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Building a new Drum Room

Hi!

I have been slowly working on building out a new room in my basement for practicing/recording drums.
It's been a slow process, that has thus far involved removing water heaters, and breaking up the concrete floor to re-route the water main so that I have a relatively unobstructed floor space to work with.
I have about 8' 4" from floor to the bottom of the ceiling joists, and about 11 1/2' x 14' of space to work with.

As a side note, the rest of the basement is finished, and the lovely wife isn't wild about me tearing that stuff apart as I do my build.

I have started beefing up the existing subfloor above my space using 'rods method' of adding two layers of 5/8 drywall between the joists, with green glue, and then battening them into place with 1x2.

My plan is to build the 'room in a room' and have a new "inner ceiling" supported by the new framing I build.
In the picture attached you can see what I have going on thus far.
My questions are:

In the attached picture, you can see a space (labeled A). On the other side of that is the brick veneer of my home.
If I seal that area up with drywall and acoustic sealant, am I essentially creating a small 3-leaf system once I have my drum rooms walls built? Should I fill that cavity with layers of drywall? just insulation? Or is it such a small space that I shouldn't be fretting about three leaves?

Also, Above this ceiling is our 'formal' dining room (not used much).
In the space labeled "B" you can see the ductwork feeding the vents in that dining room.
Keeping in mind that I AM going to be building that decoupled "inner" ceiling, what should I do about that duct and vent feeding the dining room?
Attached files

Comments

Jason Morris Tue, 03/20/2018 - 07:32
I went ahead and attached a couple of the old sketches I did for my room.
At the time I did these, I was planning on an "inside-out" wall. After reading Rods book, I am wondering if I should should just build the walls an inch away from the existing concrete walls. I think it might be simpler and easier to seal up.

As I mentioned above, that box in the upper right is no longer part of the plan, as I move the water main around the corner.
The grey walls are concrete. To the left of my room is the garage, with the far left door leading to a flight of stairs going up to the garage.

As I said, I will try to update my sketch and add more detail this week.

Thanks again.
Attached files

Jason Morris Mon, 07/15/2019 - 11:07
So, i did what you (brilliantly) suggested and used the RTA app on my iphone, which is part of AudioTools...

it looks like my problem frequency is actually 32hz. Thats what I am hearing in the drum room.
and my AC unit is also crazy loud.

Im uploading a couple screenshots from my iphone.
One is taken right next to the AC unit.
Another from inside the house on the other side of the AC unit, and a third from inside the studio.

In the last pic (studio)You will see something at 125 and 250 registering. that is hand noise from me fumbling around taking the screenshot.
When im just holding it only 32 and 60 are registering at all.
Attached files

kmetal Mon, 07/15/2019 - 12:06
Jason Morris, post: 461492, member: 51197 wrote: It is fully enclosed, but its hard to describe how we did it. But being a glutton for punishment, I will try...

As long as its sealed your good. Does each outer leaf have the same mass?

Jason Morris, post: 461492, member: 51197 wrote: EVERYTHING goes thru the existing ceiling joists of that room. water pipes, wires, and a couple of HVAC lines feeding the dining room above.
however, we were very careful not to allow any framing or sheathing from the inner leaf to touch those joists.
The only thing that could feasibly be touching from one leaf to the other is insulation.

What type of insulation? Is it like barely touching or packed in? If its packed tightly it could count as a hard physical connection.

Rod specs 25% compression for the mineral wool fire safing that touches both the isolation wall and the existing ceiling.

Jason Morris, post: 461493, member: 51197 wrote: In the last pic (studio)You will see something at 125 and 250 registering. that is hand noise from me fumbling around taking the screenshot.
When im just holding it only 32 and 60 are registering at all.

So the ac is without a doubt contributing to the cause or is the entire cause. 60hz and 30hz, the octave below are where these machines run.

I tend to think its airborne noise bleeding right thru all the walls, and/or possibly some connected pipes shaking the existing structure.

It could be the unit itself shaking things, but since its on an earth dampened concrete pad, thats a good insulator. Does the house walls or foundation touch the ac pad? If not how close is it?

Gonna watch the vid asap.

From the pics your getting about 40db of isolation via all the walls which is a good amount at those frequencies.

Ran a test tone at 60hz in the studio, and got similar isolation level, then the problem would likely be a air borne. If you got more isolation with the test tone, that seems to say that some physical connection is bypassing the walls.

Im not a complete acoustical expert, so im trying to use what i know and suss things out.

This may be a case where some of the big dogs should be called. Im not sure if Andre Avare is still an active member here. Might be worth tagging him into the thread.

If you test the spl right outside the studio and inside, the difference should be what youd expect from the walls like that say 30db or so less inside the studio. If it isnt then that also seems to point to a flanking path shortimg out the walls.

Jason Morris Mon, 07/15/2019 - 12:25
kmetal, post: 461495, member: 37533 wrote: Does each outer leaf have the same mass?

Well, no. Three of the outer walls are 4" concrete. Everywhere else I beefed the sheathing up with 2 additional layers of 5/8" drywall.

kmetal, post: 461495, member: 37533 wrote: What type of insulation? Is it like barely touching or packed in?

Pinky fluffy insulation. its not packed in. I tried to compress no more than 20%

kmetal Mon, 07/15/2019 - 12:44
Jason Morris, post: 461496, member: 51197 wrote: Well, no. Three of the outer walls are 4" concrete. Everywhere else I beefed the sheathing up with 2 additional layers of 5/8" drywall.



Pinky fluffy insulation. its not packed in. I tried to compress no more than 20%


Ok cool so the wall mass is good, and sealed.

Im thinking there should be a 1" airspace between the studio wall/insulation, and the outer leaves. Are the concrete walls the only walls which are "connected" by the insulation.

I know limp mineral wool doesnt effectively transmit vibration, according to the book and rods drawings. I am not sure if the same holds true for pink fluffy.

When you added mass, were the stairwell, and the hall area leading to the garage hall (the right hand wall when walkimg toward garage hall) areas you added mass to? Are those the outer leaves of the studio wall?

Im thinking you may be correct about that green section of wall needing an outer leaf. Its a bit difficult to picture in my head. It seems to me that the garage hall is functioning as the outer leaf presently, and if so would need to be massed up if the wall section wasnt built.

The upside is that little garage hall is a perfect echo chamber as is! A Great companion to the nice tight drum sound in the booth. Drool. Id certainly run a couple mic and speaker cables out there.

