Sketchup for my new control room

I'm slowly becoming depressed...

You shouldn't be! It's a narrow room, for sure, but it is what it is, and I think it can be made usable, albeit with some limitations. As long as you can live with those, then it will work.

I've got to work with what I've got I'm afraid. Its not ideal but it is surely workable??

Exactly! If that's what you've got to work with, than that's what you've got, and we just have to figure out the best that can be done with it! It ain't the end of the world, and successful studios have been built in spaces similar to yours, WITH soffit mounted speakers AND a door into the LR, behind the console, between the soffits. Despite what you might have heard to the contrary, that is a valid configuration, and it does work.

my desk / console setup is not massive so there should be some room either side to get past.

Plus, like I said before, speaker geometry can be nudged, and room ratios can be chosen, to maximize that space, and give you enough room to get through that door. Once again, it wont be optimal acoustically, but there is no reason why it won't work reasonably well. Question: How narrow can that CR-to-LR door be? What is the absolute minimum width that you could live with? Don't forget that the door has to open towards the console, so the width of the door will dictate the position of the console. If you can live with a narrow door, that gives you two advantages: 1) The console can be a bit closer to the front wall, improving your geometry, and 2) your soffit panels can be bigger, giving you tighter bass and better imaging. Also, how big is your desk surface going to be? Or rather, what are the absolute minimum dimensions of the desk that you can live with? Also, Does your console have any cables that need to exit straight out the rear, or do they all exit up vertically from the top? If anything has to exit out the rear, then you might need to buy 90° plugs for all of those, to reduce the space needed for the cables to exit. A bit extra cost, but it can save quite a few inches like that. So don't get depressed: I think your space is very narrow, but still usable. SOMETHING can be done in there, for sure. The only question is if that "something" is going to be what you need or not. Post the answers to the above questions, and I'll see if I can figure something out. It might not be possible to keep the splayed walls, but I reckon you can keep the soffits, since others have done that successfully in similar sized spaces: But I would still go with inner-leaf side walls, built inside-out (even though you say you don't need much isolation to the sides) for three reasons: 1) Isolation: Even though you say you don't need isolation to the sides, you DO need it to the LR. You'll have a 2-leaf MSM wall to that room, which is great, but if you don't also have a 2-leaf ceiling and 2-leaf sidewalls around the CR, then your 2-leaf divider wall won't be able to do it's job, as sound will "flank" around it. And you also won't have any way of holding up that wall! So you also need the side walls structurally. But build "inside-out"... 2) Space: Built inside-out, they don't take up much space in the room at all. If you use a 4" air gap, then I can show you how to build them so that you only loose about 12 cm of depth (acoustically) on each wall, or 24 cm width. I think you can afford that! Especially considering the benefits. And if you take it down to a 3" air gap, then you only need to lose 9 cm on each side, total of 18 cm. 3) Acoustic treatment: Building inside-out leaves the stud space facing the room, and you can use ALL of that for acoustic treatment! Free space! If you build the walls "normally", then not only do you lose extra room width and depth, but you then have to build your acoustic treatment ON TOP of those walls, which takes up even more room width... So that would be my recommendation: Build those sidewalls that you were no considering before because they were taking up too much space, but build them inside out. And don't get depressed: it can be done. It has been done before. So you can do it too. - Stuart -

That's the DOOR that I mentioned you had left out. The one from the CR to the LR.

Apparently, you knew something that I hadn't picked up on. The ONLY thing I had to go by at that moment was HIS drawing, which showed that area as a SOLID WALL. :roll: In fact, the drawing didn't reflect the whole room at all. Also, that wall isn't even BUILT, yet I was somehow supposed to know that? Plus given the fact he wants not only SPLAYED walls, which make this wall even narrower, he also wants soffits, which if you adhere to the "2x baffle" definition, makes this opening for a door...well, lets see...how skinny are you.

Well, gee, that kind of is the normal way to build an MSM wall! Two leaves of mass, with an air gap between, on two separate stud frames.

Well, gee, what part of "solid wall" in his first drawing didn't you understand? He didn't bother to tell anyone this wasn't the actual far wall in the REAL room. In reality, that wall in the FIRST file isn't even built yet. I asked this question ASSUMING the LIVE room was on the other side of the door...that HE DREW. :roll: This is what I get when I don't know everything about a project and try to IMPROVE the Sketchup representation. BTW, I fully understand MSM construction. EXCEPT when it LOOKS LIKE a double wall in FRONT of what I assumed was a SOLID WALL. :roll:

Quote: You mean to tell me that you are planning a door...in front of your console, between soffits???????? And there is a problem with that? Is there a good acoustical reason why doors should not be placed in front of consoles and between soffits?

