John Sayers' Recording Studio Design Forum Archive

Notes on current construction:

We are a small film school looking to upgrade our sound facilities. We are looking at using basement spaces in a Victorian era building. Lots of brick in the structural walls. Unfortunately there is a fair amount of mechanical pipe through the ceiling, that may be a show stopper, I don't know. We have two sound mixing spaces currently, both highly problematic for different reasons. I'm hoping to solve at least the major problems and have two decent functional spaces by the end. Any advice given is greatly appreciated. We had originally designed sound rooms for another part of the basement, for a previous reno, but unfortunately money ran out before they got done. Now those spaces have been re-purposed and we can't put our rooms there.

• Current recording room has 36dB ambient machine noise (not normal)
  Current mixing room has 39dB ambient machine noise, nothing but drop ceiling.
  Pipes are insulated, but obviously not enough?
  Building manager tells me we currently have something dysfunctional in the boiler room which is the root cause of the noise, and we should be able to fix it. I don’t remember hearing it before, so I’m hoping he’s right (and that it’s not expensive).
  
  None of the current spaces are serviced by the buildings HVAC, there are moisture problems in the current sound room (we run a dehumidifier when room is not in use), so I would like to get it hooked up.
  
  Walls of building are thick brick and mortar and basement is partially below grade. Windows shown in plan are all filled in.

Generally students are using the space to mix sound for their film projects - using a target of between -12 and -6dB. We are using some medium sized near field monitors (Yorkville YSM1p) in a stereo configuration. Sometimes music is recorded, or other sound art produced.

Current Setup
004 is the current sound mixing and recording space.
Mixing is approx. 10’8 x 12’ x 7’6 (drop ceiling)
ADR/Foley Recording is approx. 10’2 x 9’8 x 9’. does have double leaf drywall construction of some sort, including ceiling (I didn’t oversee construction). Double glass windows, double doors. Sound is dampened pretty good between the two spaces, but it isn’t completely sound proof. It doesn't necessarily need to be,but obviously as much isolation as possible is desirable. This room is sometimes used for music recording, but not often. Voice and sound effects are it's main purpose.

003 is the computer lab we’d like to change to a mixing space. Approx 26.5 x 18 x 10.5 to lath and plaster ceiling above (pipes to deal with) approx 8’ to bottom of lowest pipe. The circle is a structural post, circular metal (iron?).

002 is a computer lab (it does not have access to 001 as depicted, the doorway is covered over)

005 is the boiler room At least there is a heavy brick structural wall, except of course all the pipes running through it to other parts of the building.
003: Currently a dysfunctional computer lab
Ceiling cleanup required for sure. Not all the pipes are actually connected and can be removed completely. Quite a lot of the piping is sprinkler (noted on the sketchup drawing as grey. The heating pipes are coloured in red). We have so much sprinkler pipeing to meet code - there needs to be heads below the drop ceiling and also coverage inside the cavity of the drop ceiling because of how large the space is. We may be able to remove the lower series of sprinklers with the new reno.
004 Mixing space as you enter. Recording access space is through, to the left of the window.
004 View through ceiling - the people who designed and installed this room didn't think a mixing space needed to have ceiling insulation. :/
004 Recording booth door view
004 Recording booth reverse view
004 Detail of pipe insulation. This is a heating pipe coming from the boiler room. Notice the pipe branches UP (floor above?), to the LEFT (service basement?), and to the RIGHT (back to boiler room).


Simple plan for construction
Put a hallway in 003 so access to 002 and 004 is unobtrusive. Expand 004 so the mixing space is no longer a cube. Proper double leaf shell for 003. diffusion and reflection treatments may be done at a later time if budget doesn’t cover it. The drop ceiling will be removed in both 003 and 004 mixing and new drywall with isolation treatment will be hung from the original lath ceiling. 004 probably needs a new wall between it and 003 - I think it's currently just a regular drywall construction.

003 dimensions will be approx: 20 x 16 x 9
004 mixing will be expanded to approx: 16 x 12 x 9

9' height is assuming we can deal with those pipes!

Purple = current 002 space
Cyan = expansion of 002 Mixing
Yellow = Maximum double leaf envelope for 003 (planning to sketch a maximized golden ratio envelope as well)
Brick = structural brick walls of the building (ext. and int.)

Known:
Budget is $30k CAD
Current spaces are very dysfunctional, need spaces optimized for film audio work (if 003 could work as a stereo and 5.1 mixing space, that would be ideal)
Boiler room gives off a lot of machine noise.

Known unknowns:
Floor/Subfloor construction (will try to check with a scope)


Cost:

1. 1. moving sprinkler pipes
   2. removing legacy mechanical/cleaning up wires
   3. installing HVAC drops
   4. Installing double leaf construction where required
   5. Extending current electrical through new walls
   6. 3 new doors required (004 mixing has a single entrance door currently)

Questions:
Best strategy for sound isolation -
1. two leaf for each enclosed space?
2. can the spaces share a two leaf wall?
3. Is more air space between the two rooms helpful?