Love, love, love, gretch kits. The most astounding snare i ever played was a gretch at a music shop. Im not a drummer, but ive had a couple beater kits over the years. The sound just lept off this snare, you barely had to touch it.

kmetal Mon, 07/15/2019 - 12:50
Since the AC is a nuisance anyway, it might be worth thinking about some double deflection neoprene pads for it to rest on, and some (flex) isolation connectors to break the coupling between the house an ac unit.

An ac company, or industrial supply co, might be able to help recconend some products. If i remember correctly mason industries website had tons of these types of things.

I wouldnt do anything until i was sure, but it might be worth considering.

Also, maybe there is a control on the ac unit that can make it run slower or quieter. Probably worth a call to the maker or installer.

Jason Morris Mon, 07/15/2019 - 13:03
The AC unit is pretty old. like 20 years old.
My cousin is an HVAC guy, so I can get a new unit for a pretty reasonable cost, but that is an expense that will have to wait. We are installing another AC unit along with a furnace up in the attic to cool the upstairs, as that old unit outside cant keep up. Its always like 10 degrees warmer on the upper level as it is on the main floor of the house.

The upside, is that I am planning to take a leg off the new AC/furnace system, coming down that hole I pointed out in the video and feeding that into the studio via another silencer.
Going to use a motorized damper to control it.
Hopefully THAT will go in next month. Maybe the following year I can think about replacing the ancient AC unit that is causing me so much trouble right now.

:/

Jason Morris Mon, 07/15/2019 - 13:09
kmetal, post: 461497, member: 37533 wrote: When you added mass, were the stairwell, and the hall area leading to the garage hall (the right hand wall when walkimg toward garage hall) areas you added mass to? Are those the outer leaves of the studio wall?

I beefed up the wall of the stairwell going from the basement up to the main floor.. That first one I pointed out between the mechanical room and my studio.
The door leading out to the garage.. that echo chamber area... nothing was beefed up there.

kmetal, post: 461497, member: 37533 wrote: Im thinking you may be correct about that green section of wall needing an outer leaf. Its a bit difficult to picture in my head. It seems to me that the garage hall is functioning as the outer leaf presently, and if so would need to be massed up if the wall section wasnt built.
Yeah. Nothing is beefed up in that area, so I think building another wall there is going to be the task for us this wed.

kmetal, post: 461497, member: 37533 wrote: The upside is that little garage hall is a perfect echo chamber as is!

yeah, it would be, except that it's isolated away from the drum room! The green wall seaparates that space from the studio.
Incidentally, that green wall is where my second set of silencers and the ventilation/hvac is going to come INTO the studio.

kmetal Mon, 07/15/2019 - 13:45
Does the wall in the stairwell have added mass floor to ceiling, or did it trace the steps? In the book it addresses maintaing isolation when a stairwell is involved.

Jason Morris, post: 461499, member: 51197 wrote: We are installing another AC unit along with a furnace up in the attic to cool the upstairs, as that old unit outside cant keep up. Its always like 10 degrees warmer on the upper level as it is on the main floor of the house.

The upside, is that I am planning to take a leg off the new AC/furnace system, coming down that hole I pointed out in the video and feeding that into the studio via another silencer.
Going to use a motorized damper to control it.

Id be very careful to make sure the new units are on isolation pads.

Id also make sure the unit has the capacity for the extra studio space, and the oversized ducting. In short id make sure the pro knows what you intend to do, and the specialized studio requirement details to keep it quiet.

Last thing you need is double the rumble.

Jason Morris, post: 461500, member: 51197 wrote: yeah, it would be, except that it's isolated away from the drum room! The green wall seaparates that space from the studio.
Incidentally, that green wall is where my second set of silencers and the ventilation/hvac is going to come INTO the studio.

The age old technique is to just have a speaker in the echo room, send the drums thru it, and record it with a mic. You can do this in realtime, or after the tracks are recorded.

If you're planning on a hole in that wall anyway, its probably worth a couple feet of cable. Redco makes xlr and 1/4" jack plates that fit in standard electrical boxes. Little bit of cable and a couple boxes would go a long way. You dont even need the boxes.

Jason Morris Mon, 07/15/2019 - 13:53
kmetal, post: 461501, member: 37533 wrote: Does the wall in the stairwell have added mass floor to ceiling, or did it trace the steps?

Floor to ceiling.

I grabbed 4 bags of mineral wool, and propped them in the corners of the room. Crazy how effective that stuff is.

I couldn't resist and threw some mics up to see how things were sounding with just a little bit of mineral wool on the walls and 4 unopened bags propped up in the corners.

[MEDIA=audio]https://recording.o…
Attached files DrumTest1.mp3 (2.4 MB) 

kmetal Wed, 03/21/2018 - 09:11
hey glad i can help. please excuse all the quotes, it helps me keep track.

Jason Morris, post: 456240, member: 51197 wrote: So, if I am understanding you I should fill those small 6"x3"x5" cavities just above the concrete wall with drywall.

yes.

Jason Morris, post: 456240, member: 51197 wrote: Also I should try to remove that insulation from the cavity above that.
I'm not sure how rough that will be. It's that blown in, glue-like stuff... Like "Great stuff" on crack... not the fluffy insulation.

what is behind that insulation? lol, if removing that insulation is as rough as it gets, you'll be the luckiest studio builder in history. if it comes down to it theres probably a 'best method' or trick, online. i hated wallpaper glue, and scotch tape resiudue, until i discovered murphys oil soap, and wd-40, melt that stuff away.

Jason Morris, post: 456240, member: 51197 wrote: Also, I AM using backer rod and Green-Glue acoustic sealant in the corners.

excellent! rods plans work, provided they're followed precisely. you can substitute the brand name 'acousitical sealant' for non-hardening silicone, or butyl caulking. save yourself some more money and buy it bulk, your gonna need alot of it. several cases gets expensive at $6 a tube.

Jason Morris, post: 456240, member: 51197 wrote: Regarding my ducts.. I'm not sure if re-routing is an option, because the way the room is built, there isn't really another place to route it in.
So I think my only option would be to not have any HVAC service to that room in the house. Personally, I don't much care, as the room doesn't get used a lot, but I feel that if I ever wanted to sell the place that could come back and bite me on an inspection and I'd potentially be required to put hvac back in the dining room.
I will think about it a bit though and see what the boss thinks of that idea.

tpypically residential hvac systems are overspec'd. theres a possiblity you could patch into some other ducting, perhaps in the attic, or thru the wall. Hvac is the area i know least about. in my experiences ducting either been there already, or we installed the ductless systems.