Yea, if you can't get through it!!! geeezus This is ASSUMING that you ADHERE to the 2x principle, and by the time you REALLY add the drywall, jambs etc....the dimension shown is even smaller. :roll: If you make the soffits narrower...then whats the point?...same with the splayed walls. Personally, considering the fact that most acousticians recognize that in small rooms, the reasons for splaying walls is hardly significant enough to loose the space, as flutter echo can be overcome via sidewall absorbers, which you will have to use anyway to reduce early reflections, which NOW, adds even more thickness to the splayed walls, further reducing the area for a console. But thats not my call. Only the owner can make those determinations. I only try to help with the visualization so you can evaluate the realities in 3d, which I did. Apparently though, no one gets it.

Sure, in this case it doesn't leave much size for the soffits,

Ha! no, in this case, unless you ignor the POINT of soffit baffles, you are reducing the DOOR width. Somehow, I get the feeling that your opinion is .."to hell with the principles..you can fudge this and that and STILL get the results that the principles work on. I disagree. I think you could get FAR better results by leaving the room rectangular, using speaker stands, and treating the room as such. But who am I?? :roll: I'll tell you. I'm a cheapskate who hates spending money on stuff that is based on VIEWPOINT OPINION, for arbitrary reasons, and you couldn't PROVE had an impact on the final result if your life depended on it.

Well, gee, how about changing the geometry of the mix position and speakers? As was discussed earlier in the thread. I guess you missed that part....

yea, how bout it. If you widen the equalateral triange ANGLE, you make more distance between the engineering position and the monitors. However, you also reduce the angle of soffits which now approach a SPECULAR FLAT WALL . Whats the point of soffits then, other than having an infinate baffle. And btw, while were at it, it might interest you to know something. First off, I built soffits for my control room, which was NO EASY TASK nor cheap to impliment. And the reason was simple. THEY WERE HIGHLY RECOMMENDED by this very bbs's resident speaker "guru" and physicist..Mrr. barefoot himself, whom I believed just like I believed Alton Everest and his "advocation" of QRD's for "small room diffusion".....only to find out later, at least in the case of "ORD's", that in the words of this bbs's OWNER, Mr. John Sayers........(amongst others)...that QRDS..."don't work"!!! And THEN, while posting a reply in regards to soffits on another bbs, I had the pleasure of reading Mr barefoot totally repudiate his prior stance on "soffits". Don't believe me?..read it here...... :roll: Here is what he wrote in 2003 http://homerecording.com/bbs/showthread ... eestanding and then his reversal based on "new insights" :roll: http://homerecording.com/bbs/showthread ... ing&page=2 Look, I don't mean to come here and display my opinions of studio design practice. However, I think its fair to let other people know that there are many things in the "studio design" universe that are completlely "opinion" oriented, and if someone happens to SELL products that they advocate as a professional "acoustical science" practitioner(ie..QRD's/RPG as an example), the only thing that comes to mind is....Caveat Emptor! Soffit mounting is no exception. :roll: Niether is splayed walls.

The normal way is to duct them all through conduit, which could be chased into the floor,

You mean like this...these are the LEGS to my console, which die into floor chases. You assume I know little. :roll:

Huh? Use the short axis? As in: "have the speakers firing across the room, instead of down it"? Is that what you mean?

I do. If it solves the skinny door problem. Whats the difference? You want to change the speaker angle and the baffle width. Besides, close proximity rear walls are common to home studios around the world. He wouldn't be the first to deal with it.

If so, I assume that was meant to be some kind of sick joke. Not funny.

I suggest you tell John that HIS jokes aren't funny either. :roll:

cadesignr ?? looks like theres a door in your control room?? And it looks like a door in his???

looks like theres a door in your control room??

You're absolutely correct. However, its a sliding glass door that hasn't been removed yet. It only goes out to a deck. Besides, even if it weren't removed I have four feet from the back of the console to the door, and almost 54" clear space at the midpoint between soffits. Nice try though. Once removed, the front wall will look like this.

Also, that wall isn't even BUILT, yet I was somehow supposed to know that?