Can this be done in phases effectively? (can we build 003 as a decently isolated space and revisit 002 at a later date?
*Is it cheaper/better to demo the whole thing and start over (keeping our low budget in mind)

Layout (which items should I be aiming for? I've currently gone with #1 but I'm feeling like that's not the best):
1.Maximum air space
2.Golden Ratio
3.Angled walls

How much does a HVAC damper help to isolate sound? Is the design pictured below the sort of thing I should be aiming for? Should this be placed outside the double leaf walls? I wanted to include my sketchup model, but seem to have trouble uploading it directly. I will link to it off site, and if anyone has advice for embedding it I will give it another shot:

Sketchup Model via Google Drive

Well thanks to anyone who's made it this far, and I do appreciate any and all feedback! Hoping to give the students a great new resource...

Here are some illustrations of the pipes in the ceiling, as far as I could measure and see them. I have not included orphan pipes or a large electric heater which is currently mounted in the drop ceiling of 003.

Hi Nathan, and Welcome to the fourm!

You certainly have an interesting and complicated situation! But there is hope. It probably can be made very good, depending on what your specific goals are.

there is a fair amount of mechanical pipe through the ceiling, that may be a show stopper,

Not necessarily a show-stopper. You mentioned further on that some of that piping is not used and can be removed, but other parts are required by code, as part of the fire system. How much of a problem that is depends on how much isolation you need. How feasible the solution is, depends on how much you are prepared to spend to get that level of isolation.

If you only need moderate isolation, then this isn't too much of a problem. If you need high isolation then it is more of an issue, and would cost more to deal with. So it's really a trade-off of needs vs. cost.

We have two sound mixing spaces currently,

We tend to call those areas "control rooms", to standardize on terminology. It helps to avoid confusion.

Current recording room has 36dB ambient machine noise (not normal)

How was that measured? There's a big difference between "C" weighting and "A" weighting, and depending on the type of ambient noise, there can also be a big difference between "fast" and "slow" response settings.

Current mixing room has 39dB ambient machine noise, nothing but drop ceiling.

Same applies here: It is important to know if that is 39dBA or 39dBC (or maybe even something else?).

Also, ambient noise levels in studios are more commonly defined in terms of NC curves or NR curves, which tell you something about the noise spectrum as well as its level. 39 dB by itself does not tell you anything about the spectrum, which is just as important as the actual level. There's a big difference in how humans perceive a level 39 dB with most of the sound at around 4kHz, vs. 39 dB with most of the sound around 100 Hz.

Pipes are insulated, but obviously not enough?

Pipe insulation is for thermal purposes, not acoustic. Just putting insulation on a pipe does practically nothing to reduce sound transmission. It's a common misconception that insulation by itself makes a good sound barrier: in reality, it makes a lousy sound barrier. When used as part of an isolation SYSTEM, however, insulation can be very effective. The whole is greater than the sum of its parts.

Building manager tells me we currently have something dysfunctional in the boiler room which is the root cause of the noise,

Did he tell you what that "something" is, and in what way it is "dysfunctional"? That's important to know! It is by far cheaper and easier to solve sound isolation issues at the source, than at the destination. If you can found out what is causing that issue, then we can help you figure out how to deal with it right there, in the boiler room, rather than try to deal with it in the studio isolation plan.

None of the current spaces are serviced by the buildings HVAC

Would it be possible to tie in to the building HVAC system? Does the building HVAC system have the capacity to handle your rooms, in addition to the load it is already carrying? It might be cheaper to connect to that than to implement your own HVAC system. However, if the building system does not run 24/7, then you might need your own anyway: film studios often keep strange hours, well outside normal office hours, and building administrators often shut down HVAC systems at night and over weekends, either partially or completely. So I'd check if you can hook into that system, but also if it will be running at the times you need it!

there are moisture problems in the current sound room

That needs to be solved before you do anything else at all. You need to get an expert in to figure out where that humidity is comping from, and fix it completely, before you can do build the studio. Isolating a studio implies putting up hermetic walls would trap the humidity inside the wall cavities, where it will slowly but surely destroy the walls from the inside, and create numerous very expensive problems for you over time. This should be your number one priority: find the source of that moisture problem, and spend whatever it takes to fix it permanently.

we run a dehumidifier when room is not in use), so I would like to get it hooked up.

Sorry, but that isn't the solution. If you have to run a dehumidifier then the problem is serious, and implementing an HVAC system will not solve it. HVAC only addresses the rooms themselves, but not the cavities in the walls between them. That's where your fungus, mold, rot and other nasty issues will happen: inside the walls, where you will not be aware of them until it is way too late. HVAC is not the solution to humidity problems. HVAC is highly necessary, yes, but it is not the correct way to deal with the issue.

basement is partially below grade.

That might be part of the issue with the moisture: Are the walls or floor damp to the touch? Is there visible water or condensation anywhere? You need to get an expert in to figure out the reason for this problem, and do whatever repairs are needed before doing anything to the studio. Any money you spend building the studio would just be thrown in the trash basically, if the humidity problem is not located and fixed first.

students are using the space to mix sound for their film projects - using a target of between -12 and -6dB.

It looks like you forgot to complete that sentence! "-12 and -6 dB" relative to what? What levels are you referring to there?

004 is the current sound mixing and recording space.
Mixing is approx. 10’8 x 12’ x 7’6 (drop ceiling)

That's VERY small for a control room! And even worse, the ceiling is very low. Specifications from SMPTE Dolby, the AES, ITU and EBU regarding critical listening rooms all suggest a minimum of at least twice that floor area, with a 10 foot ceiling. It would not be easy to use that room for a decent control room.

ADR/Foley Recording is approx. 10’2 x 9’8 x 9’.

