Soundman2020 - Studio Design Forum

Hi all. Long post warning. I tried my utmost to give as much information as possible and go by all of the posting guidelines. I also put subtitle categories in if you want to skip ahead. Here we go...


Background:
I am a musician, electronics tech, technical director and freelance sound engineer. I have been researching this and other forums for years. I have read Built It Like The Pros by Rod Gervais as well as other books. I have a working understanding of the principals involved in MSM assemblies to achieve isolation; therefore, I know my goal below will be difficult and expensive.

Overview:
I have small music room on the second floor of an attached garage with a cathedral ceiling. It is adjacent to the master bedroom and adjacent to a partially finished workshop at the rear. The music room faces a busy street 39' in front, and faces two large apartment complexes 108' in front, across the street. The house is under a flight path, and has a railroad track approx. 600' behind the back yard. The approximate Dimensions: of the room are: Floor area 270.5"x182.5", knee wall height is 31.5", and the subfloor to bottom of central support beam 117.5"

Use of the space:
1. The space is used primarily for writing, tracking and mixing, all in the same room. I play and record acoustic drums, electric guitar and bass as well as keys and synth. I will sometimes put amps in the rear workshop when tracking guitar and bass.
2. I use the space for mixing music recorded in other larger, better sounding rooms.
3. The room has been used to record voice over successfully but with some difficulty.
4. The room had also been used as a rehearsal space for rock bands, but due to the proximity to neighbours, has caused issues and I now rehearse elsewhere.

My goal:
To achieve the best possible isolation from external noise, and to have the noise that I make blend in with the outdoor ambiance to not bother neighbours. Isolation between the music room and other parts of the house is not the goal; however, I know I will need to address all partitions above, around and below the music room to get any meaningful results.

Specific to my uses: For use 1, 2, 3 the most offending is traffic noise from large trucks, Harley motorcycles, and vehicles with loud exhausts. Only the occasional yet extremely loud Fedex Freighter airplanes, require pausing or retakes of louder sources like drums and amps. For use 3, quiet voice over and vocal recording, sometime even a neighbour's dog barking can affect a take.

For use 4: The biggest issue with full bands of course is the low frequency content from drums and electric bass being much louder then the outside ambience. If it is determined that enough broadband isolation can be achieved within budget and structural limitations to allow me to resume rehearsal in my room, that is a bonus. If not, I can continue rehearsals elsewhere. If the level of isolation for full band practice can not be achieved, it is still worth it for me to address the problem for uses 1, 2 and 3, as it is difficult to work exclusively during low traffic hours, noise bylaws taking effect in the evening.

Budget:
My budget is $15k-$20k cad including HVAC. This does not include studio equipment nor acoustic treatment.

Consultation: I am now consulting with an architect who specializes in acoustics, and am reaching out to structural engineerings to determine my existing live, dead, and point load capacities, and determine options for beefing up the structure to support the extra mass that will be needed. I intend on doing most of the work myself to keep labour costs at a minimum.

Noise Measurements:
Measurements were done with a Galaxie Audio CM130 SPL meter on C weight and slow. This first series of tests (A) represent use 1 where I would be tracking drums:

Test A1 - Drums: Outside, night, no traffic. Lowest outdoor ambiance was 47dbc. Loudest measured drums 73dbc.
Test A2 - Drums: Garage, daytime, low traffic. Lowest garage ambiance was 40dbc. Loudest measured drums 80dbc.
Test A3 - Drums: Studio, daytime, low traffic. Lowest studio ambiance was 39.5dbc. Loudest measured drums 111dbc.

I think this shows the absolute minimum amount of transmission loss I need, but there are two more tests I want to do now that I have a baseline of quiet ambiences in three locations: (B) Same test as (A) with a full rock band, and (C) measure the worst case scenario outside noise during peak traffic hours (motorcycles, train, flights, etc.) With the COVID-19 lockdown measures I will need to wait a while before I can do tests (B) and (C).