Jason Morris, post: 456240, member: 51197 wrote: I will try to get a new floor plan worked out in sketchup asap. I have an old sketch I did, but it included a "box" around a problematic water main that was exactly 2 feet into the middle of my drum room. I decided to break up the concrete and re-route that water main to the area that will be my "air lock" between the drum room and the control room.

where is the control room located? you are aware that air-locks diminish isolation a little right? just want to check.

Jason Morris, post: 456240, member: 51197 wrote: I was unaware that the fluffy insulation was better at absorbing bass. In fact, I thought it was the other way around? Ugh. Every time I think I have a handle on this stuff, I find out I read something wrong. :D
Is there a particular R-value you would recommend for between the joists? Should the whole cavity be filled?

im in over ten years, 6 studios, and taking graduate level physics online, and still scratching the surface of the acoustics world.

the R-value is whatever code calls for in those joists (which are 2x??). not sure how many layers of drywall your planning on, (with drums id be planning three), but you may have to use something sized down, if the drywall in the bays, and the ceiling design calls for it.

are you still planning an independently framed ceiling?

Jason Morris, post: 456242, member: 51197 wrote: At the time I did these, I was planning on an "inside-out" wall. After reading Rods book, I am wondering if I should should just build the walls an inch away from the existing concrete walls. I think it might be simpler and easier to seal up.

having only done it Rod's method, i can only attest that it works as prescribed. any time ive inserted my 'bright ideas' without verifying with an acoustician, it hasnt worked like i wanted. fortunately it only took a couple fails to learn. Rod generally describes the most efficient way to do everything. Its a great resource an had an immensely positive effect on my life and work.

i attached your sketch with some of my thoughts on it, some things are easier to express right on the pic.
I really want to make the space I have available as isolated as I possibly can, within the confines of what she will go for, or course! even if it costs a bit more $$ or takes me a bit more time.

i cannot stress how crucial this attitude is towards having it done right and within a reasonable budget. theres alot of planning involved, but willingness to take the time will pay dividends in the end. you never regret doing it right, and you'll only cry once at the bank. theres nothing worse than 'if i only had....' once the place is built and the budget is used.

have you taken some sound meter readings with and without you playing? do you have a working budget? what other rooms or gear are involved in the studio? do you have your electrical, lighting, and wiring planned? not trying to be overbearing, just trying to get a feel for the whole scope of the project, since its as strong as its weakest link. (enough cliches for ya? lol)

i always enjoy when people are willing to put in the effort and do these things right. there's too many hacks and myths out there.

cheers!!
Attached files

Jason Morris Tue, 07/16/2019 - 07:40
So, I have a boat load of mineral wool with specs as seen in the attached screenshot.
I am planning on doing corner traps in pretty much every corner I can.
I measured out for the soffit traps you mentioned, Kyle.. I'm just not sure I can bring myself to do that. They would hang out so far into the room as to make it unpleasant to be in there.
I think I'm going to have to go with either straddles or superchunks in each corner, including the wall to ceiling corners. I'm leaning towards superchunks. I know they are more costly than a straddle type corner trap, but I have a lot of the mineral wool already, and the stuff I am using is easily available to me, so I don't mind the expense.

So here is what I am wondering..

Considering my 8' ceilings (which are still considered 'too low' for good drum sounds) should I cover the entire ceiling with mineral wool? If so, should I then cover that with plastic sheeting to recover some of the mids and highs?
Floor is going to remain reflective of course.

I was considering doing a 'wiggly wall' as I have come to call it (sorta like in the picture attached.. that's not my photo but its a design I'm planning to copy). That wall would be my Helmholtz resonator.
The back and side walls I was planning to cover in mineral wool, and again cover THAT with plastic sheeting, cutting strips out so that it wouldn't act as a vapor barrier.

My concern is that as a drummer I don't want the room TOO dead. But I also wonder if "totally dead" is the best option for a room as small as mine.

would spending time creating REW files be worthwhile in a live room? or is that more useful for control rooms?

Does anyone have any thoughts?
Attached files

Jason Morris Wed, 03/21/2018 - 09:51
kmetal, post: 456256, member: 37533 wrote: what is behind that insulation? lol, if removing that insulation is as rough as it gets, you'll be the luckiest studio builder in history. if it comes down to it theres probably a 'best method' or trick, online. i hated wallpaper glue, and scotch tape resiudue, until i discovered murphys oil soap, and wd-40, melt that stuff away.

Behind that insulation is whatever sheathing is attached to the house, and then the brick veneer.
I haven't really tried to remove the insulation yet, and if that's what I have to do I will bite the bullet and figure out how to get it out of there.
However, I have been browsing around and I thought that I saw a post of Rod's where he talked about filling voids like that with closed-cell spray foam, which is what that is.
I realize there is no acoustic absorption benefit to doing so, but my understanding was that it would couple the drywall that I plan to install over those cavities to the sheathing on the other side of that cavity so they become "one leaf", thereby alleviating the "three-leaf" problem.
That was my thinking, but if you are pretty sure it's a better idea to scrape all that spray foam out of there and fill it with drywall, I'll get to scraping!

kmetal, post: 456256, member: 37533 wrote: several cases gets expensive at $6 a tube

$6? I'd love to pay 6 bucks! I've been paying 8 a tube for the Certainteed Green Glue from Menards.

kmetal, post: 456256, member: 37533 wrote: where is the control room located? you are aware that air-locks diminish isolation a little right? just want to check.

I was NOT aware that an airlock would diminish my isolation! Thank you! The "Control room" is really a pretty loose term for just a finished part of the basement that I have my gear set up in. The wifey was not keen on me ripping and rebuilding that whole area from scratch, as it was nicely finished, but she has become far more accepting of the ideas of adding drywall and acoustic treatment. I just had a door frame framed out last week so I can isolate that area a little more from the rest of the finished basement. It's not ideal, but it's what I have to work with. I attached some pics to give a better idea.

kmetal, post: 456256, member: 37533 wrote: are you still planning an independently framed ceiling?

Yep!

kmetal, post: 456256, member: 37533 wrote: have you taken some sound meter readings with and without you playing? do you have a working budget? what other rooms or gear are involved in the studio? do you have your electrical, lighting, and wiring planned? not trying to be overbearing, just trying to get a feel for the whole scope of the project, since its as strong as its weakest link. (enough cliches for ya? lol)

I have indeed taken some measurements.
My playing in the drum room is about 118DB when I am really whacking them.