That's also VERY small for a Foley stage. Very little room to have a good selection of pits in there. Question: Do you have a water pit in there? That might be part of your humidity problem! If you do have a water pit, then that would need to be taken into consideration in the HVAC plan, since there would be a very large latent heat load issue in there, in addition the sensible heat load. Are your pits sunk into the actual concrete floor, or are they just boxes placed on top?

Isolating a proper Foley stage is a big deal.

Sound is dampened pretty good between the two spaces, but it isn’t completely sound proof. It doesn't necessarily need to

A true "Foley for film" stage DOES need to be isolated, to a very high level. Foley implies recording very quiet things, then increasing the level hugely to add it it the sound track. Even slight background noises become a thundering roar in the mix, if the room isn't isolated to very high levels. A Foley stage is about the toughest possible thing to isolate. You really need something like NR-15 or lower (roughly the same as NC-15).

003 is the computer lab we’d like to change to a mixing space. Approx 26.5 x 18 x 10.5

That's a MUCH better size for a control room! That would be ideal.

The circle is a structural post, circular metal (iron?).

That's a problem, but not necessarily a big one. It can probably be moved. You'll need a structural engineer to take a look at that, and tell you what needs to be done to move that pole. It can be done: I have done it before, even for home studios. The cost doesn't have to be prohibitive either, but it absolutely must be done with the blessing and guidance of a qualified structural engineer.

004 Mixing space as you enter.

That needs fixing! If you plan to keep that room as a control room, then there are many issues with the current layout that would need to be dealt with, to make it usable.

004 View through ceiling - the people who designed and installed this room didn't think a mixing space needed to have ceiling insulation.

They also didn't think that a control room needs any isolation at all! That open panel shows that there is NO isolation for this room, and no treatment either!

004 Recording booth door view

You said that this is a Foley stage, but I don't see any signs of that in the photo: Where are the pits? Was that photo taken when the room was NOT set up for Foley work? Pits taken out and stored somewhere?

004 Detail of pipe insulation. This is a heating pipe coming from the boiler room.

That's purely thermal insulation. No acoustic isolation at all. Pretty much all noises in that pipe will be heard in the room, and any loud noises generated in the room could also potentially flank through those pipes to other rooms.

Simple plan for construction

I'm trying to mentally correlate that drawing with the previous drawing, but not having much success! The two areas appear to be different shapes and sizes...

Proper double leaf shell for 003.

I don't see that shown on the plan at all. Maybe you could highlight the inner and outer leaf for that room in different colors, to clarify the plan?

diffusion and reflection treatments may be done at a later time if budget doesn’t cover it.

That room is waaaaaay too small to need diffusion or reflective treatment! It will need mostly absorption. Practically all absorption, in fact. I could run the numbers for you to be certain, but at a rough guess you are going to need absorptive treatment on well over 50% of the wall and ceiling surfaces. Diffusion is out of the question for that room: numerically-based diffusers can only be used successfully in rooms that are much larger than that. The lobing artifacts make it untenable for small rooms.

The drop ceiling will be removed in both 003 and 004 mixing and new drywall with isolation treatment will be hung from the original lath ceiling.

Why? I mean, removing the drop ceiling is most certainly necessary, but if there's another ceiling up there already, then adding a new one below it would likely create a 3-leaf system. Not a good idea, if you need isolation for low frequencies.

004 probably needs a new wall between it and 003 - I think it's currently just a regular drywall construction.

This is where I'm confused about your isolation plan. A few paragraphs up you mentioned that 003 will get a proper two-leaf isolation wall, yet here you mention that in addition to that you think 004 will get a new wall! That doesn't make sense. A proper isolation system around 003 automatically implies modifying the wall to 004, which is adjacent! There's no other way of doing it.

if 003 could work as a stereo and 5.1 mixing space, that would be idea

That's possible, yes. If you plan to do 5.1 in there, then the room needs to be designed from the start for 5.1 Trying to retrofit a 2.0 or 2.1 room for 5.1 is not something you want to do, but there's no problem at all in doing 2.0 or 2.1 in a room designed for 5.1, even if the 5.1 systems is not yet installed.

Installing double leaf construction where required

There seems to be a misunderstanding or misconception here, about how double-leaf construction works. You can't just install it where you feel like: if you want to isolate one room properly, using two-leaf isolation, then the entire room needs to be isolated that way: all four walls, and the ceiling, and possible the floor too. That implies taking the point of view of someone standing inside the finished room, and then confirming that there are ONLY two leaves between that person and ALL of the adjacent rooms: Not one leaf, not three leaves, or four, or any other number: there can be two leaves, only two leaves, and nothing but two leaves, in all directions. One of those leaves will be the drywall facing the person inside that room, and the other leaf will be drywall (or brick) facing the person in the adjacent room. Period. End of story. So if you work your way through this mentally, and you count more than two leaves in any direction, then you did something wrong: you don't have an isolation system.

So for example, if we are talking about going upwards from your room to the one above: you have the ceiling in your room, plus the existing ceiling above, plus the floor right above that. That is THREE leaves, so there's a problem right there. Something wrong. And if you were to put a two-leaf wall around 003 plus also a 2-leaf wall around 004, then you would have FOUR leaves between the rooms: that's very wrong. A three leaf system or a 4 leaf system will have a much higher fundamental resonant frequency that than a two leaf system of the same mass and total thickness. Always. And if the resonant frequency is higher, then the low frequency isolation is worse.