Existing Construction Details
Please find a download link to a comprehensive, as built, to scale Sketchup file detailing the existing structure with the different structural elements in separate layers:

Sketchup File: https://drive.google.com/open?id=1ALMR0NUflN9YwCaPJuCCUGDiy4rPVke6

To summarize the existing construction:

-1st and 2nd floor walls are 2x4 wood frame, with R12 fibre glass batts, outside wall sheathing is 1/2" OSB, cladding is vinyl siding.
-The 2nd floor rests on wooden webbed trusses, 16" OC with a 16" high truss depth, and a span of approx. 270-1/2".
-The 2nd floor deck is OSB, appears to be 5/8", I could not confirm thickness at the time of writing this post.
-The under side of the 2nd floor deck is spray foamed. I'm not sure what kind of spray foam, density, open or closed cell, etc.
-The music room currently has 3/4" hardwood floor atop the OSB subfloor.
-Roof sheathing is 3/4" OSB and rests on wooden trusses with metal webbing, they are 24" OC with a 16" high truss depth.
-The roof is vented at the soffits and at the ridge, and the spaces between trusses are filled with approx. 14" thick fibre glass batts.
-The only heat source in the music room is a vented natural gas fireplace insert which vents through the roof.
-A Skylight is installed in the workshop and a stair case may eventually be installed descending into the garage from the workshop.


Here are some 2d renders from the Sketchup file:



Outdoor Pictures:



Indoor Pictures:






Working towards a design
In addition to professional consultation, I am seeking advice and criticism here to help me come up with a design. My approach will be to primarily use the techniques outlined in Rod Gervais' book, prepare some drafts, get some feedback, start costing things out, and hopefully, many revisions later, end up with a workable design. Below are some of the elements that would go into the first draft. None of this is set in stone... If I say some silly things and present uninformed assumptions, please point it out.


The specifics
1. Walls: I will add mass to the outer wall between the existing 2x4 studs with at least two layers of 5/8" drywall and Green Glue such as: OSB > GG > DW > GG > DW > R12 FG. I have looked at airspace and stud depths for the inner wall using Gregwor & Audiomutt's MSM TL Calculator, but I haven't decided if a 2x6 24"o/c inner wall will be worth the extra materials cost and loss of footprint. The inner wall would be: FG batts > vapour barrier > structural OSB sheathing > GG > DW > GG > DW

2. Windows: The two front facing windows already need to be replaced as the seals are completely shot, and my wife says the windows must remain. I don't need egress so I will opt for a units that don't open. A local supplier is able to build exterior windows according to the specs in this pdf: https://www.viracon.com/pdf/ViraconAcousticPerfDataTables.pdf.
So I am thinking that a double glazed insulated unit with two laminated panes of different thickness, with the largest possible air cavity between the panes is the way to go for the outer leaf.

For the interior leaf, I'm considering a single massive laminated pane in a custom frame, with desiccant in the air space, like the one described here: https://www.gearslutz.com/board/studio-building-acoustics/1272121-how-soundproof-weather-seal-exterior-studio-window.html

3. Doors: I will be using the Super Door design in Fig. 5.6 in Rod Gervais' book for the entrance to the studio and for the adjacent workshop.

4. Ceiling: The approach for the ceiling is what is described in Fig. 10.23 and 10.22 in Rod's book, but with the addition of Green Glue (2 or 3 tubes worth per 4'x8') in between all layers of DW and sheathing.
I will also add a layer of structural sheathing to the underside of the existing roof trusses to add mass and to have a continuous substrate to screw the DW sheets into.
To increase the height of a new inner ceiling, the existing 2x6 joists on the sides of the central beam would be removed. I may be left with space at the apex that can be used for bass traps.
5. Floor: The approach for the floor would include techniques described in Fig. 10.16 and 10.19 in Rod's book.
I can only add mass form above due to spray foam on the underside of the OSB. I have read the thread describing why floating a floor is probably a bad idea. If I can avoid doing that and still get "some" amount of TL the project could still be worth doing. The math needs to be done to determine how much "some TL" actually is. I understand what is involved in calculating TL for MSM assemblies, but I'm not sure how to approach it for an undamped floor (that is not sitting on a concrete slab) beyond what Mass Law says about +6db of TL each time the mass doubles.