Around the house, I got the following readings
Dining room (directly above the room I'm building the drum room in): 88 dB
Living Room: 72dB
My Sons room which is in the finished part of the basement: 86dB

The electrical panel is in a closet at the back of the room I am using for a control room. I haven't got the routes planned yet, but am planning on surface mounted boxes to cut down on the number of penetrations.
I have put some thought into running the other wiring. Planning on running PVC pipe from the control room to the live room. Not a straight run of it, but with a few bends, and maybe rubber couplers to help alleviate transmission noise thru the PVC.
Looking to cable for maybe 16 mics, 4 headphone returns, and a couple of ethernet cables, as I think if I build this right I should have terrible wi-fi coverage in this room.

And you are absolutely NOT being overbearing. I can't tell you how much I appreciate your input on this.


Regarding the comments on the picture.

I love the idea of using that hallway as a reverb chamber. Had not even considered that. Who doesn't love the "When the Levey Breaks" drum sound? Neat!

The other side of that wall is a closet, the stairway going upstairs (closet its beneath it). On the other side of the stairs is the furnace room, which is central to the basement. The other finished areas of the basement are around that. I'll try to draw things out more completely this week.

That area that I was planning on using as an Air Lock.. that could absolutely just be included as additional square footage in the drum room. However, that IS the area where I had to put that problematic water main/meter. If you dont think thats gonna be an issue, I will gladly extend the drum room into that space.

I have attached some more pics to give a better idea of what I am working with.

As a side note, the carpeting the the "control room" is going to be taken out.
Attached files

pcrecord Tue, 07/16/2019 - 07:53
Jason Morris, post: 461504, member: 51197 wrote: My concern is that as a drummer I don't want the room TOO dead. But I also wonder if "totally dead" is the best option for a room as small as mine.
I do have a too small drum room. It ended up near completly dead and I learned to work with it over the years.
I pretty good at faking it now with room simulators or plain reverbs.
I do have a hardware reverb for realtime mixing of my headphone mixes.
When ever I go play, I put on my headphones and get a feeling of a bigger room...
We'd all want the biggest room but get to work with what we have.
I'm sure you make yourself a good recipe that fits your needs ;)

kmetal Wed, 03/21/2018 - 11:35
Jason Morris, post: 456259, member: 51197 wrote: I realize there is no acoustic absorption benefit to doing so, but my understanding was that it would couple the drywall that I plan to install over those cavities to the sheathing on the other side of that cavity so they become "one leaf", thereby alleviating the "three-leaf" problem.
That was my thinking, but if you are pretty sure it's a better idea to scrape all that spray foam out of there and fill it with drywall, I'll get to scraping!

if you can somehow be absolutely sure that cavity is sealed, then add more blow foam and cut it flush with the studs, if you add drywall on top, itll be considered one leaf. it may require you to space the wall off the foundation an extra inch or so, which isnt the worst thing. its either that, or is gotta be taken out. if left as is, its a huge breach in the isolation. my prefernce is to remove it. it gives a chance to peek into the cavites for pipes, wires, and bodies, while keeping variables to a minimum.

Jason Morris, post: 456259, member: 51197 wrote: I have indeed taken some measurements.
My playing in the drum room is about 118DB when I am really whacking them.

Around the house, I got the following readings
Dining room (directly above the room I'm building the drum room in): 88 dB
Living Room: 72dB
My Sons room which is in the finished part of the basement: 86dB

great to have those readings!!!!

The electrical panel is in a closet at the back of the room I am using for a control room. I haven't got the routes planned yet, but am planning on surface mounted boxes to cut down on the number of penetrations.
I have put some thought into running the other wiring. Planning on running PVC pipe from the control room to the live room. Not a straight run of it, but with a few bends, and maybe rubber couplers to help alleviate transmission noise thru the PVC.
Looking to cable for maybe 16 mics, 4 headphone returns, and a couple of ethernet cables, as I think if I build this right I should have terrible wi-fi coverage in this room.

its good you've got a basic idea of the high and low voltage wiring, that can be used as a baseline for the plans, and evolve as needed. you may also want to plan on an hdmi or two, and some USB/data cables, for drives and peripherals. theres a good chance your gonna want a qwrty keyboard, and screen near the drums so you can operate the DAW from either room.

The advantage you have with the true Room-in-Room, is you can carry much more drywall, both on the existing structure, and the new one. you save money by not having to use clips, and channel based systems, or Green Glue, which are good products, but charge a premium for they're benefits. the more you can stick with standard the better, from cost, convenience, familiarity, and ease of use.

the place you have to commit to is how many layers between the joists. i'd aim no fewer than three, no more than five layers. 3 is probably the golden number, since you'll gain more performance from additional layers on the isolation walls/ceiling, than in between the existing joists. but if you got the moxy, by all means, as much as you and the bays can take is good, because its wont be easy to get to later.

while your doing the bays, is a good time to solidify the planning. having the plan complete before starting the new construction is essential. its impossible to plan for the unexpected things that are gonna crop up, so plan for everything you can.

your most likely gonna want your first layer of sheathing for the iso walls/ceiling to be OSB plywood. this offers structural integrity to the walls, lowers the resonant frequency, and is forgiveness for missing s stud thru 2 inches of drywall.

Jason Morris, post: 456259, member: 51197 wrote: I'll try to draw things out more completely this week.

cool. its hard to visualize things otherwise. a basic floor plan with, with poles, and other objects of interest noted, and some dimensions, and a basic gear list, would be great for keeping everyone on the same page.

Jason Morris, post: 456259, member: 51197 wrote: That area that I was planning on using as an Air Lock.. that could absolutely just be included as additional square footage in the drum room. However, that IS the area where I had to put that problematic water main/meter. If you dont think thats gonna be an issue, I will gladly extend the drum room into that space.

totally plan on using it for something!! a bass trap, storage, or just extra sqft, the more space you can have for the drums sound the better in this case. the first studio i built was for my uncles home studio, and i just boxed out the water main (which was in the control room) with a little access door on it to get to the shutoff. theres going to be good use for that area.

Jason Morris Wed, 03/21/2018 - 11:50
kmetal, post: 456260, member: 37533 wrote: if you can somehow be absolutely sure that cavity is sealed, then add more blow foam and cut it flush with the studs, if you add drywall on top, itll be considered one leaf. it may require you to space the wall off the foundation an extra inch or so, which isnt the worst thing.

That's pretty much what I was planning on doing. If I can't get a good seal between the drywall I install over those bays, and the foam, I will rip it out.
My buddy, who is helping me with this stuff, is a very talented carpenter. Between the two of us we will figure something out, or we will rip the foam out.

kmetal, post: 456260, member: 37533 wrote: theres a good chance your gonna want a qwrty keyboard, and screen near the drums so you can operate the DAW from either room.