Extending current electrical through new walls

That also isn't possible, if you want good isolation between rooms. There can be no holes at all in the leaves the define the rooms. You can allow just one single penetration to bring in the power feed, then all the wiring for the room must be done using surface-mount "trunking" systems. The electrician cannot, under any circumstances, cut holes in the drywall like he normally would to install boxes for outlets, switches, lights, etc. All of those can only be surface mounted.

1. two leaf for each enclosed space?

Yes. That's the only way to get good isolation at low cost. But it isn't done as "two leaves for each room". Rather, it is done such that "between the interior of each room, and the interior of the next room, there are only ever two leaves, in any direction".

2. can the spaces share a two leaf wall?

It's not they the "can" do so. Rather, it is that they HAVE TO do so! There is no alternative, with correct two-leaf construction. So between your control room and your live room, you have drywall on the control room side, drywall on the live room side, and a gap between them. That's it: two leaves. The same applies in all other directions.

3. Is more air space between the two rooms helpful?

Most definitely! The equations for calculating the resonant frequency of a two-leaf system have only three major variables. One of those is the depth of the air cavity. The larger the cavity, then lower the frequency. The other two variables are the mass of each of the leaves, and how much damping (insulation) is in the cavity. Increasing any of those gives you a lower frequency, and better isolation. So more mass, more damping, and more depth are all good things.

Can this be done in phases effectively? (can we build 003 as a decently isolated space and revisit 002 at a later date?

Possibly, but not easily, and not cheaply. Unless you go with your own very next suggestion below...

*Is it cheaper/better to demo the whole thing and start over (keeping our low budget in mind)

Very likely, yes. In the demo, if you do it carefully, you can probably re-use a lot of the materials. Complete demo and re-build would allow you to build all of the walls as proper two-leaf MSM systems without trying to retrofit bits and pieces, and without being restricted by existing walls, doors, windows and other items. You would likely also not need to move that pillar, since you could re-design the rooms so that the pillar ends up inside one of the walls, in the cavity between the leaves. With a full demo, you'd also have good access to all the pipes, electrical and HVAC, as well as to the existing ceiling above, to deal with the issues associated with that. It would also make it a lot easier to figure out where your humidity problem is coming from, and to fix it properly: There are a lot of "pros" to this approach, and very few "cons".

Layout (which items should I be aiming for? I've currently gone with #1 but I'm feeling like that's not the best):
1.Maximum air space
2.Golden Ratio
3.Angled walls

All of the above! And none of the above!

Sorry to be so cryptic, but studio design isn't about choosing one thing over another: it is about looking at all of the issues, getting the "big picture", then designating the best possible layout within that space, with as few compromises as possible. There will be compromises (there always are!), but there is no need to compromise any of the above. You can angle the walls that need it, at the best angles, and still have enough air space inside the walls to get the isolation you need, and also have a good room ratio. Those don't need to be traded off. There might be other trade-offs to get there, but these don't have to be.

Also, there is no such thing as a perfect "golden ratio" for a recording studio. That's a myth. In reality, there are many good ratios (a couple of dozen) that have be figured out be acousticians such as Sepmeyer, Louden, Bolt, Volkman, Bonello, and others. Each has its advantages and disadvantages, and each is suited to some studios better than to others: None of them is perfect, none of them is "golden", and none of them is better than any of the others for all situations. That's part of good studio design: choosing the ratio that makes the most sense for each project. Arguably, one could say that Sepmeyer's best ratio is preferably for most cases, but even then, that would not be accurate.

How much does a HVAC damper help to isolate sound?

Your picture does not show an HVAC damper. This is what HVAC dampers look like:

Damper for round duct:
Damper for rectangular duct: Your picture shows an HVAC silencer box, or baffle box, or muffler, but it is built incorrectly: the interior lining should only ever by done with proper duct liner, never with fluffy insulation. Over time the air flow will erode that, and you'll end up with fibers all over your studio...

But to answer your question: A well designed and well built HVAC silencer can isolate sound VERY well. It uses several acoustic principles at once to do so, and the insertion loss can be quite high. However, the rest of the HVAC system needs to be designed in conjunction with the silencer: Even the best silencer in the world won't do much if the rest of the system is lousy: For example, if the flow velocity is too high, then the silencer won't achieve much since all of the noise will come from turbulent flow in the ducts and registers. And if the transition from duct to silencer and back again is not sudden enough, or does not involve a large enough difference in cross-section, then you won't get the necessary impedance mismatch, so you won't get good isolation, even of the silencer itself is well designed. HVAC is a system, and all of it has to be designed correctly.

Is the design pictured below the sort of thing I should be aiming for?

Concept: Yes. Implementation? No. The idea is roughly correct, but that's not the right way to build one.

I wanted to include my sketchup model, but seem to have trouble uploading it directly

There's a limit on the size of files that can be uploaded to the forum, and many SketchUp models are bigger than the limit. So uploading externally then positing a link is the right way to do it.

I'm downloading it now, and I'll take a look. If I see anything additional, I'll add another comment later.


- Stuart -

Soundman2020 wrote:Hi Nathan, and Welcome to the fourm!
You certainly have an interesting and complicated situation! But there is hope. It probably can be made very good, depending on what your specific goals are.

Thanks for the glimmer of hope! I've been reading as much of the forums as my time allows, and have been learning a lot, but alas not enough it seems!