Well, gee, I guess I must have read his threads, and kept track of what he was doing. I guess that's why. Maybe! :)

which if you adhere to the "2x baffle" definition,

Definition? Didn't look like a definition to me. More like a suggestion that Ro made. The normal recommendation for soffit panels is 48" all around (which of course gives you good control down to about 20 Hz. obviously), or as big as you can make it within the limitations of the room. You have to live with what you've got. Your soffits don't seem to be 48¨wide.... Nor do they seem to be "2x baffle" wide.... Hmmm... (Maybe it's just the camera angle....)

Well, gee, what part of "solid wall" in his first drawing didn't you understand? He didn't bother to tell anyone this wasn't the actual far wall in the REAL room.

Ummmm, actually, he did. He made it clear that the wall isn't there yet, especially in the photos, and he also made it clear that this is an MSM divider wall, not a solid wall. There were several posts discussing this exact point. I guess you missed those too.

BTW, I fully understand MSM construction. EXCEPT when it LOOKS LIKE a double wall in FRONT of what I assumed was a SOLID WALL.

Strange, but it looks pretty clear to me. Especially given the extensive discussion in his threads on how that wall is going to be built... Maybe you missed that.

Yea, if you can't get through it!!!

So you don't actually have a good acoustical reason for your comment that doors should not be placed between soffits? I didn't think so...

This is ASSUMING that you ADHERE to the 2x principle,

And what "2x principle" would that be? :)

Personally, considering the fact that most acousticians recognize that in small rooms, the reasons for splaying walls is hardly significant enough to loose the space, as flutter echo can be overcome via sidewall absorbers, which you will have to use anyway to reduce early reflections, which NOW, adds even more thickness to the splayed walls,

Unless, of course, you build inside-out walls...

unless you ignor the POINT of soffit baffles,

Which you think is...?

I get the feeling that your opinion is .."to hell with the principles..you can fudge this and that and STILL get the results that the principles work on.

Ummmmmmm.... no, my opinion is that you have to live with what you've got, and use the science of acoustics to make the best you possibly can of the room you are working with. You have a better idea than that, maybe?

I'm a cheapskate who hates spending money on stuff that is based on VIEWPOINT OPINION, for arbitrary reasons, and you couldn't PROVE had an impact on the final result if your life depended on it.

So you don't think I could prove that splayed walls and speaker soffits have an impact on final results: hehehe! :!: :lol: hoooboy!

If you widen the equalateral triange ANGLE, you make more distance between the engineering position and the monitors.

Well, gee, that kind of is what Ian was wanting to do, now isn't it? Or did you miss that part too? You do seem to be missing an awful lot here....

However, you also reduce the angle of soffits which now approach a SPECULAR FLAT WALL .

And that would be detrimental in what way? What is the minimum angle at which it is possible to set a soffit panel, and why? Why is not good to have flat wall soffits, and what happens if you do, acoustically?

Whats the point of soffits then, other than having an infinate baffle

Well, gee, putting a massive, rigid and dense infinite baffle around the speaker kind of is the point of a soffit, isn't it? Yet curiously enough, your design (although it looks really snazzy) does not accomplish that.... Hmmm.... And of course, it won't work for Ian's speakers anyway.

First off, I built soffits for my control room, which was NO EASY TASK nor cheap to impliment.

Well, gee, nobody says otherwise, as far as I know! Doing soffits right ain't easy!

in the words of this bbs's OWNER, Mr. John Sayers........(amongst others)...that QRDS..."don't work"!!!

Hmmm.... I can't say that I recall John saying that. I do seem to recall him saying that he doesn't recommend them for small rooms, but I don't believe he has said flat-out that they "don't work".

Look, I don't mean to come here and display my opinions of studio design practice.

Yet you seem to be doing exactly that, and doing a real fine job of it! :)

However, I think its fair to let other people know that there are many things in the "studio design" universe that are completlely "opinion" oriented,

Sure there are! But you'll find that most people on this forum tend to prefer basing their designs on solid science, not on opinions. Which might be why so many successful studios get built here. And of course the science behind soffit mounting and splayed walls is not a matter of opinion anyway. If you were to talk about hangers like that, then I'd have to agree with you, since there is practically no science on those at all. But soffits and splayed walls have plenty of solid science to recommend them.

Soffit mounting is no exception. :roll: Niether is splayed walls.

Except, of course, that both of those are based on sound scientific principles, and work well when implemented correctly. Which does not imply that they constitute the ONLY way to build a studio, but it does mean that they do work as advertised when designed and built according to the underlying science.

I do. If it solves the skinny door problem. Whats the difference?

