Salem Oregon conference center studio

[Soundman2020]

Not sure what you are referring to as the "middle-leaf".

You are going to have a three-leaf ceiling: you have no choice. The outer-leaf is already up there: the roof deck. Then you will be building the middle-leaf: " fiberglass between the new joists ... then two layers of drywall,". Following that, you will build your inner-leaf: " When the inner ceiling is framed later, I will add Roxul then two layers of drywall.". That's three leaves. You need insulation between the outer leaf and middle leaf, and you also need insulation between the middle-leaf and the inner-leaf.

The unclear part is how to connect the Roxul under my smooth double layer of the outer-ceiling drywall.

Your outer-ceiling is already up there! It is visible in the photo: it is a plywood deck, on top of the trusses. To keep the insulation in place up there, do as I suggested: use strips of plastic stapled across the bottom of the trusses. That will keep it in place until such time as you are able to put the middle-leaf in place.

Then you will frame out the inner-leaf, and the same situation will repeat: use plastic stapled under the joists, to keep the insulation in place, until you are able to put up the drywall.

I just went to the FAQ at Roxul.com. Here's the answers to my fore-mentioned Roxul questions:

Excellent! The mystery is solved...

There is growing attention, interest and support from my peers to get this DONE

!!!

- Stuart -

[Guit-picker]

OK, I get what you mean about the "middle leaf". I wasn't counting the roof as a leaf. So it seems that you are talking about only two layers of insulation: Fiberglass between the ceiling joists (and above the middle leaf) and Roxul above my inner leaf. It's not the same scheme as my walls, but is it equivalent for sound isolation? I was thinking I needed another layer of Roxul just BELOW the middle leaf to make it like the walls (i.e. layers are: Roof plywood, air ventilation space, fiberglass, double drywall of middle leaf, Roxul (somehow), Air space, Roxul above double drywall on inner leaf). I'm guessing you are saying to skip the layer of Roxul just under the middle leaf and only put it just above the inner leaf. Correct? Sorry if I'm dense here!

To clarify, my walls will be (from outside to inside) siding, plywood, double drywall (against plywood as pictured), insulation, air, insulation, double drywall (8" between leaves, with 2nd set of framed walls, of course), just as Gervais describes.

You are a big help to me. Thanks for your patience!

[Soundman2020]

I was thinking I needed another layer of Roxul just BELOW the middle leaf

Maybe you missed it, but I think I already answered that question: "You need insulation between the outer leaf and middle leaf, and you also need insulation between the middle-leaf and the inner-leaf."

The air gaps between the leaves are the springs in the MSM systems. The insulation that fills those air gaps is the damping. Without that damping, you lose lots of isolation, so yes, you do need it, in both cavities: the one between the outer-leaf (roof deck) and middle leaf AND ALSO the one between the middle-leaf and inner-leaf.

I'm guessing you are saying to skip the layer of Roxul just under the middle leaf and only put it just above the inner leaf.

Nope! Not saying that at all. I'm saying that you DO need insulation in between the two leaves, and you need as much as possible. Filling the cavity only partially will not give you the full isolation. The cavity needs to be filled as much as you can afford to do, and hopefully 100% filled. In a typical situation, filling it just a bit will get you 5 dB or so of extra isolation, while filling it fully could get you as much as 16 dB of extra isolation.


- Stuart -

[Guit-picker]

Yes, please be patient with me, I don't think I'm coming across clearly with my question:

...and you also need insulation between the middle-leaf and the inner-leaf.

Yes, this has been understood all along and has been always the intention, but with the horizontal ceiling, I thought I needed to have insulation attached underneath the middle leaf to make it like the walls with an order like this, top to bottom:

roof plywood (outer leaf)
air gap (ventilation)
fiberglass insulation
double drywall attached to ceiling joists (middle leaf)
Roxul insulation (Attached to drywall somehow, which was the problem!)
Air gap
Roxul insulation in 2nd inner ceiling joists
double layer of drywall (inner-leaf).