Specific goals are:
Two control rooms (see, I am learning!) capable of mixing 2/2.1 minimum in a predominately film environment. Ideally one would be 5.1 capable.
ADR/Foley recording room attached to one of the control rooms.

Soundman2020 wrote: Not necessarily a show-stopper. You mentioned further on that some of that piping is not used and can be removed, but other parts are required by code, as part of the fire system. How much of a problem that is depends on how much isolation you need. How feasible the solution is, depends on how much you are prepared to spend to get that level of isolation.

All the piping I have drawn is stuff that has to stay, other piping can and will be taken out. The sprinkler piping will have to be reconfigured to match the new space (higher ceilings). I will have to check with the building code to see if we still need double sprinklers, or if there will be a small enough cavity to not require it. I will be checking with trades people on the cost of moving the sprinklers, and see if raising or moving the hot water pipe is feasible. Running it down the new hallway would be ideal, as opposed to through *all* the sound spaces.

I have a specific budget that administration has set aside - $30k Canadian. It may be woefully inadequate for the task at hand, it's starting to sound that way

Soundman2020 wrote: If you only need moderate isolation, then this isn't too much of a problem. If you need high isolation then it is more of an issue, and would cost more to deal with. So it's really a trade-off of needs vs. cost.

Our current control rooms are a joke, even as a someone who isn't highly educated with regards to sound, I recognize this. I'm trying to get something functional that makes the students feel like they aren't in their mom's basement.

Soundman2020 wrote:Current recording room has 36dB ambient machine noise (not normal)

How was that measured? There's a big difference between "C" weighting and "A" weighting, and depending on the type of ambient noise, there can also be a big difference between "fast" and "slow" response settings. [/quote]

I think it's A weighting, but it just came from an app on my phone:
https://play.google.com/store/apps/deta ... ound&hl=en

They say it was calibrated to a A weighted meter. If this is unacceptable, I can probably get a meter from Amazon fairly quickly, or maybe find one to borrow.

If I were to buy one, would something like this be better:
http://www.amazon.ca/Pyle-Meters-PSPL03 ... ibel+meter

Soundman2020 wrote: Also, ambient noise levels in studios are more commonly defined in terms of NC curves or NR curves, which tell you something about the noise spectrum as well as its level. 39 dB by itself does not tell you anything about the spectrum, which is just as important as the actual level. There's a big difference in how humans perceive a level 39 dB with most of the sound at around 4kHz, vs. 39 dB with most of the sound around 100 Hz.

A decibel meter wouldn't give me information on the spectrum, would it? Could I do a recording with our Sound Devices 788t and a cardioid mic and look at the spectrum in audio software, or do I need another device?

Soundman2020 wrote:Pipe insulation is for thermal purposes, not acoustic. Just putting insulation on a pipe does practically nothing to reduce sound transmission. It's a common misconception that insulation by itself makes a good sound barrier: in reality, it makes a lousy sound barrier. When used as part of an isolation SYSTEM, however, insulation can be very effective. The whole is greater than the sum of its parts.

I understand - we would need to do drywall+insulation enclosures around the pipes to properly isolate them, yes?

Soundman2020 wrote:Did he tell you what that "something" is, and in what way it is "dysfunctional"? That's important to know! It is by far cheaper and easier to solve sound isolation issues at the source, than at the destination. If you can found out what is causing that issue, then we can help you figure out how to deal with it right there, in the boiler room, rather than try to deal with it in the studio isolation plan.

I'm definitely going to get to the bottom of this, because I know this rumble is a recent development. We took a quick listen in the boiler room and I could "feel" the noise, but couldn't track it down. We will go in early next week and shut the whole system down, and restart individual components to track down the source. He figures it's probably a bearing assembly on one of the many fans/pumps, which could be replaced with minimal fuss. We just have to find it.

Soundman2020 wrote:Would it be possible to tie in to the building HVAC system? Does the building HVAC system have the capacity to handle your rooms, in addition to the load it is already carrying? It might be cheaper to connect to that than to implement your own HVAC system. However, if the building system does not run 24/7, then you might need your own anyway: film studios often keep strange hours, well outside normal office hours, and building administrators often shut down HVAC systems at night and over weekends, either partially or completely. So I'd check if you can hook into that system, but also if it will be running at the times you need it!

Our HVAC is overpowered for this building, it's a fairly new install - less than 5 years old and not all the building is connected to it currently. There is plenty of oomph left for these small rooms. It runs 24/7. It's a very high end system with each zone (individual rooms which are connected) using electronic controls for heating/cooling/fan.

Soundman2020 wrote:That needs to be solved before you do anything else at all. You need to get an expert in to figure out where that humidity is comping from, and fix it completely, before you can do build the studio. Isolating a studio implies putting up hermetic walls would trap the humidity inside the wall cavities, where it will slowly but surely destroy the walls from the inside, and create numerous very expensive problems for you over time. This should be your number one priority: find the source of that moisture problem, and spend whatever it takes to fix it permanently.

That might be part of the issue with the moisture: Are the walls or floor damp to the touch? Is there visible water or condensation anywhere? You need to get an expert in to figure out the reason for this problem, and do whatever repairs are needed before doing anything to the studio. Any money you spend building the studio would just be thrown in the trash basically, if the humidity problem is not located and fixed first.

It's a old brick building and we're below grade. Doesn't take an expert to know the walls are wicking moisture out of the ground. In addition this is a port city, and we have very high humidity, especially in the summer. Even if the walls were dry humidity will just collect in the basement. That's a big reason I want HVAC connections - it'll help dry up the air. If we go the complete demo route, we can do vapour barrier on the outside walls - should solve the moisture problem, and might help with further isolation from the outside world?