If I don't completely float a new floor assembly and go for a decoupled solution as in figures 10.16 and 10.19, my thinking is to add as much Gypcrete mass as possible, replace the two layers of 1/2" plywood with two layers of 3/4" MDF, and apply 2-3 tubes worth of Green Glue (per 4'x8' area) between all solid faces. The entire studio floor would essentially resemble the Glenn Drum Riser design sitting on top of Gypcrete.Its still not 100% clear to me how effective these decoupling methods are for airborne versus impact sound...

It also is worth noting that the previous owner had a woodworking shop and machinery above the garage before it was renovated as it is now. He tells me the floor was rated for 90psf, but did not specify if this was live or dead load, so I'm taking this with a grain of salt. In any case my engineer will investigate this.

6. HVAC - This is the next area I need to research. For budget reasons I'd like to keep the fireplace, but the roof vent needs addressing. I will talk to natural gas installers to see what code allows for moving the vent away from the street. If it can't be done, I'll likely need to go with a mini split. Ventilation, HRV/ERV, and silencer boxes also need to be researched. I'm hoping this stuff can be installed in the storage mezzanines in the workshop, above the walk in closet.

7. Electrical. I do not plan any changes to the existing electrical at this time.

8. Acoustic Treatment The only thing I am considering adding at this time is bass traps at the knee walls and ceiling apex The geometry of these spaces make them hard to utilize for anything else. Maybe integrate nice wooden shelf top into the design of the knee wall bass traps...


Questions

1. Wall Questions:
1.1 - How do I calculate the thermal properties of an MSM wall assembly? Is it as simple as adding the R values of inner + outer wall batts?
1. 2 - It has been shown that fluffy batt insulation has a better cost-benefit ratio than mineral wool in MSM assemblies. Since I am not on a concrete substrate, would I get more benefit form denser mineral fibre in my walls and ceilings? Would this increase the overall damping effect?
1.3 - If I go with 2x4 inner wall framing, would 24" o/c spacing for the knee walls and front and rear walls further lower the MSM resonant frequency?

2. Windows Questions:
2.1 - Are there any other considerations for my exterior windows that could further increase TL given the obligatory 3 glass leaves?
2.2 - Would it be best to go with a vinyl frame or aluminum frame given the choice?
2.3 - Is it best to compensate for the limited surface density of the outer two pane window by increasing the density of the inner single pane window?
2.4 - Would it be best to insulate between the window frame and jamb with mineral wool versus expanding spray foam?

3. Ceiling Questions:
3.1 - Would it be a good idea to try to seal the metal the webbing of the roof trusses in to try to keep the airflow from the soffit above the FG batts?
3.2 - Regarding the use of resilient clips: On P.274 of Built it Like The Pros Rod writes "There are things however that you can do to maximize isolation in these cases (Attics and Other Rooms Inside Your Home), even if you can't build a room within a room. To begin, this would be a case where I would strongly advocate the use of isolation clips." Is Rod advocating the use of isolation clips in addition to MSM construction or only in cases where you can not build a room in a room?

4. Floor Questions
4.1 What is the best mathematical approach for my type of "drum head" floor? I assume its resonant frequency first needs to be calculated, then find the right amount of mass that will lower the resonant frequency below the audible range?
4.2 Are the decoupled floors in figures 10.19 and 10.16 effective against airborne sound? Are they only effective for impact sound?
4.3 In those decoupled systems, is the space occupied by the OC703 considered an airspace in an MSM assembly where the outer leaf would is the underlayment and the inner leaf is the plywood (or MDF) above it? I know there is technically no air gap, but the OC703 is porous to air. If it can be seen as an airspace, would two layers of OC703 increase damping?

Ouff, that was a lot...

Huge thanks to everyone who read parts or all of this post.

Wow! What a great initial post for a studio project! An excellent example, that hopefully others will follow.

I'm a bit tied up right now trying to meet a deadline for a client, so I can't comment immediately, but I did want to let you know that I did see your post, and I'm impressed with your thoroughness. I'll answer more completely in a day or so.


- Stuart -

Soundman2020 wrote:Source of the post Wow! What a great initial post for a studio project! An excellent example, that hopefully others will follow.

Thanks, a lot of time went into this post.