So are you saying instead to have layers like this?:
roof plywood (outer leaf)
air gap (ventilation)
fiberglass insulation
double drywall attached to ceiling joists (middle leaf)
Air gap
Double layer of Roxul insulation in 2nd inner ceiling joists
double layer of drywall (inner-leaf).

The Insulated inner cavity between middle and inner drywall (air and insulation) is planned to be 8" in both the ceiling and walls.

Maybe putting ME in the layer would help..... I'M pretty dense!
Thanks for putting up with me!

[Guit-picker]

Well after delays, I’ve finally gotten most of the outer mass done. The two layers of ceiling drywall are up. Just about everything is sealed with OSI-SC175. I’ve got 46 bales of Roxul Save N Sound ready.

Ceiling_done_resized.jpg

I am honing in the inner wall layout. I hope it’s OK to continue this post at this stage on the “Studio Construction” page rather than starting a new one on the “Studio Design” page. Not sure what's the right thing to do. Here is what I’ve been working on for the last three years.

Floorplan_Forum_Submittal_A.jpg

The building is perfectly square to start with.
The ceiling is slanted on the North and South ends. The inner ceiling will be 6’ 9 3/16” on those edges.
The inner ceiling in the sound rooms will reach 9’ 3 ¼”
The inner ceiling in the control room is planned to be 8’.
I am considering using the space above the ctrl room for some of the fresh air venting. It looks like the best place to make room for it.
The rooms are symmetrical, but the ceilings are not.
The green areas are the start of the plan for acoustics – mostly bass traps, but probably some resonant panels on the sides of the control room? The green area in the front of the control room is bass traps situated above and below the windows.
The green around the monitors are planned to be soffits per the lengthy discussions on this forum.
The control room ratio is based on the L. W. Sepmeyer ratio in Gervais’ book. That’s where my greatest concern is at this time. Although I was aiming for a ratio of H/W/L = 8’/9.12’/11.2’, I realize that it is based on a rectangular room and mine isn’t. I tried to average out the width and in all of this I have some questions:

Am I on the right track with the cntrl room side wall angles?
When measuring for ratio, is it done from drywall to drywall or from finished surface (i.e. acoustic panels, bass traps, etc)?
Would I be smarter to raise the control room ceiling enough for a cloud? If so, how much additional room to allow for a cloud?

Another question that is nagging at me is the floors. I plan to have a separate floor for each of the four rooms. I am thinking of laying 2x4 flat on their sides and put sheeting on that. I would like to run channels under the floor for signal wiring between rooms (and insulation, of course). Is it better to place the walls directly on the concrete and build the floors in between the walls, or mount the walls on the edges of the floors?

Thanks for your inputs. The excitement is growing!
-Ron

[Soundman2020]

Am I on the right track with the cntrl room side wall angles?

The only way to tell for sure, is to do ray-tracing, to make sure the angles are large enough to create a true RFZ at the mix position. To me, it looks like your angles are too small.

Also, your mix position is way too far back in the room: bring it forwards, and adjust the speaker angles accordingly.

When measuring for ratio, is it done from drywall to drywall or from finished surface (i.e. acoustic panels, bass traps, etc)

Hard, solid room boundary, not considering any treatment inside the room. In other words, the actual surfaces of the room walls as you stand inside looking around right after you finish nailing up the last piece of drywall.

However, your room is not rectangular, so you cannot use the usual room mode calculators. Your room has seven sides (not six), and they are not mutually parallel. Room mode calculators are invalid for that.

Would I be smarter to raise the control room ceiling enough for a cloud? If so, how much additional room to allow for a cloud?

Yes. And "just enough". The cloud will sit over the area between the mix position and the speakers, so you know how big it will be. It also needs to be angled correctly to produce the RFZ in the vertical plane. so you know how far down it will come at the front. Use those two data points to figure out how much higher you'd need to make the ceiling.

