bleed issues. If you isolate the rooms well enough to kill all bleeding (eg. so you cannot hear the drums through the walls in the CR), then the bass trapping needs to go INSIDE the room, not outside of it. So what I'd suggest that you do is first to rethink your isolation strategy, put real numbers (in terms of decibels of transmission loss) on your isolation needs, set those numbers as goals for your build, then look at the type of structure you will need to obtain that amount of isolation. Only then can you decide if you can leave your CR un-isolated, and use the space around it for bass trapping. Then, if it does turn out that you need isolation in order to have a viable studio, then you will have to plan on how to shape your rooms so that you can get the amount of bass trapping that you need, dictated by the volume and dimensions and design of the room. Then, and only then, should you be worrying about what angles to place your ceiling at. If you start out by setting our ceiling angle as a design goal, I can guarantee that you will run into major issues later with how to keep that while still accounting for the necessary isolation and treatment. Trying to define your studio build based on the ceiling angle is like trying to define what car to buy based purely on a preference for tire size.Does the CR HAVE to be sealed with major isolation across the full frequency range in order to calculate the modes etc. Cannot the ceiling be lightweight and let the lows escape into the space above it(the peak, and be trapped) or escape to the outside?)No phones ringing? No water running? No people talking? Nobody walking around? Nobody accidentally dropping things in the office / bathroom? No toilets flushing? No microwave running? No fridge? No air conditioning system? No computers? No printers? No cars leaving / arriving? No wind? No rain? No thunder? No planes flying past? Are you absolutely sure you can control all of those, and about a million other things? :) - Stuart -This building is ALL studio, there will be no other activities going on in it while recording is happening.
Awaiting Stuart...... does what i wrote make sense of the previous posts now?
I think you could use that space for trapping. One consideration, AC ducting. That space could also house the large AC ducts into the various rooms, plus baffle boxes, etc.
I met with my air handling guy the other day and we discussed that idea.
Above the bathroom looks like a great spot for the unit to live. It can draw from the opposite side of the building as the wood chimney(10X10 room) and can be contained in it's own little sealed room, far from the live room. The space above the CR would certainly be helpful for running some duct.
I'm looking at strictly air exchange. Again i am using in-floor heat in the slab thoughout.
My rooms are all big enough, and having lived and worked here for a decade, i just don't think cooling is required. Fresh air is though.
The climate here is pretty/very dry.
So i might look at humidity control in the bright room if i get a piano in there.
One thing we discussed was keeping the noise down by using the smallest unit we could for air exchange.
The one we talked about maxes at 150cfm and has 3 speeds. Through the use of dampers it could be used efficiently depending on how the studio is being used. It's important that i can idle and just treat me in the CR by myself as that is the case a good potion of the time
We worked out each room and it's potential # of occupants at 10 cfm per person.
From what i read in RG's book we should be using 15cfm, but the Air guy thinks 10 is the number so i let him work it out like that.
But after we talked and calculated it all looked a bit conservative so i think we might notch the machine up one size and go for the 15 cfm.
As i can easily deal with the walls around the room to the unit how ever is appropriate for it's noise.
How am i doing on that?
Thoughts on 10-15 cfm per person?
air volume versus air velocity: you want enough air volume to change the air in your rooms roughly 6-8 times per hour. so if you have a 1000ft3 room you want 6000ft3/hour or 100ft3/minute (cfm). use zoned approach to controlling each room keeping in mid pressure balancing the system. the air velocity should be under 300fps and better yet 100fps or even lower if possible. you also want your diffusers and return covers to minimize noise from air moving through them and consider air filters on the returns to keep ducts clean (as well as the unit "whole house" filter(s) which are required regardless).
Is the air exchange of 6-8 times per hour based on # of people or the type of activity or ?. Just so i understand this approach as it seems different to calculating it per person.air volume versus air velocity: you want enough air volume to change the air in your rooms roughly 6-8 times per hour. so if you have a 1000ft3 room you want 6000ft3/hour or 100ft3/minute (cfm). use zoned approach to controlling each room keeping in mid pressure balancing the system. the air velocity should be under 300fps and better yet 100fps or even lower if possible. you also want your diffusers and return covers to minimize noise from air moving through them and consider air filters on the returns to keep ducts clean (as well as the unit "whole house" filter(s) which are required regardless).
There are two schools of thought. One is providing sufficient air to maintain good oxygen. This is the "per person" method. The other is providing fart, sweat and other obnoxious odour removal. This is the "excahnge rate" model. AndreIs the air exchange of 6-8 times per hour based on # of people or the type of activity or ?. Just so i understand this approach as it seems different to calculating it per person.
but its the human qualities we share and endure that make us what we are... :twisted: it's a "general rule", the actual exchange rate should take into account the # of bodies and working levels to estimate the CO2 levels, and then the latent and heat loads to be considered for cooling/conditioning.The other is providing fart, sweat and other obnoxious odour removal. This is the "exchange rate" model.