My structural engineer just did a site visit so I should have some load bearing numbers shortly.

DARN DARN DARN!

I just found this again, and realized that I never replied, like I said I would.

Hopefully, this isn't too late to be useful....

I have small music room on the second floor of an attached garage with a cathedral ceiling. It is adjacent to the master bedroom and adjacent to a partially finished workshop at the rear. The music room faces a busy street 39' in front, and faces two large apartment complexes 108' in front, across the street. The house is under a flight path, and has a railroad track approx. 600' behind the back yard.

Wow! You sure do know how to pick a complicated set of circumstances! All of those are factors that indicate a need for high isolation... but the "second floor of an attached garage" isn't such a good platform for doing that...

. I play and record acoustic drums, electric guitar and bass as well as keys and synth. I will sometimes put amps in the rear workshop when tracking guitar and bass.

Drums and bass are two loud, instruments, with plenty of low end... which isn't easy to isolate... I'm sure you already know all this, but worth mentioning for others following your thread...

the most offending is traffic noise from large trucks, Harley motorcycles, and vehicles with loud exhausts.

I'd suggest measuring the spectrum of those sounds, to find out what you are dealing with, in terms of frequencies.

My budget is $15k-$20k cad including HVAC. This does not include studio equipment nor acoustic treatment.

Tight, but maybe do-able... depending on how much isolation you are willing to settle for.

Here are some 2d renders from the Sketchup file:

Nice SketchUp work!

Working towards a design

Before getting into that, it would be best to come up with a number that represents how much isolation you need, in decibels. It's a lot easier to design an isolation system, when you have a goal to design for.

I have looked at airspace and stud depths for the inner wall using Gregwor & Audiomutt's MSM TL Calculator,

I wouldn't put too much trust into that calculator... there are some flaws with it, and it is too simplistic. I've seen some predictions from that, that don't make a lot of sense. Yes, it seems to use the correct equations (I posted those for Greg quite a while ago), but the implementation seems ... strange.

but I haven't decided if a 2x6 24"o/c inner wall will be worth the extra materials cost and loss of footprint.

You don't need 2x6 for that: 2x4 would be fine. But what you do need, is to get the correct air cavity depth between the leaves, to achieve your desired MSM resonant frequency.

A local supplier is able to build exterior windows according to the specs in this pdf:

I get a "404 not found" with that link. IT looks like they change their website, or eliminated that product?

So I am thinking that a double glazed insulated unit with two laminated panes of different thickness, with the largest possible air cavity between the panes is the way to go for the outer leaf.

An IGU in the outer leaf plus a single pane in the inner leaf, creates a 3-leaf system, with all the potential issues that could bring. You'd need to do the calculations to ensure that your f+ and f- will both be low enough, and your mass high enough, to achieve your isolation goal.

For the interior leaf, I'm considering a single massive laminated pane in a custom frame, with desiccant in the air space, like the one described here:

3. Doors: I will be using the Super Door design in Fig. 5.6 in Rod Gervais' book for the entrance to the studio and for the adjacent workshop.

That's a huge amount of mass for an upper floor. Have you seen this thread? site built door for high isolation

I will also add a layer of structural sheathing to the underside of the existing roof trusses to add mass and to have a continuous substrate to screw the DW sheets into.

So you are going with a 3-leaf ceiling... which is fine, because you have no choice, due to the vented roof deck.

To increase the height of a new inner ceiling, the existing 2x6 joists on the sides of the central beam would be removed

NOPE! Nope! NOPE! Those are raised collar ties! Those are structural, and part of the roof truss system. don't touch those!!! They are holding your roof together...

The approach for the floor would include techniques described in Fig.

Once again... before deciding how to do your floor, you should first identify how much isolation you need, in decibels.

If I can avoid doing that and still get "some" amount of TL the project could still be worth doing.

You can get "some", yes, but the question here is: will that "some" be "enough"? If it works out to be less than your target isolation number, then you have a problem... But if it is higher than your target isolation number, then you are OK!

Its still not 100% clear to me how effective these decoupling methods are for airborne versus impact sound...

For impact sound: pretty good. For airborne sound: not so much. Take a look at Jennifer's thread on how she built those drum risers in her studio, and the results she got.

