Student Recording Studio Design Feedback

[brobes05]

Hello this is my first post.

I am an architecture student who used to be a musician/recording engineer. Now my task is to design a massive conceptual free-standing 3 story studio. This would not be a problem; however, my school favors abstract building forms. As a result, I am attempting to pack studio program into a non-rectilinear form. I have been drawing inspiration from John's studio floor plans and my professor is very intrigued by the intermediary spaces created from the double walls that do not touch.

I wonder if someone more learned than I can have a look at my floor plans and give me some suggestions. (BTW this will never be built as it would cost 30 million). Regardless, I have a couple of questions: 1) What is the reason the double walls are not parallel at the doors, but rather adjacent which creates these interesting spaces? 2) Are double walls always needed? I know for sound insulation reasoning they are extremely useful in home situations, but my building is freestanding and includes rehearsal studios, publishing offices, public tours, etc... NEvertheless I want to utilize them and don't know whether they should be solely on the exterior of the studio or not.

So, I have started adding double walls but have stopped because I am not sure where they should go. Also, Why double sets of sliding doors? I really like the idea of non-parallel adjacent walls which create quite interesting shapes in between.

Attached are my floor plans and a render of the abstract exterior.

Thank you in advance and I hope to make an excellent project that makes sense!

Erik

[brobes05]

Sorry, but I don't think my plans showed up. Here they are:

[Soundman2020]

Hi Erik. Please read the forum rules for posting (click here). You seem to be missing a couple of things!

my professor is very intrigued by the intermediary spaces created from the double walls that do not touch

That's the very basis of how studios are isolated successfully at low cost. Without that, the only other choices are extremely massive walls, as in very thick concrete, multi-leaf walls that are not very effective in low frequencies, meaning that a large amount of space would be taken up by each wall to compensate for that, or currently unknown alien technology...

have a look at my floor plans and give me some suggestions.

Both of your options would work, but it looks like the second one would have better sight lines: There is good visibility between all rooms, with very little or no hidden areas, assuming careful placement of glass.

On the other hand, the upper one makes better use of space, and has a much larger live room, so that's also good. It also eliminates that nasty curved wall in the live room, which would give you lots of trouble with the acoustics, and would need some interesting treatment. So from that point of view, the top one is better. The CR is also a bit bigger, and would be better shaped if you wanted to use the room for mixing 5.1 or other multi-channel formats. But I would not chop off the rear corners like that: those are very valuable for bass trapping.

In both cases, I would double check the room geometry (speaker / listening position / room relationship) to make sure it is optimal: it doesn't look like it, from the views you show.

1) What is the reason the double walls are not parallel at the doors, but rather adjacent which creates these interesting spaces?

Sometimes it just works out better that way, form purely structural or architectural points of view, but isn't really needed from the acoustic point of view. John himself explains why he often did that in the past, but doesn't do it so much now: http://www.johnlsayers.com/phpBB2/viewt ... 15&start=4

2) Are double walls always needed?

If you want good isolation at reasonable cost, then yes. ("isolation" is sometimes incorrectly called "soundproofing". There's no such thing as true "soundproofing", and in any case, the word itslef means different things to different people, so most acousticians use "isolation" to refer to methods for preventing sound from getting from "A" to "B").

I know for sound insulation reasoning they are extremely useful in home situations,

Not just home situations: Any situation where you need good isolation at low cost.

but my building is freestanding and includes rehearsal studios, publishing offices, public tours, etc...

Great! Then only isolate the rooms that need it, and build the other ones conventionally. So your offices, lobby, bathrooms, etc. would be done normally, and the actual studio would be done with two-leaf MSM isolation. Meaning the control room, live room, isolation booth, and rehearsal room. Those can be grouped together in one area, so you'd only need one "outer leaf" isolation wall around all of them, then build each of the rooms individually as free-standing single-leaf room that does not touch any other room, and nor does it touch the outer leaf in any place. That would simplify the overall design and construction, and reduce costs.

So, I have started adding double walls but have stopped because I am not sure where they should go.

As above: Imagine the "studio" part of that floor as being an isolated section, cut off from the rest of the rooms on that floor by a single-leaf isolation wall. The wall itself might be made up from several layers of building materials to get to the required mass and other properties, but they would all be in direct contact with one another, with no air gaps between them. That would be your "outer leaf" that surrounds all of the rooms that need isolation. All rooms where "noisy" things would be happening, or very quite things would be happening.

The within that shell you would build each room as a self-contained stand-alone structure that does not touch any of the other rooms, nor does it touch the outer-leaf. Not any any point. Not even a single nail, screw, pipe, or piece of wire. Each room is built as a single leaf that is fully "decoupled" from all other rooms, mechanically. Here too, that leaf might be made up from several layers of building materials (EG. drywall, OSB, plywood, etc.) to get the right characteristics, but all of those layers would be in direct contact, with no air gaps between them. The only air gap for each room, is the one between it and the outer leaf, or between it and the adjacent room.

This type of construction is often called "fully decoupled two-leaf MSM isolation". It is based on a principle of physics known as "Mass-Spring-Mass", hence the "MSM" part of the name. The rest is self-evident: there are two leaves, and they are fully decoupled from each other, and that's how the isolation is obtained. The equations of physics that deal with Mass-Spring-Mass systems is applied to the walls, in order to determine how much mass is needed on each leaf, and how big the air gap needs to be, and how much damping is needed, to meet the design criteria for the wall, in terms of what frequencies it must isolate, and how well it must isolated them.

Also, Why double sets of sliding doors?