Another question that is nagging at me is the floors. I plan to have a separate floor for each of the four rooms. I am thinking of laying 2x4 flat on their sides and put sheeting on that.

Bad idea. Here's why: http://www.johnlsayers.com/phpBB2/viewt ... f=2&t=8173 The same principles apply to you.

Is it better to place the walls directly on the concrete and build the floors in between the walls, or mount the walls on the edges of the floors?

See above thread: it is better to NOT build any additional floors. Just use the concrete as your floor. If you don't like how it looks, lay laminate flooring or ceramic flooring on the concrete. Any floor that has air cavities in it is a recipe for disaster (unless very carefully designed!!!)

- Stuart -

[Guit-picker]

Hey, Thanks Stuart! I'll go to work on it. Much appreciated!
-Ron

[Guit-picker]

I went to work on the Ctrl room layout and boned up on again on RFZ by reading Rod Gervais’ book, “Home Recording Studio …”, While playing around with the side wall angles, I had a tough time with the RFZ treatment area being exactly where the doors are. After making a radical bend in the side walls, I realized that the RFZ treatment (colored green) area now impacts the angled “rear/side” walls. Now my room ended up almost identical to Gervais’ example. I think I understand now why he did it that way.

I moved the mix position (red circle) forward 10 1/8” forward (38% of the room length from the front) and the focus point of the speakers (blue circle) is set behind that by 16”. This was the recommended method from the book. The purple circle was the former listening position AND speaker focus point.

The speakers were moved back 4” and out 3”. The original position of the left speaker is the white square (for illustration). The speakers and the focus point Form an equilateral triangle, although I wonder just how important that really is. I’ve seen references, I believe, and quotes of John that the angles can be up to 45 degrees. I’m a bit tempted to widen the space between the speakers and maintain the same focal point.

Layout_verG_RFZ_reduced.jpg

I’m going to work on re-drawing the new layout in 3-D for framing so we can get a Bill of Materials put together. I’ve got a framer partner who is ready and a group of restless people eager to see progress. We want to make use of this summer to move ahead.  If there are any drastic mistakes here, please let me know. Always thankful for your input.
-Ron

[Soundman2020]

After making a radical bend in the side walls, I realized that the RFZ treatment (colored green) area now impacts the angled “rear/side” walls. Now my room ended up almost identical to Gervais’ example. I think I understand now why he did it that way.

Yep! There's often really good reasons behind the things we do... and don't do!

I moved the mix position (red circle) forward 10 1/8” forward (38% of the room length from the front)

Excellent! That was an important change. In your case it doesn't really have to be 38%: that's only for rectangular rooms (and' its not even a rule anyway: just a rough guideline), but it was still necessary to bring the mix position forwards. I would probably bring it even further forward.

The speakers and the focus point Form an equilateral triangle, although I wonder just how important that really is.

It isn't. The side legs do have to be the same length, of course, but they don't have to be the same as the base (the distance between the speakers). That can change. which of course also implies a change in the speaker angles. The principle consequence is a change in shape of the sweet spot: making it more oval (either wider-than-long or longer-than wide), and a change in the sound-stage: spreading it more broadly,or narrowing it down. In both cases, that can be useful, as long as you don't over-do it.

I’ve seen references, I believe, and quotes of John that the angles can be up to 45 degrees.

Yup! Any angle between about 20° and 45° is possible. However, the more extreme you get, the further you are away from a "normal" control room, in terms of sound-stage spread, mostly. I try to stay within a range of about 25° to 35°, mostly.

I’m a bit tempted to widen the space between the speakers and maintain the same focal point.

Sure! Why not! It would give you more depth behind the speakers inside the soffit, which is always useful for framing and damping, and it would help your acoustics too.