6. HVAC - This is the next area I need to research. For budget reasons I'd like to keep the fireplace, but the roof vent needs addressing.

That chimney is a major issue: it's a huge hole through all of your isolation system. You would need to figure out how build some non-flammable silencers (something like a car exhaust muffler), that still provides the required draft for the fireplace, and how to decouple them.

If it can't be done, I'll likely need to go with a mini split.

That would be my suggestion.

Ventilation, HRV/ERV, and silencer boxes also need to be researched. I'm hoping this stuff can be installed in the storage mezzanines in the workshop, above the walk in closet.

You might find this thread useful. You already know most of what is in there, but some things are pertinent, I think. why your studio needs proper HVAC.

7. Electrical. I do not plan any changes to the existing electrical at this time.

When will you do that planning then? You can't leave it too long, as the electrical system isolation is a rather important part of the studio build. I assume that at present there are some lights and outlets in the attic, so you will need to figure out how to remove those, and bring in just one power feed through the inner-leaf, then re-distribute that around the room, using surface-mounted raceway systems. You will likely also need to do the same with other cables, such as the audio/video/computer wiring going to your recording rooms, as well as phone, internet, cable TV, alarm, CCTV security system, intercom, etc. All of those require penetrations through your isolation leaves, so you should be planning for those now.

8. Acoustic Treatment The only thing I am considering adding at this time is bass traps at the knee walls and ceiling apex The geometry of these spaces make them hard to utilize for anything else. Maybe integrate nice wooden shelf top into the design of the knee wall bass traps...

Your room is going to need a lot more than just that. With the strange shapes and small size, treatment is going to be extensive.

1.1 - How do I calculate the thermal properties of an MSM wall assembly? Is it as simple as adding the R values of inner + outer wall batts?

1. 2 - It has been shown that fluffy batt insulation has a better cost-benefit ratio than mineral wool in MSM assemblies. Since I am not on a concrete substrate, would I get more benefit form denser mineral fibre in my walls and ceilings? Would this increase the overall damping effect?

Higher density usually means poorer isolation in low frequencies. Go with the lowest density. Usually, pink fluffy is just fine for that, but if you want better fire rating then you could go with a low density mineral insulation.

1.3 - If I go with 2x4 inner wall framing, would 24" o/c spacing for the knee walls and front and rear walls further lower the MSM resonant frequency?

There is a slight advantage to 24" OC over 16" OC, yes. You can probably find a lot of the answers you need about MSM in the rather old but rather good "Wyle Report". It's a fascinating read, and very useful for understanding MSM (alright they do use different terminology ...) It's in the reference library: Document Library First one on the list.

2.1 - Are there any other considerations for my exterior windows that could further increase TL given the obligatory 3 glass leaves?

Normally, you need the most mass on the middle-leaf of a 3-leaf system (see the Wyle report to understand why...), but that won't be an option if you use an IGU. So what you would need then is to increase the mass as much as is needed on ALL of the leaves, such that your f+ and f- are both low enough, and your mass is higher enough, to achieve your target isolation number. Increasing the cavity depth between the IGU and the inner-leaf pane is also important.

2.2 - Would it be best to go with a vinyl frame or aluminum frame given the choice?

There's not much in it. Aluminium has higher mass, of course, but vinyl has better damping. Most window frames have multiple interior parts and plenty of mass anyway, even with vinyl, so it's likely not an issue. Personally, I prefer vinyl: I think it has a slight advantage.

2.3 - Is it best to compensate for the limited surface density of the outer two pane window by increasing the density of the inner single pane window?

Yes, but like I said above, in reality it is the MIDDLE leaf of a 3-laf system that should have the most mass. In fact, it should have as much mass as the other two leaves combined (ie, M2 = m1+m3). That's the optimum layout for a 3-leaf system. Since you don't have that option, the second best is to increase the mass of all three panes.

2.4 - Would it be best to insulate between the window frame and jamb with mineral wool versus expanding spray foam?