You gotta be kidding, right? You really would fire the speakers across the short dimension of such a long thin room, just in order to not make a door and a pair of soffits a bit narrower than normal? :shock: Wow!! What can I say? :!:

You want to change the speaker angle and the baffle width.

Yup. But based on the acoustic principles behind doing that, of course, and following the science, within the limitations imposed by the room itself. Balancing the science against the room to try to get the science to work as well as possible, given the limitations imposed by the room. Not by just guessing: Such as for example guessing that it could be better to fire the speakers across a very long, narrow room than to fire them down it, just in order order to have a wide door...

I suggest you tell John that HIS jokes aren't funny either.

I'd hardly call any of John's designs a joke! Beside which, you seem to have measured the dimensions wrong: the acoustic depth of that room is 347.0 cm, not 323.2. Not sure where you got that from! (The acoustic width is also not 356.3... ) Do you need some help in learning how to measure the acoustic dimensions of a room? In any event, that room hardly compares with Ian's situation: his room is nearly six meters long, by little more than two wide... Once again, John took a room with very limited space, and made the absolute best possible use of it. That means that he had to "fudge the rules" a bit in order to make it work. It ended up practically square, with the mix position practically in the center, but he did several things to the design to deal with those issue, and minimize the effects, as you can see. It also meant that the speakers have to fire along a short axis, yes, but that "short axis" is less than 10% different than the long axis. Whereas you want to fire Ian's speakers down an axis that is roughly 250% different... Did you really think that the situations are comparable? Hmmmm. In any event, John took a room with very limited space, and made the absolute best possible use of it, adjusting and nudging things to optimize as mush as possible given the limitations imposed by the room itself. And the room turned out to be very successful Which is what the rest of us are trying to do with Ian's room.

...the front wall will look like this.

those soffit panels look awfully small. There's only a couple of inches of solid flat surface around them in some places. I can't see that they'll act much like an infinite baffle, given those dimensions... They make real pretty decorations, though!

Hi, I'm going to stay out of the arguement and answer Stuarts questions.

Soundman2020 wrote:

Question: How narrow can that CR-to-LR door be? What is the absolute minimum width that you could live with?

I can live with a narrow door. If 48" is the ideal soffit width then I agree, the narrower door the better, acoustically. Maybe 26"? It may be better to let the soffit size dictate this up to a point, keeping it realistic, if you see what I mean. We can be flexible with the door size.

Soundman2020 wrote:

Don't forget that the door has to open towards the console, so the width of the door will dictate the position of the console.

This may be a point of confusion here. The door doesnt have to open in to the control room, I can put it on the live room side of the 2 leaf wall so it opens in to the live room and build a deep baffle on it on the control room size of it. Not ideal atall from the isolation point of view but we could discuss that seperately (if we start discussing it now, we'll go off on a tangent, I'll bring this up on my other post regarding the wall/ceiling construction if you are in agreement). There is obviously going to be compromise in this design and I can afford to compromise on isolation for the sake of an acoustically balanced CR. I do a lot more mixing and creating in the CR than I do live recording.

Soundman2020 wrote:

Also, how big is your desk surface going to be? Or rather, what are the absolute minimum dimensions of the desk that you can live with?

The desk I use is:- Width: 151 cm, Depth: 85 cm, Height: 73 cm. The mixing desk (console) I use sits on this desk as do my computer screens (although the screens can be moved forward away from the monitoring position to keep them out of the line of the monitors). The console is only currently a Yamaha 01v so not very big. I think I'm going to be changing this for an analogue desk but it prob wont be all that much bigger and will still fit on the desk. The desk can be positioned closer to the left hand splayed wall than the right to allow a 'corridor' past it on the right hand side by where you enter the room. I can still sit centrally.

Soundman2020 wrote:

Also, Does your console have any cables that need to exit straight out the rear, or do they all exit up vertically from the top? If anything has to exit out the rear, then you might need to buy 90° plugs for all of those, to reduce the space needed for the cables to exit. A bit extra cost, but it can save quite a few inches like that.