I'm not sure if USB would be really useful over such lengths. I actually use my iPad for transport control of my daw when I record myself. I'm planning on connecting a wifi Access point inside the studio, connected to an ethernet cable going back to the main router.

kmetal, post: 456260, member: 37533 wrote: 3 is probably the golden number
Yep, 3 was what I was going to do

kmetal, post: 456260, member: 37533 wrote: your most likely gonna want your first layer of sheathing for the iso walls/ceiling to be OSB plywood. this offers structural integrity to the walls, lowers the resonant frequency, and is forgiveness for missing s stud thru 2 inches of drywall.

SO you think I should do a layer of 3/4" plywood, then two layers of 5/8 drywall?

kmetal, post: 456260, member: 37533 wrote: totally plan on using it for something!! a bass trap, storage, or just extra sqft, the more space you can have for the drums sound the better in this case. the first studio i built was for my uncles home studio, and i just boxed out the water main (which was in the control room) with a little access door on it to get to the shutoff. there's going to be good use for that area.

In my original 'vision' for that area as an "airlock" I was planning to treat the walls with mineral wool. maybe creating a dead space for vocals or a little amp room.
I would like to extend the drum room into that area, doing away with the air-lock idea altogether, but I am not sure how I could effectively build a wall around that water main without either making the water main and meter impossible to get to, or without hurting my isolation.
Do you have any ideas for how I would build a proper wall where that water main/meter is while still making the meter and shut off valve accessible?

kmetal Tue, 07/16/2019 - 17:15
Jason Morris, post: 461504, member: 51197 wrote: I think I'm going to have to go with either straddles or superchunks in each corner, including the wall to ceiling corners. I'm leaning towards superchunks. I know they are more costly than a straddle type corner trap, but I have a lot of the mineral wool already, and the stuff I am using is easily available to me, so I don't mind the expense.

Yeah those soffit traps eat space for breakfast. Glad you considered it tho.

The straddle traps are cheaper, but, the big consideration is they are more effective at absorbing bass. This is because standard fluffy insulation is better at bass absorption than rigid, due to a more optimal GFR. (Gas Flow Resistivity)

Did you order rigid or limp mineral wool batts?

Either way both trap styles are good and it wont make or break your build, especially since your adding so many. But if LF absorbsion is to be maxxed, straddeled is the way to go. Ive seen super chunk style where they cut fluffy batts into triangles and incorporated them in the bottom and top quarters of the trap, since bass builds up most in trihedral, 3 way corner junctions.

Jason Morris, post: 461504, member: 51197 wrote: Considering my 8' ceilings (which are still considered 'too low' for good drum sounds) should I cover the entire ceiling with mineral wool? If so, should I then cover that with plastic sheeting to recover some of the mids and highs?
Floor is going to remain reflective of course.
.

8' ceilings in a drum booth can sound good.

Id cover the area over the kit without question, and probably no plastic.

Id most likely cover the entire ceiling as well, probably no plastic.

It might make sense asthetically to leave the perimeter of the ceiling untreated or not, depending on how it meets up with your ceiling bass traps.

Off the top if my head, i tend to default to completely covered ceiling or 85% covered. No plastic (unless fiber dust concerns you. For me personally id cover in thin plastic for that reason. You can get like .3 mil (3 mil?) Plastic sheathing in a roll for cheap. Its in a big box like aluminum foil or wax paper. The effect of plastic is IMHO, much exaggerated as far as the real world. Cover your speaker in with some plastic wrap or a shopping bag, stand a few feet away and see how little it matters. Ive done this alot.

That said your cymbals probably dont need any HF reflections back into the mics.

Either way i think the difference is negligible. Even spaced slats dont liven things up as much as it looks like they would, ftom my experiences at least.



For ceiling id use 2" rigid with a 2" airspace. 4" rigid with a 2" airspace if youve got the headroom. Or use a 1" airspace. The 4" rigid gets you alot of absorbsion in the low mids. Your ceiling approaches becoming a huge bass trap with 4" and a 2" airspace. 6-8" rigid makes a true bass trap, but 4 with space is damn good considering its the entire ceiling.

That said, even 2" with no airspace will give you good broadband absorbersion. Low ceiling reflections generally arent useful. They are acceptable tho, just not directkt over the kit.

The cave's drum room has 10' ceilings and 3- 2'x4' panels (2" rigid) with i forget how much air space behind them, maybe 6".



Jason Morris, post: 461504, member: 51197 wrote: My concern is that as a drummer I don't want the room TOO dead. But I also wonder if "totally dead" is the best option for a room as small as mine.

You can add as you go. I like totally dead around the kit, then less as you move away from it.

Totally dead can be cool. But i was surprised at how decent the drums sounded in the cave booth, which was only like 8x10 and 8 ft tall. It had 2x4' panels along the walls and an almost bare ceiling. I tacked a couple small scrap foam peices to the ceiling, but it was mostly bare. Each wall and ceiling was splayed tho. We started tracking vocals and amps before i installed ceiling treatment, and it sounded good so i never finished it.
Perhaps i could have improved it more? Cant say, but the splayed ceiling is what i attribute to not 'needing' ceiling treatment.

Jason Morris, post: 461504, member: 51197 wrote: would spending time creating REW files be worthwhile in a live room? or is that more useful for control rooms?

It could be interesting. Id say its most useful if youve got some funny rings your trying to pinpoint. Other than that its more for general interest.

With tracking rooms you can move the mics and kit around to optimize the sound. And your shooting for flattering, not flat. This is why measurement is more 'mandatory' in control rooms, where listening position and speakers have less wiggle room.

I'll attach some screenshots from the triad site. I have much better photos in the chaos of my drives and cloud, but youll get the point.

Drums are in the main room, booths are the booths. The control room window gives perspective of the layout.
Attached files

JLDrumStudio Tue, 01/08/2019 - 21:59



Hi Jason, great information here. I’ve been reasearching for a few years and I have just started my studio build in our house that we moved into last year. I will be building an inside out ceiling and walls. I’m in a basement with three concrete walls. I’ve been beefing up the rim joist and won’t be long before I start adding two layers of drywall with green glue to the underside of the subfloor. I will be building a room inside a room. (Live drum room) 15’8 x 16’4. 7’7” to bottom of existing joist. Not a lot of ceiling room. The Joist are open web.
I have a couple of questions for you. Did you have a lot of nails sticking through your subfloor ? Did you cut them off if you did? As you can see in my pic. I only have 1 1/2 to get two sheets of 5/8 drywall because of my joist design. No room for 1/2” or 1” styrofoam to suck up the nails poking through like John Sayers site suggest.
I’m going to use 2x6 ceiling joist. Did you stick with 16” centers and make smaller modules to fit inside? How long were your modules? My span is a little more than yours but can’t sacrifice any headroom. I might have to sister the joist.