Definitely! Spray foam is very often closed-cell, and therefore has lousy acoustic properties. It also dries hard and rigid, this creating flanking paths. However, if you need a good seal around the edges, you can use spray foam to help with that.... and then use abundant caulk around the joints to add mass and improve the seal even more.

3.1 - Would it be a good idea to try to seal the metal the webbing of the roof trusses in to try to keep the airflow from the soffit above the FG batts?

I'm not sure I understand the question. Maybe you cold re-phrase, or draw a diagram to show what you mean?

3.2 - Regarding the use of resilient clips: On P.274 of Built it Like The Pros Rod writes "There are things however that you can do to maximize isolation in these cases (Attics and Other Rooms Inside Your Home), even if you can't build a room within a room. To begin, this would be a case where I would strongly advocate the use of isolation clips." Is Rod advocating the use of isolation clips in addition to MSM construction or only in cases where you can not build a room in a room?

No. He specifically mentioned: "if you can't build a room within a room", so that clarifies that he's talking about when you are not able do to a proper fully-decoupled two-leaf MSM system, for whatever reason: second best is to go with clips and hat channel on the existing studs and joists.

4.1 What is the best mathematical approach for my type of "drum head" floor? I assume its resonant frequency first needs to be calculated, then find the right amount of mass that will lower the resonant frequency below the audible range?

You would need to know the resilient properties of the insulation you plan to use. Specifically, you need to know the spring constant for that material, then use the normal equations to figure out the resonant frequency, and the isolation. However, you do have to take into account that with this system, you also have the air spring, in parallel to the fiber spring, so you need to take that into account as well. And since they are in parallel, just like two parallel capacitors in an electronic circuit, the result is HIGHER, not lower... thus, your resonant frequency will be higher than either the fiber spring or the air spring by itself, and the isolation will be lower (worse).

4.2 Are the decoupled floors in figures 10.19 and 10.16 effective against airborne sound?

Not so much... They do offer some isolation, yes, but not as good as a properly floated floor.

4.3 In those decoupled systems, is the space occupied by the OC703 considered an airspace in an MSM assembly where the outer leaf would is the underlayment and the inner leaf is the plywood (or MDF) above it? I know there is technically no air gap, but the OC703 is porous to air. If it can be seen as an airspace, would two layers of OC703 increase damping?

"air space" is a bit of a misnomer here. Rather think of "cavity depth". What matters for all MSM calculations, is the distance across the cavity, from the inner-leaf surface to the outer-leaf surface, regardless of whether or not there is insulation in there. That's the distance you use in the equations. Insulation is mostly air anyway, so you just ignore its presence for the distance.

In addition to that, the insulation does several things to IMPROVE isolation: it changes the way air deals with heat, from adiabatic to isothermal, which improves efficiency. It reduces the speed of sound. It makes the cavity seem LARGER than it is, from the point of view of a sound wave trying to get across. And it damps the multiple resonances going on inside that cavity otherwise, which would rob you of isolation if they were allowed to be there. All in all, the insulation improves isolation by as much as 16 dB, under some circumstances, as compared to an empty cavity. It is very necessary, and is taken into account in the MSM equations in the constant that you use: there is one constant for an empty cavity, and a different constant for a filled cavity.

Ouff, that was a lot...

Yup!

And as I said at the start: hopefully this reply comes at at time where it is still useful for you...

- Stuart -

Hey everyone! So I started really focussing on this room about a year ago during the covid shut down. Professional and family commitments meant that I had to completely step away from this, but I figured I would update a few things as I keep working on a design so here is a long overdue update.

First, Soundman, thank you for taking the time to address my first post point by point. Never too late to be useful. Despite the complicated set of circumstances, I am undeterred, but now realize my budget is most likely going to be well north of 20K... Hobbies are expensive... At least I'm not into collecting classic cars...

Regarding coming up with a decibel number that represents how much isolation I need, I still have some more measurements to take and math to do. But rather than coming up with a theoretical number based on those measurements, I really think this is a case of having to deal with the structural limitations of the existing building.