I think the door opening the other way (into the live room as described above) should get around this. Now then, coming on to the inside out walls...... Firstly, what size timber would these be made of? Are you talking 4"x2" or 2"x1" etc? I'm still not understanding how they would be built insuch a way that would keep them decoupled from the existing side walls....This is a topic to continue on the other post me thinks!!! I think it is sort of a 'room within a room' with all 2nd leaf walls attached to each other and to the floor but not attached to the existing walls. I still need to read a very basic explanation of this unfortunately in order for it to sink in :oops: I'm honestly in 2 minds over the side walls. Let me explain why.. Firstly, I know what you are saying is acoustically the right thing to do, please dont think I'm being dismissive of it in any way, its just that there are a few other factors I need to consider. One thing is, Around the window and on the right hand (chimney breast) wall and around the door to the house, this will be very difficult to implement and build. Secondly (and again this may be a topic for the other post), Due to the construction of the existing ceiling, I will not be able to fully decouple the inner ceiling leaf I'm going to build (once planned) from the existing leaf (flat roof). I'll take a photo later when I get home to show you what I mean. Thirdly, we are definately planning on staying in this house for the next 3 years at least. After that we may move. I've got to keep the wife happy (you know how it is :wink: ). The wife is happy for the soffits and splays to go up but would be a lot happier if we didnt fundamentally alter the width of the room (for when we come to sell it) which is why, after discussing, we decided the initial idea would be to splay from the soffits down to the existing side walls then treat the back half of the room with baffles and superchunk traps etc. It is a narrow feeling room when you are in it and could easily cross the line from being very comfortable to feeling claustrophobic. I thought baffle panels would make it feel more comfortable and could provide a good level of acoustic treatment. Also, I thought that leaving some of the existing side walls 'exposed' around the baffles would assist in keeping the room bright. I thought if it was rockwool covered in material all the way around (which is what I assume you would do with an inside out wall), it may make the room very dull as there would be little in the way of reflective surfaces. What do you think?

The other thing to bear in mind, and I've only just thought about it (been that busy thinking about the CR and structure) is that I definately wont be able to build inner leaf walls in the live room, it was never my intention to do this due to cost and size. If I'm seeing this correctly. That means that the new 2 leaf dividing wall will have to be attached to the existing outer walls in the live room which would sort of negate the benefits of decoupling it in the control room.....If I'm finally getting a clear picture of how its supposed to work....

I can live with a narrow door. If 48" is the ideal soffit width then I agree, the narrower door the better, acoustically. Maybe 26"? It may be better to let the soffit size dictate this up to a point, keeping it realistic, if you see what I mean. We can be flexible with the door size.

Great! OK, let's see what we can come up with for a good combination of door width and soffit width.

This may be a point of confusion here. The door doesnt have to open in to the control room, I can put it on the live room side

Well, actually you need TWO doors, one on each side! A door or window is always the weak link in an MSM wall, and there is no way that a single door can even come close to giving the same level of isolation as the wall itself: You need two heavy doors, back to back, one for each leaf, with an air gap between, in order to get good isolation. And at least two seals around each door.

The desk can be positioned closer to the left hand splayed wall than the right to allow a 'corridor' past it on the right hand side by where you enter the room. I can still sit centrally.

I'd try to avoid doing that, since room symmetry is very important, at least up to the mix position (your head). Behind that it's not so important, but up to there it is fundamental to have good symmetry. Even though the desk surface is not (or should not!) be in the direct path from speakers to ears, it is still there, and still changing the acoustics. So an offset desk would probably not be a good idea, but there should still be enough room to get past on one side. I figure about 40 cm. However, if you could get a slight smaller desk, that would be to your benefit. I'm not saying that you CANNOT offset the desk to one side: It can work like that. But you are going to have to make so many small acoustic "sacrifices" in order to make the room work that it makes sense to NOT make some of them if it can be avoided.

I think the door opening the other way (into the live room as described above) should get around this.

Well, not really! :) See above. There is another option for doors, but I hesitate to suggest it, since it is so hard to get it sealed right, but I'll mention it just in case you happen to know a master carpenter who could get it right: Pocket doors. In other words, sliding doors that slide into the wall itself. They don't swing into either room, so they don't take any space. But sealing them acoustically would be a nightmare.

Firstly, what size timber would these be made of? Are you talking 4"x2" or 2"x1" etc?

I'm thinking that 2x3 16OC for the side walls will probably be OK, at least for the part around the desk and front wall, and 2x4 for the rest. Your ceiling span isn't that great, and worst case you can sister studs for extra strength (although I imagine that Brien won't be too happy about that idea!).

I'm still not understanding how they would be built insuch a way that would keep them decoupled from the existing side walls...

The new inner-leaf side walls stand on the floor, a couple of inches away from the existing walls, and NOT touching them anywhere. The front wall (divider wall) also stands on the floor, and ONLY touches the new inner-leaf side walls. They support each other. You made need some for of internal bracing or sway bracing for stability, but the idea is to keep everything decoupled: the inner leaf walls only touch each other, and the floor. They are not connected to the existing walls or ceiling in any manner.