I’m going to work on re-drawing the new layout in 3-D for framing so we can get a Bill of Materials put together. I’ve got a framer partner who is ready and a group of restless people eager to see progress.

A word to the wise: Do not rush! (OK, that's 3 words, not 1, so let me try again:) Patience! It would be a big mistake to start framing if your design is not fully complete, en every detail. I know you've been going at this for a long time already, and probably the pastor and the volunteers are getting a bit tired of not having a studio yet, but I'd really urge you to still take your time, and not rush things. There's a saying about the type of people who rush when angels don't...

For example, looking over your rough sketches so far, I don't see any provision for HVAC! That is critical. You still need to do all the calculations for that, to make sure you have your air flow rates and air flow velocities and air changes per hour and duct sizes and static pressure and latent heat loads and sensible heat loads and silencer box internal cross sectional ares and duct sizes and register sizes and open areas, and all the rest of it in order.... When I'm designing a complete studio, I often end up taking more time to design the HVAC system than I do to design all the rest of it together! It's a slow process...

I also don't see your framing plan for the soffits... that's also critical. You have to hold those speakers and the front baffles very rigidly, and have plenty of mass on there.... it's not evident on your sketches.

Your treatment plan is also on the lean side...

So please please please, slow down and don't do what the angels fear to do...

I’m going to work on re-drawing the new layout in 3-D

Yup!!!! When you have that done, feel free to post it here, so we can download it and rip it to shreds for you!


- Stuart -

[Guit-picker]

Thanks for your quick come back, Stuart! I moved the speakers out another 6.5”, still focused on the same point. Now they’re 33.3 degrees. The old placing is in white on the picture.

I’m sure liking the side walls better now that they’ve been flared outward. It gets the doors out of the way of the RFZ and allows more elbow room in the ctl room. The “vocal booths” on the left and right had a deep sharp corner that wouldn’t be very useful anyway.

I don't see any provision for HVAC! That is critical.

I am installing two ductless heat pumps units: One in the control room (South wall) and the other in the large sound room (West wall). That addresses the “H” and the “AC” part of HVAC. A separate ventilation system is going in above the control room and will house the silencers and feed out and back from the two rooms (separately, of course). The vocal booths will have to open the door when it gets stuffy - that’s decided. I have been talking to a good HVAC man who has done lots of work for our conference center and he is very intent on getting me a good ventilation system with silencers. He’s been on site twice to look over things and has my first framing diagram to start with. He is working out the first proposal for us now.

I don't see any provision for HVAC! That is critical….

I am installing two ductless heat pumps units: One in the control room (South wall) and the other in the large sound room (West wall). That addresses the “H” and the “AC” part of HVAC. A separate ventilation system is going in above the control room and will house the silencers and feed out and back from the two rooms (separately, of course). The vocal booths will have to open the door when it gets stuffy - that’s decided. I have been talking to a good HVAC man who has done lots of work for our conference center and he is very intent on getting me a good ventilation system with silencers. He’s been on site twice to look over things and has my first framing diagram to start with. He is working out the first proposal for us now.

I also don't see your framing plan for the soffits...

I have searched through some of the posts of the forum and have seen a lot of good stuff to start with there. I will draw up a first draft very soon. I admittedly just drew out a section (teal blue color) that I expect to build the frame for the soffets on what I learn from the forum. From what I’ve seen so far, I believe I’ve left enough room for that.

I need a lot more understanding about bass traps and RFZ treatments and need to bone up on that. I have seen numerous diagrams on building bass traps, especially John’s design and variations, but most of what I’ve found are in 2D and I’m having some trouble getting the whole picture. I plan to make some drawings of what I THINK should be correct based on what I’ve seen and go from there. Have to get to that soon too.

The room treatments are, admittedly, pretty much arbitrary. The Bass traps are lime green and RFZ (which I believe cover higher frequencies) are olive drab. I just ignorantly picked 6” for depth and added 18” either side of the RFZ point. I figured I would learn the details a bit later (I know what you’re going to say about that!).