Structure: I have hired a mechanical engineer to evaluate the floor and ceiling assemblies and that shows that I can add an un-factored dead load of 30psf to the top chords of the floor trusses. It also shows that I can add an un-factored dead load of 18psf to the bottom chords of the roof trusses. In my first post I eluded to the fact that I was not entirely sure about how to work the math out for the floor assembly. I'm also not too sure about the math for the obligatory 3 leaf system at the roof. I'm going to need help working that out, but I am now thinking that working out a theoretical isolation number based on these maximum dead loads is the best way to go since I know I can not exceed them. I have more research to do on equations etc and will post about that separately.

Glass: As for the local supplier I found that was able to build exterior windows to a certain spec, well it turns out they could only supply the panes of glass. They were not able to build the frames. Found that out while working on another project... Regardless of that, I have attached the PDF from STC Viracon. Just note that these specs do not denote any details about the frames, only glass type, thickness and air gap.



Given what I know about local glass suppliers and window frame construction. I am now thinking to avoid the 3 leaf problem here and use a single pane for my outer leaf and a single pane for my inner leaf, sealed, with dessiccant etc. However; I still need to figure out or find a supplier that can build at least the exterior frame. Not sure that I will be able to DIY something that will deal with Canadien weather.

Doors: I was able to source 4 inexpensive used solid core doors so that's a little win. I have seen and read the "Site Built Door for High Isolation" thread that you referred to. Was there something specific I should look at again in that thread? I suppose I can always consult with my engineer about weather point loads will be problematic when my door design is completed. I was going to opt with a design with dual trunk rubber gaskets on the bottom as well, as opposed to drop seals.

Roof: My engineer confirms I can remove the collar ties without issue.

HVAC The natural gas fireplace is now gone and the vent will be removed, and sheathing patched up. I will opt for a mini split for heating and cooling. Definitely still need to look closely at HRV/ERVs...

Electrical All comments noted, thanks.

Treatment I am now intimately familiar with the cost of and methods involved in DIY acoustic treatment. More on that in possibly another thread.

Math I will have to dig into the Wyle Report to help me figure out the math for theoretical dB limits of my roof and ceiling assemblies. I guess I also have more learning to do about spring constants for the type of floor assemblies I am looking at.

A few more things:

The engineer that did the structural evaluation also designed a stair case leading to and from that garage in what was the workshop area. My contractor is looking at those stairs this week. Given code requirements for these stairs, I'm now looking at how to best use the remaining floor space in the workshop area. One option would be to move the wall between the workshop and studio back to allow just enough space for the code required landing at the top of the stairs. This would give me a bit more space at the drum corner.

Below is a 2d export showing a few things:

1. Potential new location of the non load bearing wall between the workshop and studio.
2. Approximate location of the new inner walls.
3. Swing direction of two super doors.
3. Location of machine room for HRV/ERV, mini split blower and drain pump.
4. Approximate mix position (MP).

One thing I would like input on is weather having the MP here with the vaulted ceiling rising above my left and right sides would be better then having the MP along the long axis of the room. If this was a rectangular room I would not place it here. Just wondering what how the vaulted ceiling might affect the choice of MP. I'm thinking FRP at the sides might be a little easier to treat as some of the reflections will be reflected downwards.

I welcome any and all comments and questions.
Thanks.

Glad to hear that things are coming along.

Just in case you are left wondering how long it may take Stuart (Soundman2020) to reply, please be aware that he has been silent on all fora for the last 4 months. We just heard why:

Dr Space wrote:Source of the post I got a long mail from Stuart the other day. He will return soon. He has been ill. He is sorry.
Ricardo,, Dr Space.. :D

If you need to hire a pro for some advice, consider avare (real name Andre) as he is in Hamilton Ontario, and will appreciate what to do so that it deals with Canadian weather and what to do with your roof and all the rest.

Your news sounds good with a few hiccups along the way. With regard to going over budget, it is so common in DIY studios that I am not surprised.

Elusive Sounds wrote:Source of the post I figured I would update a few things as I keep working on a design so here is a long overdue update.

Glad to hear it is still moving forward! From your last post, it seems you have advanced quite a bit on all fronts Do you have any further updates? I'm kind of intrigued with your project!