I think it is sort of a 'room within a room' with all 2nd leaf walls attached to each other and to the floor but not attached to the existing walls.

Exactly! That is EXACTLY what we are talking about! You got it! :)

One thing is, Around the window and on the right hand (chimney breast) wall and around the door to the house, this will be very difficult to implement and build.

Framing the door won't be a problem, since there will be two back-to-back doors there too (just like the CR-LR door). I agree that the chimney is not going to be easy, but it's not impossible. Take a look at Javier's live room build, to see what "fun" he is having with strange shaped walls that have pillars in them. You'll do more or less the same he is. In any event, that chimney is far enough back in the room where symmetry is no longer so important, so you don't need to be too concerned about that. It does have a large flat surface facing forwards, so that is going to need treatment regardless of what else you do, and we can just include that in the design of the inner wall.

Due to the construction of the existing ceiling, I will not be able to fully decouple the inner ceiling leaf I'm going to build

Why? All you need to do for the new ceiling is to lay joists across the new inner-leaf walls, and put drywall on one side of those joists. Either on top or underneath, depending on how you decide to build.

Thirdly, we are definately planning on staying in this house for the next 3 years at least. After that we may move. I've got to keep the wife happy (you know how it is

You bet! tell me about it.... :) So I'd suggest that you build it in such a way that it can be dismantled easily: Build the framing in sections, and bolt the sections together, instead of nailing them. Build it inside-out so that you have easy access to the bolts, without having to tear apart drywall. Done like that, you can take the sections with you when you move, and maybe even use them again as part of your next studio.... :) !

but would be a lot happier if we didnt fundamentally alter the width of the room

It won't be altered forever, if you build it with dismantling in mind! Build it in sections that are small enough to fit through the doors, and take it with you when you go. Sealing it airtight won't be so easy like this, bit it can be done.

I thought if it was rockwool covered in material all the way around (which is what I assume you would do with an inside out wall), it may make the room very dull as there would be little in the way of reflective surfaces.

True! Which is why you'll be putting slot resonators on a lot of that surface. Slot resonators are basically just thin wooden slats screwed to the framing: The dimensions and spacing of the studs are tuned to give you broadband absorption for problematic frequency ranges, and the wooden slats reflect highs and keep the room live. Also, your floor will remains hard and reflective, and if your bass trapping is taking too much of the highs out, you can wrap it in plastic to help return even more highs to the room. I understand your concerns about it being a "claustrophobic" space, but it doesn't have to be. Lighting and decoration can go a long way to help make it look bigger. Did you see the studio that John designed to fit inside a container? It's even narrower than yours (by a few cm), and it worked out just fine! http://johnlsayers.com/Pages/Spark_1.htm http://johnlsayers.com/Studio/Mainpage/MP-Mark.htm In fact, the dimensions of that container are almost exactly the same as the dimensions of your space, except that you don't have to cut it in order to put in a vocal booth too! So it can be done, and it can look good, without being claustrophobic. Notice the speaker soffits and door between them on John's design.... :) That's the way to do it right.

What do you think?

I think it is doable! I'm kind of tied up today, but tomorrow I should have a bit of time to figure out a good ratio and play around with dimensions and geometry, to see what you can fit in there. - Stuart - PS. This seems to have become your default thread now! Maybe you should just carry on in one thread, and not confuse folks by having several going at once? You already linked back to your other thread from this one, so anyone interested in following your build can still find it easily.

That means that the new 2 leaf dividing wall will have to be attached to the existing outer walls in the live room which would sort of negate the benefits of decoupling it in the control room.....

Once again, you have to live with what you have. It would be great if you could put inside-out walls around the live room as well, and it won't take up any more room than the treatment you are going to have to put in there anyway, but if you absolutely cannot do that (for whatever reason), then you'll have to live with having that side of the divider wall directly attached to the existing walls. But at least your CR will be isolated reasonably well. It won't be optimal, of course, but if that's what your limitations are, then that's what they are. But do take another look at the idea of inside out framing with a single layer of 5/8 on it for your live room.... The space penalty is practically zero....