Layout_verG2_RFZ_reduced.jpg

In the end, the tuning of the room is the most frightening thing to me but I’m eager to learn. When I considered getting into electronics in 1978, it sounded frightening then too….. but I learned…. And it isn’t bad at all!!!

There's a saying about the type of people who rush when angels don't...

Good point. I’m being as careful about stupidity as I can. They DO have a rudimentary place to do recording in the meantime. There’s another saying, though, that I’ve saw in an electronic engineering magazine and at work: “There comes a time in every project when you have to shoot the engineer and ship it”. Good point. I’m being as careful about stupidity as I can. They DO have a rudimentary place to do recording in the meantime. There’s another saying, though, that I’ve saw in an electronic engineering magazine and at work: “There comes a time in every project when you have to shoot the engineer and ship it”. As you very-much know, I’m up against that!

I “bravely” tried enclosing the latest sketchup file but it is too big and I get an error.

I spent the entire 3-day holiday weekend on this computer! It’s independence day, it’s 10:00pm and it sounds like a war zone out there!

-Ron

[Guit-picker]

Here is a birseye view of the floor plan "painted" on the floor and the framing, so far, of the control room. (Couldn't get the sketchup file to load. Got an error message.)

Never mind the console surface. I'm just playin' around with the shape!

Corner_CntrlRm_floorplan_G2_birdseye_reduced.jpg

-Ron

[Soundman2020]

I moved the speakers out another 6.5”, still focused on the same point. Now they’re 33.3 degrees.

Looks fine to me, except that the axes of the speakers do not seem to be perpendicular to the front faces? Probably your axis lines are attached to each other at the old intersection point, so when you move the speakers, the point didn't move: it stayed where it was, and the lines just angled a bit more, away from 90°. That's one of the quirks of SketchUp... You need to make the axis lines into "components" so that doesn't happen.

I’m sure liking the side walls better now that they’ve been flared outward. It gets the doors out of the way of the RFZ and allows more elbow room in the ctl room.

I am installing two ductless heat pumps units: One in the control room (South wall) and the other in the large sound room (West wall). That addresses the “H” and the “AC” part of HVAC. A separate ventilation system is going in above the control room and will house the silencers and feed out and back from the two rooms (separately, of course).

The vocal booths will have to open the door when it gets stuffy -

Why would air move in or out when you open the door? That's like saying "The jam will rise out of the jar when I take the lid off". No it wont. Not unless you tilt the jar to give it a reason to move. Ditto with your booth: the air won't come out unless you give it a reason to come out: There has to be a second path that air can follow as well as a pressure differential between the two paths, in order for that to happen. In a typical house, that isn't an issue at all, since there are multiple tiny "leaks" into and out of all rooms. But in a studio, all rooms are sealed absolutely air-tight: they are hermetic, twice over. No reason at all for air to move if the only path is an open door.

You seriously need to re-think your ventilation plan here!

admittedly just drew out a section (teal blue color) that I expect to build the frame for the soffets on what I learn from the forum.

Soffit framing is rather complicated: multiple strange angles, and serious bracing, plus shelves, support points, ventilation paths, ....

The room treatments are, admittedly, pretty much arbitrary. The Bass traps are lime green

The entire bottom section of each soffit, below the speaker shelf, is bass trapping. And I often leave an open section above the top of the soffit, where I add even more bass trapping. To me, it looks like you don't have enough bass trapping in that room.

I just ignorantly picked 6” for depth and added 18” either side of the RFZ point. I figured I would learn the details a bit later (I know what you’re going to say about that!).

“There comes a time in every project when you have to shoot the engineer and ship it”. Good point.

Possibly, ... but only if there's enough engineering in place already that the product will actually power up, and do what it is supposed to do! Or at least make a vague attempt to pretend that it works...

I “bravely” tried enclosing the latest sketchup file but it is too big and I get an error.