Soundman2020 wrote:

students are using the space to mix sound for their film projects - using a target of between -12 and -6dB.

It looks like you forgot to complete that sentence! "-12 and -6 dB" relative to what? What levels are you referring to there?

I was speaking of the software. Our monitors are calibrated to -12dB (FS?) in the software = 73dB (A weighted I think?) or 0dB(FS?) = 85dB

Soundman2020 wrote:That's VERY small for a control room! And even worse, the ceiling is very low. Specifications from SMPTE Dolby, the AES, ITU and EBU regarding critical listening rooms all suggest a minimum of at least twice that floor area, with a 10 foot ceiling. It would not be easy to use that room for a decent control room.

That's also VERY small for a Foley stage. Very little room to have a good selection of pits in there. Question: Do you have a water pit in there? That might be part of your humidity problem! If you do have a water pit, then that would need to be taken into consideration in the HVAC plan, since there would be a very large latent heat load issue in there, in addition the sensible heat load. Are your pits sunk into the actual concrete floor, or are they just boxes placed on top?

There are boxes stored elsewhere that student use at various times. It would be nice to incorporate some better storage into the floor plan, but I'm not sure where that would go at this point, since we're already so cramped. ADR is what the space is used for %90 of the time.

Soundman2020 wrote:A true "Foley for film" stage DOES need to be isolated, to a very high level. Foley implies recording very quiet things, then increasing the level hugely to add it it the sound track. Even slight background noises become a thundering roar in the mix, if the room isn't isolated to very high levels. A Foley stage is about the toughest possible thing to isolate. You really need something like NR-15 or lower (roughly the same as NC-15).

003 is the computer lab we’d like to change to a mixing space. Approx 26.5 x 18 x 10.5

That's a MUCH better size for a control room! That would be ideal.

That's a problem, but not necessarily a big one. It can probably be moved. You'll need a structural engineer to take a look at that, and tell you what needs to be done to move that pole. It can be done: I have done it before, even for home studios. The cost doesn't have to be prohibitive either, but it absolutely must be done with the blessing and guidance of a qualified structural engineer.

Sounds expensive. Anything with "engineer" sounds expensive. I'm hoping I can figure a better layout that will remove the need to mess with the post.

Soundman2020 wrote:

004 Mixing space as you enter.

That needs fixing! If you plan to keep that room as a control room, then there are many issues with the current layout that would need to be dealt with, to make it usable.

I agree %100. I'm beginning to lean towards hitting the reset button. I think it might be cheaper in the long run and allow for a smarter room layout.

Soundman2020 wrote:

004 View through ceiling - the people who designed and installed this room didn't think a mixing space needed to have ceiling insulation.

They also didn't think that a control room needs any isolation at all! That open panel shows that there is NO isolation for this room, and no treatment either!

004 Recording booth door view

You said that this is a Foley stage, but I don't see any signs of that in the photo: Where are the pits? Was that photo taken when the room was NOT set up for Foley work? Pits taken out and stored somewhere?

004 Detail of pipe insulation. This is a heating pipe coming from the boiler room.

That's purely thermal insulation. No acoustic isolation at all. Pretty much all noises in that pipe will be heard in the room, and any loud noises generated in the room could also potentially flank through those pipes to other rooms.

Simple plan for construction

I'm trying to mentally correlate that drawing with the previous drawing, but not having much success! The two areas appear to be different shapes and sizes...

I've overlaid the two leaf construction for 003 in Yellow, and I've expanded the control room for 004 into what is currently dead space. (I don't know why it wasn't incorporated into the original design. Because we have a fairly useless cavity that is just some storage right now)

Soundman2020 wrote:I don't see that shown on the plan at all. Maybe you could highlight the inner and outer leaf for that room in different colors, to clarify the plan?

Sorry, I incorporated the entire two leaf construction into a solid yellow border. At the entrance wall for 003 you can see where I've peeled away the layers to show the construction. Not super clear, I do apologize for that.

Soundman2020 wrote:That room is waaaaaay too small to need diffusion or reflective treatment! It will need mostly absorption. Practically all absorption, in fact. I could run the numbers for you to be certain, but at a rough guess you are going to need absorptive treatment on well over 50% of the wall and ceiling surfaces. Diffusion is out of the question for that room: numerically-based diffusers can only be used successfully in rooms that are much larger than that. The lobing artifacts make it untenable for small rooms.

Good to know.

Soundman2020 wrote:

The drop ceiling will be removed in both 003 and 004 mixing and new drywall with isolation treatment will be hung from the original lath ceiling.

Why? I mean, removing the drop ceiling is most certainly necessary, but if there's another ceiling up there already, then adding a new one below it would likely create a 3-leaf system. Not a good idea, if you need isolation for low frequencies.

Well, when I say ceiling, it may be more of a bottom of the sub floor sort of affair - all mechanical are hung below it. This building is 100 years old, so I'd have to get up in the ceiling on a ladder to figure out exactly what its construction is (which I will do)

Soundman2020 wrote:This is where I'm confused about your isolation plan. A few paragraphs up you mentioned that 003 will get a proper two-leaf isolation wall, yet here you mention that in addition to that you think 004 will get a new wall! That doesn't make sense. A proper isolation system around 003 automatically implies modifying the wall to 004, which is adjacent! There's no other way of doing it.