You have a lot of information I can use lol. I will be checking back often.
Oh yea, on my future ceiling modules I only have space for two 5/8 drywall. No room to add the plywood. Is that a problem?

kmetal Tue, 07/16/2019 - 17:18
Here's one of the tracks i recorded in the booth. 5 mics, and i think the door was shut, some of the songs we left it open partially and had a room mic. No samples, no mastering. I could probably do a better mix now but in 2012 thats how it came out that day. Yamaha kit.

[MEDIA=audio]https://recording.o…
Attached files Lefty_-_Where_I_GO(EP_version) Mp3.mp3 (4.8 MB) 

kmetal Wed, 03/21/2018 - 13:44
Jason Morris, post: 456261, member: 51197 wrote: My buddy, who is helping me with this stuff, is a very talented carpenter. Between the two of us we will figure something out

Those are the scariest words in home studio. in my mind theres nothing to figure out. a putty knife, chisel, and hammer, will have that out in ten minutes. i wouldnt give it a second thought, just keep it simple. dont mean to sound like an a$$. you can see two of my builds here http://triadrecording.com/ just so you have an idea of the type of projects ive done. im by no means a master, but ive got a good well rounded base, and learned from some really knowledgeable people. id just try and urge you to stick with the known, tried and true, whenever possible. its obviously your call, i have no attachment to the project.

Jason Morris, post: 456261, member: 51197 wrote: SO you think I should do a layer of 3/4" plywood, then two layers of 5/8 drywall?

yes. this is how Rod does most of his builds, and i believe added that detail to the 2nd ed of his book. i only have the first ed. what i wold also do upfront is consider the 'what if' three layers doesnt provide enough isolation. you have the option of more layers, or of using green glue upfront. if budget allowed, the green glue is a good bet, less dust, hauling, and hanging, but is a bit more expensive, than layers of drywall alone, and a toss up when it comes to installation. if its DIY then the GG becomes less of a price difference.

it dpends on alot of things, but i would look at it as three layers 'might' cover your needs, and it might realistically, but snare drums cut air, and peoples tolerence levels vary so, i would account for this in the provisional section of the budget.

Jason Morris, post: 456261, member: 51197 wrote: In my original 'vision' for that area as an "airlock" I was planning to treat the walls with mineral wool. maybe creating a dead space for vocals or a little amp room.
I would like to extend the drum room into that area, doing away with the air-lock idea altogether, but I am not sure how I could effectively build a wall around that water main without either making the water main and meter impossible to get to, or without hurting my isolation.
Do you have any ideas for how I would build a proper wall where that water main/meter is while still making the meter and shut off valve accessible?

those are good ideas and definate possibilities. if you build the wall around the pipe, you can put a door, or a small acessess panel there to get to the meter. as long as things are gasketed properly, and the door/panel is as massive as the wall (ie same # of layers of drywall) your all set.

kmetal Tue, 07/16/2019 - 17:37
Oh yeah, the wiggly wall. If you like the look then sure. I just worry about unpredictable angles in a small room. The wiggles arent going to greatly effect the efficiency of trap to any big degree. They could slightly improve or worsen the mids and highs.

Id opt either a convex shape like a barrel, or a slanted (splayed) wall. I like the splay because its got a predictable reflection pattern, and a continuously deepening bass absorption, from shallow side to deeper side.

Ill post screenshots from normandy. You see the slat wall on the side of the drums is splayed in two directions! We called it the williy wonka wall. Lol no right angles at Normandy. Quite the test of my carpentry skills and sanity. The mis-cut pile wasnt too big. Each board had a slightly longer lenght then its neighbor. ( i didn't frame the wall or sheetrock it, but refinished the interior treatment from bare wall)

The kit in the main room, which doesn't show up well in the pic, is in front of a convex wall.

The window wall of the booth is also splayed in 2 directions.

Again sorry for the lame screenshots. Traidrecording.com is the site.

Eventually i hope to post/publish the build diary of the two studios.

I think after seeing the finished product, id prefer visually if the slats were horizontally rather than up and down.
Attached files

Jason Morris Wed, 03/21/2018 - 14:31
kmetal, post: 456263, member: 37533 wrote: you have the option of more layers, or of using green glue upfront. if budget allowed, the green glue is a good bet, less dust, hauling, and hanging, but is a bit more expensive, than layers of drywall alone, and a toss up when it comes to installation. if its DIY then the GG becomes less of a price difference.

I'm already using Green Glue as I beef up the existing structure. I'm planning on Green Glue between each layer of drywall in my build.

kmetal, post: 456263, member: 37533 wrote: those are good ideas and definate possibilities. if you build the wall around the pipe, you can put a door, or a small acessess panel there to get to the meter. as long as things are gasketed properly, and the door/panel is as massive as the wall (ie same # of layers of drywall) your all set.

Ok. Maybe I'll give that some thought and see if I can come up with something. Thanks again!

Jason Morris Wed, 01/09/2019 - 08:31
Hi!

I am envious of your square footage, but I can't say I'd be eager to tackle that ceiling!
Do you know what the measurement is between your floor and the bottom of those ceiling supports?

JLDrumStudio, post: 460122, member: 51506 wrote: Did you have a lot of nails sticking through your subfloor ?

I did have nails poking thru, yeah.
I didn't clip off any of the nails though. I used the styrofoam trick for most of my bays. The first few, I bent the nails over and pounded them down flat. Wish I had not done that. It's not going to be fun if the wood floor above ever needs to come up. I know I read a comment by Rod on another forum where he strongly advised against cutting the nails, as it could lead to problems with your floor above.

JLDrumStudio, post: 460122, member: 51506 wrote: I’m going to use 2x6 ceiling joist. Did you stick with 16” centers and make smaller modules to fit inside?

I went with like 19.2" centers. I built the modules so that when they were completed I could easily fit a standard batt of mineral wool in the bay.
I sistered two 2x6 joists together as well. I probably didn't need to do that, but the cost for a few extra 2x6's seemed worth the extra structural strength, and I didn't really see a downside, so I did it.