It's probably too big to upload: there's a limit on file size. Try purging the file (SketchUP allows a lot of unused geometry to accumulate in the file: you need to purge that manually, every now and then). OR upload the file to a file-sharing service, and post the link here.

- Stuart -

[Guit-picker]

Thanks Stuart, as always, for all your comments. I've been away a bit and just noticed your reply.

Looks fine to me, except that the axes of the speakers do not seem to be perpendicular to the front faces?

That's because I took off the axes lines. Those lines show the RFZ reflections on the walls, not the axes of the speaker. I took that off because it was making the drawing so busy. Sorry for the confusion. The blue dot is the spot that marks the apex.

Cheers,
Ron

[Guit-picker]

You seriously need to re-think your ventilation plan here!

OK, you convinced me. We added another branch to the ventilation to the Vocal1 booth plan (the one to the left of the control room). The one to the right is actually an entryway but CAN be used as a vocal booth in a pinch. Since it will not likely be used much at all, and the fact that it opens to the outside as well as the control room, we are not adding more ventilation to that room.

Thanks for looking out for me!
-Ron

[Guit-picker]

I finally was able to make the time to give an update on the studio progress. Sorry that I disappeared for about 22 months, but you wouldn’t believe the schedule I’ve had to keep in order to keep the studio work going as well as the rest of life. The help I’ve received on this forum has been instrumental and several times I was guided away from certain disaster in the design. Thank you so much for that! …. especially to Soundman2020

Here is a summary of the last two years (pictures and more details follow):
When I last posted, the outer walls were nearly complete with two sealed layers of drywall mounted to the inner side of the plywood exterior sheeting between the studs. Since then we’ve pulled in bigger power to handle the power budget for HVAC, lighting, and electronics and moved the breaker panel. We insulated the outer walls with Rockwool and framed the inner walls for four separate independent rooms.

We installed two ductless heat pumps and a fresh air system with baffled vents. We finished the AC wiring and put in signal conduits, then insulated the inner walls. Next came interior drywall – (ceiling, walls, acoustic seal, ceiling, walls , acoustic seal again). Texturing and painting came next. Next came the installation of four sets of opposing solid core doors and two windows. We are currently finishing up with rubber door seals & adjustments and have begun installing flooring. Flooring has to wait in the control room until the front soffit area and back bass traps are built (I will be having some detail questions on that soon - sometime after this update and after I search the forum first!).

Photo 1: Insulating outer wall in progress:

1A_20160731_220656.jpg

Photo 2: Framing drawing of the four inner rooms. The control room ceiling is limited to 8’ to allow fresh air system to be installed overhead:

2A_20160719_061928.jpg

Photo 3: Moving the breaker panel to inner wall. We put up a patch of two layers of drywall (offset) so we could seal around the in/out conduits – both on the inner side and outer side:

3A_20161227_212640.jpg

Photo 4: Part of the fresh air system with interior baffles (hard to photograph):

4A_20170113_164604.jpg

Photo 5: Recent photo of exterior heat pumps and new paint:

5A_20180513_180350.jpg

Photo 6: Fresh air input and outgoing fan. (Door and trim awaiting paint):

6A_20180513_181050.jpg

Photo 7: Interior units are also mounted on 2-layer offset drywall to allow to seal seal on both sides of drywall with OSI SC175 acoustic seal:

7A_20170222_105306.jpg

Photo 8: Showing detail of inner power wiring method and signal conduit on a back wall. We came up with this method for the AC wiring using Romex and a short piece of conduit to extend through the two layers of drywall. Each layer gets sealed as well as the inside of the conduit. I haven’t seen this anywhere else. I show more detail below:

8A_20170401_213511.jpg

Photo 9: Second layer of drywall nearly done. Each layer is sealed with acoustic seal in corners and anywhere a common joint is on both layers:

9A_20170803_182051.jpg

(continued to next post)