My thinking was that each space needed it's own enclosed 2 leaf construction (including the ceiling, which is why I mentioned hanging from the original lath ceiling), but if you are saying that both control rooms can share a single two leaf wall then complete demo might be the smartest way to go.

Soundman2020 wrote:That's possible, yes. If you plan to do 5.1 in there, then the room needs to be designed from the start for 5.1 Trying to retrofit a 2.0 or 2.1 room for 5.1 is not something you want to do, but there's no problem at all in doing 2.0 or 2.1 in a room designed for 5.1, even if the 5.1 systems is not yet installed.

Good to know - I'll do some reading on 5.1 specifics and see if the larger of the two control rooms can be built to something resembling proper specs for 5.1 mixing.

Soundman2020 wrote:There seems to be a misunderstanding or misconception here, about how double-leaf construction works. You can't just install it where you feel like: if you want to isolate one room properly, using two-leaf isolation, then the entire room needs to be isolated that way: all four walls, and the ceiling, and possible the floor too. That implies taking the point of view of someone standing inside the finished room, and then confirming that there are ONLY two leaves between that person and ALL of the adjacent rooms: Not one leaf, not three leaves, or four, or any other number: there can be two leaves, only two leaves, and nothing but two leaves, in all directions. One of those leaves will be the drywall facing the person inside that room, and the other leaf will be drywall (or brick) facing the person in the adjacent room. Period. End of story. So if you work your way through this mentally, and you count more than two leaves in any direction, then you did something wrong: you don't have an isolation system.

So for example, if we are talking about going upwards from your room to the one above: you have the ceiling in your room, plus the existing ceiling above, plus the floor right above that. That is THREE leaves, so there's a problem right there. Something wrong. And if you were to put a two-leaf wall around 003 plus also a 2-leaf wall around 004, then you would have FOUR leaves between the rooms: that's very wrong. A three leaf system or a 4 leaf system will have a much higher fundamental resonant frequency that than a two leaf system of the same mass and total thickness. Always. And if the resonant frequency is higher, then the low frequency isolation is worse.

Again, I probably wasn't stating the thought clearly - my understandings was that the two control rooms would be isolated room within rooms, each with their own two leaf shell, one of which would connect to the ADR booth. Apologies for the muddling of intent, terminologies and logistics.

Soundman2020 wrote: That also isn't possible, if you want good isolation between rooms. There can be no holes at all in the leaves the define the rooms. You can allow just one single penetration to bring in the power feed, then all the wiring for the room must be done using surface-mount "trunking" systems. The electrician cannot, under any circumstances, cut holes in the drywall like he normally would to install boxes for outlets, switches, lights, etc. All of those can only be surface mounted.

I did know that much (I promise I have been reading!), but again, didn't clearly state it. I do need to add the electrical plan to the layout, but I'll do that after I have completed a final floor plan.

Soundman2020 wrote:

1. two leaf for each enclosed space?

Yes. That's the only way to get good isolation at low cost. But it isn't done as "two leaves for each room". Rather, it is done such that "between the interior of each room, and the interior of the next room, there are only ever two leaves, in any direction".

2. can the spaces share a two leaf wall?

It's not they the "can" do so. Rather, it is that they HAVE TO do so! There is no alternative, with correct two-leaf construction. So between your control room and your live room, you have drywall on the control room side, drywall on the live room side, and a gap between them. That's it: two leaves. The same applies in all other directions.

Clearly I misread the room in a room concept.

3. Is more air space between the two rooms helpful?

Most definitely! The equations for calculating the resonant frequency of a two-leaf system have only three major variables. One of those is the depth of the air cavity. The larger the cavity, then lower the frequency. The other two variables are the mass of each of the leaves, and how much damping (insulation) is in the cavity. Increasing any of those gives you a lower frequency, and better isolation. So more mass, more damping, and more depth are all good things.[/quote]

If there is something in the cavity, does this not count as an extra leaf? Should we be doing cinder blocks or something in the cavity between the control rooms?

Soundman2020 wrote:

Can this be done in phases effectively? (can we build 003 as a decently isolated space and revisit 002 at a later date?

Possibly, but not easily, and not cheaply. Unless you go with your own very next suggestion below...

*Is it cheaper/better to demo the whole thing and start over (keeping our low budget in mind)

Very likely, yes. In the demo, if you do it carefully, you can probably re-use a lot of the materials. Complete demo and re-build would allow you to build all of the walls as proper two-leaf MSM systems without trying to retrofit bits and pieces, and without being restricted by existing walls, doors, windows and other items. You would likely also not need to move that pillar, since you could re-design the rooms so that the pillar ends up inside one of the walls, in the cavity between the leaves. With a full demo, you'd also have good access to all the pipes, electrical and HVAC, as well as to the existing ceiling above, to deal with the issues associated with that. It would also make it a lot easier to figure out where your humidity problem is coming from, and to fix it properly: There are a lot of "pros" to this approach, and very few "cons".

Given the obvious inadequacy of the current control room I'm tending towards "scorched earth". Maybe I can throw a sound room destruction party for the students. Free pizza and hammers!

Soundman2020 wrote:

Layout (which items should I be aiming for? I've currently gone with #1 but I'm feeling like that's not the best):
1.Maximum air space
2.Golden Ratio
3.Angled walls

All of the above! And none of the above!