Soundman2020 wrote:

Quote: I think it is sort of a 'room within a room' with all 2nd leaf walls attached to each other and to the floor but not attached to the existing walls. Exactly! That is EXACTLY what we are talking about! You got it! :)

I cant tell you how happy I was when I read that!!! So, the timbers will take up 2" with a 2" airgap plus 5/8 board then whatever covers the front so approx 5" lost space on each of the sidewalls and across the window....Hmm I'm sold on the idea. For the live room as well. You should have been a salesman ;-)........ Gonna cost a lot more than I thought. I'll price up timber today. A few concerns. 1, Heating. I've got a radiator under the CR window and one in the LR on the right hand side. How the heck would I get these in to the inner structure? 2, Damp/lack of airflow in the outer structure. I have had a bit of an issue with too much condensation in these rooms, especially in the winter. This has lead to a few mould problems. If the airflow is lacking in the outer structure (behind the new leaves) I may suffer with damp problems. Damp / mould can be a nightmare. Is it recommended to heat the outer structure as well as the inner to combat this? I'm sure there are tried and tested methods you are aware of..... 3, The ceiling/roof. I've posted pics to show the current construction. It is already one leaf which is the outer construction of the flat roof mounted on joists. There is currently no insulation between the rooms and the outside world. I took the old plasterboard ceilings down with the aim of insulating this space for both heat retention (England gets very cold in the winter :cry: ), and room treatment. I was planning on using rockwool batts and plasterboarding with soundbloc, using the 10mm neoprene I mentioned earlier to lay along the joists to decouple as much as possible the new plasterboard from the existing structure. I was then gonna leave a 5mm gap around the edge and fill with acoustic caulk. I know this is not a true 2 leaf ceiling structure. Problem is, if I then create a new ceiling below that, it becomes 3 leaf. The wife has been reading the post and is chilled enough to say yeah lets go with the 2 leaf walls but if I try to tell her I aint plasterboarding over those existing joists.....even if I say I'll still pack em with rockwool for insulation.......We may fight!!! :twisted: (The whole 'what will it look like when we move out' arguement will come up again as described earlier :oops: ). The problem is with doing it this way is that the new inner leaf walls will have to attach to the existing joists thru the new plasterboard anyway which I know aint good.....but there are gonna be compromises.....What do you think?

PS, if we're going down this route, I'll have to re-measure everything to include the live room and look at it as one big room initially I think if you agree then take the design from there....

Ok....The measurements in this sketchup I'm posting now are fully accurate. The sketch doesnt look good but it is an accurate template for the room and hopefully something to work with........I'm not very good with sketchup but I'm doing my best :oops: :) Anyway, its the only the dimensions I'm representing with this...... :D PS, I put some doors and windows in but the file size shot up to over 500k so took em back out again.... :oops:

Any thoughts on the ceiling or room ratios Stuart?

Any thoughts on the ceiling or room ratios Stuart?

Hey there Ian. Yup! Lots of thoughts! :) Just not enough time to finish getting them in order and present something coherent. Been tied up lately, but hopefully tomorrow will see a bit of free time... - Stuart -

those soffit panels look awfully small. There's only a couple of inches of solid flat surface around them in some places. I can't see that they'll act much like an infinite baffle, given those dimensions

Oh really? You couldn't get a clue if you swam in clue musk oil and joined a throng of clues doing a clue mating dance. Try telling that to Wes Lachot or Frances Manzella :roll: Maybe they'll take your comments into consideration:roll: what a crock..... :roll:

"Is it recommended to heat the outer structure as well as the inner to combat this? I'm sure there are tried and tested methods you are aware of..... " Air has moisture in it as you are aware. Heated air can hold even more moisture. So to control mold you have to control the moisture. This can be achieved in several ways. The most important place to start is to make certain that the walls you are concerned about are not leaking, wicking, or have cracks that allow drainage from the exterior to the interior. If they do, these are best corrected from the out side, first.

Oh really?

Yup. Really. Like I said: there's only a couple of inches of surface around them, which kind of defeats the whole purpose of simulating an infinite baffle. Really. Not to mention that curious absorber half way down the baffle, which greatly reduces the effective area of the baffle. Hard to see how such a soffit panel can achieve the acoustic purpose of simulating an infinite baffle. Hard to see how it meets the "2x" criteria that you mentioned, as well. :) An infinite baffle, just like the name implies, has to be infinitely large with respect to the wavelengths in question. 2" is hardly "infinitely large", compared to most sound waves! 2 feet would be a lot better, but still fall short of ideal. 2" is large compared to frequencies of 15,000 Hz and higher, which is the top 3 notes of only the highest octave on the scale, and isn't even audible to most people. 2 feet is large compared to frequencies of 1000 Hz, which is half of the entire musical spectrum, and is clearly audible to everyone. 2 feet on each side of the speaker, plus the speaker itself, probably gives you more like 5 feet, which is everything above 500 Hz... So yes, I stand by what I said, despite your ignorant, petty and rather childish comments: those tiny little "baffles" just a couple of inches wide are NOT useful as soffit panels, because they are way too small to have any effect on practically the entire musical spectrum.