My modules are about 4'8" long. Easily manageable with two people. Would be tough to install with just one person.

JLDrumStudio, post: 460122, member: 51506 wrote: Oh yea, on my future ceiling modules I only have space for two 5/8 drywall. No room to add the plywood. Is that a problem?

My buddy who has been helping me out with this is a great carpenter, and he asked me the same thing. "Hey do we need to use plywood on these modules? Maybe we can save you some money and just use 3 layers of drywall?"
My answer to him was "I Don't know. All I know is this is how I have seen it done by someone I consider an expert, so I would rather spend the extra money and do it that way than have to tear it all out and do it again if it doesn't work right."

So I guess thats is my answer to you, and I hope you don't view it as a cop out. What you are talking about doing makes perfect sense to me, but I'm not an expert, and the way you want to do it is a deviation from how I saw it done.
I wonder if the plywood helps keep the modules from twisting or flexing over the years?

Jason Morris Tue, 07/16/2019 - 17:49
kmetal, post: 461507, member: 37533 wrote: The straddle traps are cheaper, but, the big consideration is they are more effective at absorbing bass. This is because standard fluffy insulation is better at bass absorption than rigid, due to a more optimal GFR. (Gas Flow Resistivity)

Do you have any links to articles providing more detail about that? I'm not doubting you, but I have read conflicting comments about that and I am not sure what to believe.
I think I read where one of the guys from GIK acoustics said fluffy insulation was better at absorbing bass, but only when it was like 18" thick!
The specs for the Fire and sound batts, and what I saw regarding absorption coefficients on Bob Golds website seem to indicate that the mineral wool is better than the fluffy stuff for the depths I am willing to go. Im not wedded to the idea. I have plenty of fluffy insulation left over too. I just want to do what is going to work the best.

kmetal, post: 461507, member: 37533 wrote: Did you order rigid or limp mineral wool batts?

I guess it's technically rigid? I think its more medium density than high density though. the specs are posted above, but I dont know if they tell you what you are looking for?

kmetal, post: 461507, member: 37533 wrote: Or use a 1" airspace.

The stuff I have is 3", which I guess would leave like a 1/2" airspace if I went with the plan of placing the batts into the cavities of my inside out ceiling.

kmetal Wed, 03/21/2018 - 14:42
Jason Morris, post: 456264, member: 51197 wrote: I'm already using Green Glue as I beef up the existing structure

can you explain this a bit more? green glue is only effective in places they've tested and recommend it would be wasteful/inefficient otherwise..

Here's a quick illustration of what can be done around that pipe.
Attached files

Jason Morris Thu, 04/12/2018 - 10:22
So, I'm still delving down the HVAC rabbit hole. I think I have a little more understanding of certain things.. But to be honest there are so many variables floating around that I get a little lost in all of it.

The past day or so, I have been trying to figure out what I want to do about silencers.
As I think I mentioned, isolation is very important to me. I am shooting for 60db, and want to do whatever I can to hit that target.
I read on John Sayer's forum that in order to get really good isolation, Im better of putting a silencer on each leaf penetration.
But because of the lack of space in my drum room, I have very minimal area between my leafs for silencers.
So I am thinking about options.

One option is building a small silencer that can fit between the existing ceiling joists. That would put me at roughly 14" x 7 1/2" x 3' or so (i could go longer if I wanted)..
I could only feed that with a 4" duct (12.56 sq in.. I think) . The channels in the silencer would be 4x4 (16 sq in), and it would come out the vent at 4 x 8" (32 sq in).
I think that fits the requirements for doubling the cross section at the output of the silencer.

I guess my question is.. am I starting off with too small of a duct to begin with? I have seen other posts where people with similar spaces to mine had used 4" duct.. but that doesn't mean they did it correctly.

What do you think?

Jason Morris Tue, 07/16/2019 - 17:56
kmetal, post: 461509, member: 37533 wrote: Oh yeah, the wiggly wall. If you like the look then sure. I just worry about unpredictable angles in a small room.

I do like the look of it, and I was more interested in the varying depths of said wiggly wall than breaking up the reflections.
My wife likes the look of it as well, which is a plus. :D

BUT functionality would trump aesthetics.

I had initially planned on having wood slats on all of the walls. I think during my investigation I determined that might not be the best idea.
What are your thoughts? Use them? leave them out entirely? or just use a few, spaced far apart so as to be aesthetically pleasing but not have much affect on the acoustics?

kmetal Wed, 03/21/2018 - 14:45
as far as isolation goes, you should be Rock Ready! im glad your realistic from the get go about your requirements, that's usually the folly of most projects. glad to help, this stuff fascinates me. Cheers!

P.s In 'The Book' in the doors and windows, or hvac section, i believe, rod does as diagram of a little door for an iso wall where they use a Thru wall air conditioner, like what you put in a window. thew same concept can be applied to anything that needs temporary access.

kmetal Tue, 07/16/2019 - 18:49
Jason Morris, post: 461510, member: 51197 wrote: Do you have any links to articles providing more detail about that?

I should have may evidence if im going to make statements like that. A corner trap would fairly easily reach 18" depth from front face to corner. But i was talking from memory. I think studio tips had some info on it, and i am pretty sure GS had the thread i was thinking of. I think the thread were Eric Desart introduces the superchunk, there is test data. Originally on studiotips which is defunct i think, but still acessable. There's a gross amount on GFR, but there was one about the super chunk with fluffy.

The only firm reference i can surely think of is Rods bass designs in the book often use a rigid front with fluffy. If there was something better Rod would use that. His methods arent always cheapest, but i generally believe are most effective and cost effecient. It may have something to do with the fact that the fluffy is being ysed behind a rigif panel. Or it may just be that the rigid panel gives a clean fininsh look and is resistant to bumps and pokes.

I will look around to try and find that info, but i guess i would have call my statement conjecture until i provide proof. Although rods book is i guess some sort of proof. Normany employed rigid with fluffy behind it in the control room, and fluffy only in the booths. Again not trying to wiggle out of firm proof of my claim.

Jason Morris, post: 461510, member: 51197 wrote: I guess it's technically rigid? I think its more medium density than high density though. the specs are posted above, but I dont know if they tell you what you are looking for?

Its it the consistency of styrofoam roughly? If you hold it up flat does it maintain is form or flap around.

It would probably say "rigid mineral wool" on the package.

Jason Morris, post: 461511, member: 51197 wrote: I had initially planned on having wood slats on all of the walls. I think during my investigation I determined that might not be the best idea.
What are your thoughts? Use them? leave them out entirely? or just use a few, spaced far apart so as to be aesthetically pleasing but not have much affect on the acoustics?