Why do I hear your answer being said in a Yoda voice?

Soundman2020 wrote:Sorry to be so cryptic, but studio design isn't about choosing one thing over another: it is about looking at all of the issues, getting the "big picture", then designating the best possible layout within that space, with as few compromises as possible. There will be compromises (there always are!), but there is no need to compromise any of the above. You can angle the walls that need it, at the best angles, and still have enough air space inside the walls to get the isolation you need, and also have a good room ratio. Those don't need to be traded off. There might be other trade-offs to get there, but these don't have to be.

Also, there is no such thing as a perfect "golden ratio" for a recording studio. That's a myth. In reality, there are many good ratios (a couple of dozen) that have be figured out be acousticians such as Sepmeyer, Louden, Bolt, Volkman, Bonello, and others. Each has its advantages and disadvantages, and each is suited to some studios better than to others: None of them is perfect, none of them is "golden", and none of them is better than any of the others for all situations. That's part of good studio design: choosing the ratio that makes the most sense for each project. Arguably, one could say that Sepmeyer's best ratio is preferably for most cases, but even then, that would not be accurate.

Yeah, I was looking at the Bolt distribution graph and puzzling over which area of the graph would best suit our space.

Soundman2020 wrote:

How much does a HVAC damper help to isolate sound?

Your picture does not show an HVAC damper. This is what HVAC dampers look like:

Your picture shows an HVAC silencer box, or baffle box, or muffler, but it is built incorrectly: the interior lining should only ever by done with proper duct liner, never with fluffy insulation. Over time the air flow will erode that, and you'll end up with fibers all over your studio...

I stand corrected yet again. Thanks!

Soundman2020 wrote:But to answer your question: A well designed and well built HVAC silencer can isolate sound VERY well. It uses several acoustic principles at once to do so, and the insertion loss can be quite high. However, the rest of the HVAC system needs to be designed in conjunction with the silencer: Even the best silencer in the world won't do much if the rest of the system is lousy: For example, if the flow velocity is too high, then the silencer won't achieve much since all of the noise will come from turbulent flow in the ducts and registers. And if the transition from duct to silencer and back again is not sudden enough, or does not involve a large enough difference in cross-section, then you won't get the necessary impedance mismatch, so you won't get good isolation, even of the silencer itself is well designed. HVAC is a system, and all of it has to be designed correctly.

I'm confident we can tune the flow to be whatever we need. Do you have any resources for how this transition would look? I'd like to build it into the plans, I think it's essential for the control rooms. We are supposed to meet certain health and safety standard, so it would be nice to actually do that.

Soundman2020 wrote:I'm downloading it now, and I'll take a look. If I see anything additional, I'll add another comment later.


- Stuart -

Thanks again Stuart, your response gave me a lot of information. I really appreciate it. I feel like our budget is tiny for what we are trying to achieve, but we always manage to get where we need to go, I hope this is no different.

Oh, if you are looking at the plans, there is a small power panel next to the hall door when you first walk in. You can peel off the 3D layers to see the 2D floor plan. I have not drawn it in properly in the 3D plan. I will update this promptly. It shouldn't impact the current layout, but I'm also going to play with a new layout from the destroy everything point of view, so it might be better to move it, so that wall can be sealed properly.

Funny story Stuart - I just stumbled on your chat with "T Elliot" regarding the artist run centre - I know Tom and I know the space (which is now built). I'm reading through that thread now and there is a tone of great stuff. I'll chat with Tom directly as well and see how they approached certain things.

Just thought I'd share!

Cheers,
Nathan

Some more upper ceiling images:
It appears to be heavy plaster attached to wooden lath, and it's crumbling but good. Removing drop ceiling tiles is like playing Russian roulette with nasty dust/plaster chunks.

Any more progress on this? I'm dying to see how it turns out!


- Stuart -

Hey Stuart,

Thanks for checking in! Construction is underway. Because of budget constraints, we had to go with the single room, and will fix the other space in the future. We sealed and varpourbarriered the wall. (as much as we were able to expose without tearing down the other room) The old windows were removed and filled in with solid material and insulation.
This is what is being built (only the space on the right hand side). We lucked out and the original drawing was incorrect - the post is actually outside the walls of the room. There is still the problem with the water pipe which runs through everything, so I had a bulkhead built around it to keep it outside the envelope of the room.

Here are the inprogress pics:
Here you can see the view from the hall. The entrance to the old control room is to the right. Luckily there was space to access the door, and it didn't need to be moved.
This is the reverse shot of the room. The small bulkhead there is some electrical conduit which would have been too expensive to move. Again, we are building the doulble layer of drywall around it, to keep the evelope of the room as tight as possible.
This is the bulkhead I spoke about
Another view of the bulkhead.

So like I said, construction is underway, first layer of drywall is hung on resilient channel. Next layer of drywall will be hung with GreenGlue. Electric will all be surface mounted. Sprinkler guys are just finishing their job and then the ceiling will be hung. We aren't using resiliant channel there, going right on the hat channel, then second drywall with greenglue. There was concern about the structural integrity of the resiliant hanging from the hat channel vertically, and we didn't have the budget to build a timber structure.

There is no budget currently for AC in the space, which is definitely needed. I'm looking into possibilities there.

I would love your input on how we can proceed to finish the interior. I was thinking a room kit from Auralex to start with. Maybe a skyline diffuser and a couch at the back. Feedback welcome!