- Stuart -

Work / life update. Right around late November 2020 a cultural centre and performance venue where I am technical director received a sizeable grant to build a 5.1 post production audio and video post production and live control room. So since December 2020 I have been very busy crash designing and then building a new room in a 100+ year old heritage building... Lots of budget, little time and it turned out really great. One of these days I will post a photo journal of this build. Oh, and not to mention a brand new Stagelam floor (90 sheets worth) as well as a 22' perforated motorized projection surface in the main performance space. Very busy!... Anyway here are a few pictures of that build. Sorry about the 90deg rotation, I dont know how to fix that. The source files are not 90 deg rotated.






On the life side of things my wife and I got married (don't recommend Covid weddings lol) in October 2020 after being together 13 years or so. And as I am typing this I am sitting next to her while she is holding our brand new baby boy born two days ago.

How life can throw you curve balls!

The build looks great, those grey panels look well chunky. I look forward to your photos of the build.

And congratulations on your marriage and new baby boy!

Cheers!
Jennifer

I will be dedicating some time after the holidays towards working on this. Hoping to hear some comments on the mix position. Wondering if having the LR speakers at against the vaulted ceiling (firing length wise) or at the windows (as pictured above), firing width wise, would be best. Not sure how the vaulted ceiling affects things.

To elaborate a bit on my previous question. Where should the mix position be given my vaulted ceilings? I know for small rectangle rooms the default is to fire along the long walls (position A), but would I benefit from the added ceiling height at mix position B? Would the first reflection points on the vaulted walls be less problematic to treat as reflections would be reflected downwards?

Its approx. 115" from floor to existing ceiling. Other dimensions noted previously.

Thanks,

That's actually a tough call! I can see your dilemma.

A couple of quick questions. (The info is probably in some of your previous posts, or the SketchUp model, but I'm short on time to g hunting for that): What is the length and width of the room, and what is the height of the ceiling where it meets the knee walls? I'm thinking this might be one of those cases where having the speakers firing across the room, rather than down the length of the room, might be the better option, but the dimensions of the room would help to decide...


- Stuart -

Soundman2020 wrote:That's actually a tough call! I can see your dilemma.

A couple of quick questions. (The info is probably in some of your previous posts, or the SketchUp model, but I'm short on time to g hunting for that): What is the length and width of the room, and what is the height of the ceiling where it meets the knee walls? I'm thinking this might be one of those cases where having the speakers firing across the room, rather than down the length of the room, might be the better option, but the dimensions of the room would help to decide...


- Stuart -

Floor area 270.5"x182.5", knee wall height is 31.5", and the subfloor to bottom of central support beam is 117.5". Of course that is not considering new inner walls and ceiling assemblies.

Based on that, I would think that "position B" might be your best bet. The reasoning goes like this:

- The floor area is large, and so is the room volume: that gives you some "wiggle room" with the acoustics
- You can likely still get a 20ms delay (or nearly 20m) for the first reflections for the rear wall. (With over 15 feet from front wall to rear wall, and assuming the mix position to be maybe 5 feet or so from the front wall, that gives you 10 feet + 10 feet for the reflections, and since sound travels at roughly 1 foot per ms, that gives you roughly 20 ms(rules of thumb).
- The ceiling panels are angled steeply. It would likely not be easy to deal with that if you had the mix position set up at "A".
- For the same reason, it would be tough to do serious bass trapping on that rear wall with mix position "A". Not impossible: just hard.
- Ditto for flush-mounting your speakers: Building soffits against a steeply angled "wall" ain't easy.
- Same subject: building soffits with mix position "B" is fairly straight-forward.
- With mix pos "A", the door on the right wall seems to be roughly at the first reflection point, which might be problematic.
- The door in the rear corner, is in the rear corner for both options! So that's an issue, but it doesn't affect the decision, since it's an issue in both cases! That said, with "B", the room is wide with plenty of space for bass trapping across most of the rear wall: with "A", I already mentioned the difficulty if treating that. So here, to "B" wins out.

Overall, I think "B" would be your best option.

- Stuart -

either position would work given you're probably going to want to use the peak to create a large absorber and with some hard surfaces can provide the desired symmetry either direction. the disadvantage of the long approach is that door on your right (when facing the speakers) because if you like to have instruments and gear on either side, the door can be a hinderance.