One door in each leaf! Since each room is built as a "2-leaf" system with respect to all other rooms, you need one door for the inner leaf of the room, and another door in the outer-loaf, and of course that "outer leaf" is either the inner leaf of another room, or it is indeed the actual outer-leaf that envelopes all of the rooms. Either way, you need two doors.

I really like the idea of non-parallel adjacent walls which create quite interesting shapes in between.

I wouldn't worry about those shapes at all: they will never be seen after the studio is complete. They would all be totally hidden from view, inside the cavities between the walls. Nobody would ever notice! They only place you'd ever see then, is on the plans and drawings...

Non-parallel walls inside a room are a different thing, of course, and can be useful acoustically, if they are designed with specific purposes in mind. For example, in a live room they can eliminate flutter echo between opposite walls, provided that the angle is greater than 12°, and they can also modify the modal behavior of the room, making it more complex, which can be good for some issues. They can also be used to control reflections, which is very commonly done in control rooms, especially ones that follow the RFZ, CID, or NER control room design concepts, as well as for the older but now obsolete LEDE design concept.

But having the walls of a room non-parallel does not mean that the MSM system also has to be non-parallel. As I mentioned before, sometimes it ends up that way (which implies wasted space), but there is no acoustical need for that to happen. It's fine to keep the MSM walls parallel, which minimizes lost space, and also makes the calculations simpler. You can angle them if you want, and there are some minor benefits from doing that, but as John says, it isn't necessary.

You might find this paper interesting: https://app.box.com/shared/jcaoavdc8g It's very old (from 1973) but lays out the principles behind MSM construction. They use slightly different terminology, but you'll get the idea easily.


- Stuart -

[brobes05]

Thank you so much for your informative reply!
Sorry for not following the specified posting protocol.
This has been immensely helpful and I have been updating my plans and
studying the links you have provided.

Thank you again ! Immensely helpful.

Best,
Erik

[JCBigler]

Erik, I hope you stick around here and learn and contribute.

It would certainly be nice to have some architects out there in the world that understand acoustics and functional uses for spaces, rather just making pretty looking objects.

I'm currently consulting on the live audio portions of a conference center, which is parallel glass walls, with a stone floor and stone walls on either end. The architects were like, "well, I guess we could do some kind of acoustic absorption on the ceilings...if you really think it needs it"

[Soundman2020]

"well, I guess we could do some kind of acoustic absorption on the ceilings...if you really think it needs it"

Naaah, it'll be absolutely perfect without.... provided that nobody ever wants to hear anything at all inside!

Actually, for a space like that, you might want to look into some of the modern transparent micro-perforated sheets, and some other types of metal perf panel that can be disguised as architectural features. They work really well, and look good too, without seeming to he acoustic at all.

- Stuart -

[brobes05]

continuous diffuser.PNG

Thanks again glad to be here.
I had a quick question. Is it possible to create a continuous surface sound diffuser where the wall and ceiling diffuser is one surface? attached is an image. I know this may be unorthodox, but I wonder. Thank you in advance.

[Soundman2020]

You could do that, yes, but that design would create "lobing" artifacts in the diffusion pattern, in both intensity and phase (time), since the surface convolutions (peaks and valleys) follow a regular pattern. It would also be a broadband device, since the size of the convolutions varies from being close together in one place, to far apart in other places. In fact, that design would be more of a scattering device than a diffusing device. I'm not sure you'd want to do that. It would also be very complex to build, and very VERY complex to understand mathematically, in order to predict what effect it would have on the room acoustics.

Diffusers are normally designed using semi-random patterns of wells and protrusions, so they can be tuned to specific frequencies as needed while avoiding lobing. Most such devices these days are based on QRD principles (Quadratic Residue Diffusion), which uses quadratic equations to define the patterns of "peaks" and "valleys".

Here are a couple of pictures of what these types of diffusers look like. They can be either 1D diffusers, sometimes called Schroeder diffusers, like this:

qrd-diffuser.jpg

Or the math also works in 2d, which is better in some ways, and results in diffusers that look like this (sometimes called "skyline" diffusers):

S3-Control-Room-Rear-QRDs.jpg

Diffusers-Skyline-SDing-0094 - Copy.jpg

BIG-DIFFUSER-cmmroom.jpg

2d-qrd-diffusers-in-studio.jpg

That's not the only way that diffusers can be made: not by any means! Those are the easiest to design and calculate, and fairly simple to build as well, but they can get quite complex and crazy too, if you want, like this:

crazy-looking-ceiling-diffuser-Kiev recording studio.jpg

But whatever you do, it MUST be designed acoustically for the room. You can't just put any old diffuser in any room, just because it looks nice, and hope it will work! Each one has to be designed specifically, to solve the acoustic problems of the room without creating any new problems.

Even if your project is just a "paper" design, not one that will actually get built, it still needs to have acoustic devices that are acoustically suitable for each room. It would not be realistic if it did not.



- Stuart -

[brobes05]

Thank you Stuart for your informative reply. Most of what you have said makes sense. I don't think I would want to create a complicated scattering device like that the one I proposed. My instructor has been pushing for me to create a seamless wall to ceiling panel, but I have not found a precedent other something zaha hadid has done in a large concert hall. The precedent I have found is similar to the diffuser images you have sent me.

I suppose I ask what the relationship is between the wall to ceiling panels? It seems from the examples I have been studying in studios that there are wall diffusers as well as ceiling treatments that are usually a different shape/pattern. Does this always have to be the case? Can they be the same? In your last example they are extremely different.

[Soundman2020]

They can be the same if you want them to be the same, to a certain extent, and provided that you design them very carefully, but normally they are different, as they serve different purposes, and are faced with different frequencies and incidence patterns.

- Stuart -