Hey man if you like the wiggly go for it.

Id err dead around the kit. Then id probably add slats in sections. Maybe angle them away from the kit and or towards absorption areas. My biggest purpose for slats is for selectively absorbing bass frequencies. Like the 60 or 125hz boom in your room. They also look cool, but they are also very common. Ive been playing around with squiggly strips of plywood, as an idea for my next studio.

You could maybe add slats just to your bass traps in the corners. You could also do the wall you look at when playing the kit with slats, and a curtian for variable liveness but consistently tuned trapping. Id probably be looking at something that with a couple slat sections on each side. Something about slats on the wall/ceiling traps looks good in my minds eye. It might help add visual seperatation and highlight the cool angle of the super chunk.

I am alot less afraid of reflection than i used to be when i first got interested in acoustics. In regular rooms reflections are often nasty so it gives the impression that live is bad. Well designed rooms that are lively are a different animal.

Id honestly kill around the kit and do the ceiling and bass traps. Then id experiment with different amounts and locations of absorbsion. When it was good, id then do the slats, tuning them to the room mode. Then make sure the room still had the right level of life/death and cover it all up with fabric.

I was surprised to hear how much trial and error and listening (a novel concept) rod used in the powerstation. They just kept adding laquer coats till it sounded right. Ditto for normandy live room. The normandy control room was rebuilt 3 times from '78 to like '86 till it was amazing. Then i redid it in 2012 making some slight changes.

kmetal Tue, 07/16/2019 - 19:06
Im still trying to find the proof, but you can also do a super chunk style but with fluffy. Theres alot of comments that say less dense insulation is for bass traps, but like my comment, dont include a data sheet.

This is as close as ive gotten. Andre (Avare) doesn't supply a data sheet, but he id very very knowledgeable and well respected.

https://www.gearslutz.com/board/studio-building-acoustics/859555-insulation-superchunk-corner-traps.html

Ive only seen him incorrect once when rod presented a data sheet on the Noise Reduction of a wall with steel vs wood. Ive read hundreds or more of andres posts.

Im gonna keep diggin, but id feel personally comfy stopping right there and using fluffy to fill the cavity. Its my nuerosis that wants the data sheet.

Jason Morris Wed, 03/21/2018 - 15:05
kmetal, post: 456265, member: 37533 wrote: can you explain this a bit more? green glue is only effective in places they've tested and recommend it would be wasteful/inefficient otherwise..

I have been cutting 5/8 drywall into 14 1/2" strips to beef up the subfloor "leaf". So between my joists I have GreenGlue, drywall, GreenGlue, drywall, sealed with green glue sealant between each layer, then battened into place with 1x2. I thought that I got the idea from Rod's book, but I have read so many things on the internet, that maybe I'm conflating what I read in his book with something I read somewhere else.

At this point, the "beefing" is about 80% done, so if I did things wrong, hopefully, it is just wasn't cost effective. I'd rather lose the couple hundred bucks than all the time.

On another note, I decided to go down and see how easy it was to pull that insulation out.. Way easier than I thought. I will just go that route.

Thanks for the ideas about dealing with the pipe! I think I will do something like that too. :)

JLDrumStudio Wed, 01/09/2019 - 16:08

Thanks Jason for the quick response.
I’m 7 ft 7” right now to the bottom of my floor joist. I will have a ton of work up in my floor joist. I will just take it one step at a time. My next step is to beef up the subfloor. I’ve heard different things on the nails coming through the subfloor. Seems like they use to think it was ok to bend or cut but now they say the styrofoam is the salution. I understand that on a typical floor joist, that’s the best and easiest salution. Mine unfortunately is not typical I only have 1 -1/2 inch to beef up the subfloor. So, that’s a problem with the nails. I think I’m going to trim them leaving 1/8 sticking down. I will use some 1/4” polystyrene closed cell foam to cover the nails. Then two 5/8 drywall with green glue. That gives me 1-1/2 total so my cleats don’t have to be notched. I did look into the nail problem and it seems the hvac guys are running into the same problem when they put up thier heat transfer plates for floor heaters. They have just been cutting them by the hundreds. I dunno lol. Looks like I’m stuck cutting them.
Here is a scetch,by doing the inside out ceiling without the plywood I am 7 ft 1-1/2 to the bottom of my modules/ 2x6
I have plenty of time to think before I cross that bridge. Subfloor and existing hvac are making my head hurt. Oh what we go through for sound isolation.

Jason Morris Tue, 07/16/2019 - 19:18
kmetal, post: 461512, member: 37533 wrote: I should have may evidence if im going to make statements like that.

No worries man. I hope you know I wasn't trying to call you out. I'm just looking to find consensus among the various people I look to on the inter webs for. guidance. :)
Besides, it occurred to me I have both. I can just try them a. couple different ways and see how things go.

kmetal, post: 461512, member: 37533 wrote: The only firm reference i can surely think of is Rods bass designs in the book often use a rigid front with fluffy.

I need to crack it open again. I need to re-read his acoustics chapter.

kmetal, post: 461512, member: 37533 wrote: If you hold it up flat does it maintain is form or flap around.

It's floppy.

On a isolation related note...

I did as you suggested a few posts back and ran a sine (and saw) wave thru a speaker in my drum room and checked the levels 3 feet from the door with an SPL meter.

I tried to hit 100db in the drum room, and when I stepped back out side that room, with both doors closed I was getting readings at the noise floor level of the house, which, granted is not great. (about 54db)
UNTIL I hit that 30hz tone. Then I was hitting around 90db in the drum room and 72 right outside the door.

kmetal Wed, 01/09/2019 - 16:27
For the nails, i prefer banging them flat to the subfloor whenever applicable. Eaiser than cutting them, and doesnt mess with the fastening of the upper floor covering. Styrofoam is easier applied when you need to prevent tbe screws your using to fasten the drywall to tbe subfloor, from poking up thru the floor covering upstairs. It can work both ways, but it seems more difficult to install the stryofoam into a bunch of partially bent nails.

Id also verify with tbe Green Glue Company that its effective in your proposed application. I only recall seeimg test data for full sheets. Given the 1.5x price of gg relative to drywall id want to make sure it was working equally well, and as perscribed.

Inside out isnt my area of expertise, i know that in general isolation construction, plywood is integral being structural, allowing for a more rigid wall panel/partition (lowering resonant frequency of the assembly) and gives you something to screw subsequent layers of sheathing into.
x