Hi, The only place moisture could get in really was thru the small leak that was in the flat roof but I have now had this repaired.....

Soundman2020 wrote:

Oh really?

Yup. Really. Like I said: there's only a couple of inches of surface around them, which kind of defeats the whole purpose of simulating an infinite baffle. Really. Not to mention that curious absorber half way down the baffle, which greatly reduces the effective area of the baffle. Hard to see how such a soffit panel can achieve the acoustic purpose of simulating an infinite baffle. Hard to see how it meets the "2x" criteria that you mentioned, as well. :)

Unless you count the adjacent walls as baffle as well ;) (?!)

:lol: :!:

Any thoughts on the ceiling or room ratios Stuart?

Hey Ian. Did a bit of work on it last night! It's not finished yet, and I'm still working on it, but the good news is that it seems to be reasonable, and I think it's possible to get a decent room out of it, albeit small! The bad news is that there is no room for splaying your walls. It just takes up too much room at 6°. Even at 3°, which isn't really useful anyway, it's just too much to mae the front work. The good news is that there is room for the inner-leaf sidewalls, built inside out, and you can get a decent ratio, too! The good news is that you can get reasonable soffits in there! Not very wide, but good enough, and plenty tall, even with a bit of room for bass trapping where it belongs: behind the lower soffit. The way John does it. The bad news is that you are going to need another desk, quite a bit smaller than the one you mentioned. It's too big in both dimensions to fit comfortably in that small space. Even without the inner leaf or soffits it's already a tight fit, but with them it is out of the question. You might have to custom make a desk, I think, to a shape that fits well. Anyway, I'll do a bit more work on it later to finish roughing it out, then you can finish it off, add extra details, and adjust things to your taste. I thought you'd like to know that it can be made to work, albeit with caveats. :) - Stuart -

Stuart, this is a very much appreciated update!! Thankyou!! I'm getting excited 8) .....

Hey Ian, I'm still working on it, but having a hard time coming up with a ratio that makes sense, since the profile of your room is really close to square (height vs. width). Add to that: trying to use more than about 3 m of the length just makes it really bad. In fact, it puts it in the territory of "Worst case scenario" on Eric Desart's chart! That doesn't mean that your room is no good!!!! So don't get disheartened. It's not the end of the world. It just means that you will need more acoustic treatment in it. You might need some tuned resonators, since you are going to have several modes that are really close to each other, especially if the room ends up being longer than 3.5 m. I was aiming for around 4 m, to give you space for a booth or storage back there, but at anything much more than 3.2 m it starts falling off. Optimum length is about 3.1 m, but the problem then is that your mix position is in a lousy location, and I can't but it any closer to the front wall, since your desk would end up too small. So, to cut a long story short: it is doable, but you'll need treatment to deal with the modes. If only the room wasn't so narrow! Another 30 cm would make all the difference. If only the ceiling wasn't so low! Hmmmmm, thinking of ceilings, can you check the exact height again please, form the floor to the bottom of those joists? I have an idea.... :) - Stuart -

Hi Stuart, Just remeasured. The exact height to the bottom of the joists is 224.5cm. Those lengths you mentioned are a lot shorter than I was hoping for. Its looking like this could work out a lot smaller than I'd anticipated :cry: Since the space is going to be primarily a control room and the back room mainly a practice room with some live recording rather than a lot of live recording, and, given that there has to be some sacrifices to make this work, do you think I should sacrifice good isolation between the rooms for the sake of being able to get better dimensions for ratios in the control room? If we dont do the inside out walls in the control room, this will make for a wider room which seems to be what you are saying would be better. There may then be room for those splays. Control room is number 1 priority. Inside out walls could still be used on the live room side as long as I can comfortably get a drumkit in there. Secondary glazing could be used on the control room window to assist in isolation from outside (which isnt really a problem anyway), attaching the control room leaf of the dividing wall to the existing walls and use inside out walls in the live room with the live room leaf of the dividing wall attached to the inside out walls. I know this goes against the rules and the wall wont be as efficient as it could be but there are gonna be sacrifices and it may work. I'm not sure how this would affect the infinite baffle function of the soffits if it were just soffits, splays and dividing wall but no 'room within a room' on the control room side, if you see what I mean. What do you think? Could this work?