John Sayers' Recording Studio Design Forum Archive

Hey everyone,

I came across this board a couple weeks ago as I was starting more intensive research on putting together vocal booth. Such a great resource! I have been searching through the old topics to glean what I could from them and start putting my ideas down. I've reached the point where I'm hoping I can finalize a plan and start building in the next couple weeks, but I figured it would be wise to ask you all (as you know way more than I do!) to make sure I haven't missed anything before I get too far into it.

First, a little background. I'm a professional opera singer and voice actor by trade. As a result, I make a lot of noise at times (full volume practicing can reach 100db, though obviously not all the time, haha!). 2 years ago, we welcomed our first kiddo into the world, which is amazing. It has, however, meant that I can't really practice after he goes to bed, eliminating a lot of time I used to use to prep for concerts and shows. As a result, I am looking to create a small vocal booth in my basement that will work to dampen my practicing to a volume that won't really be heard from his room (which is right above my studio) and to also be able to record VO works and audiobooks during the day when there are people upstairs). I was originally looking into things like the Whisperroom, which would likely be just enough isolation, but realized I could likely do better for less money. Hoping for around 50db in reduction. Thankfully I don't really have any major bass-y sounds coming into the house.

The plan is for the booth to be semi-permanent (ie. I don't plan on moving it unless we move out of our current home, which could happen in a few years), so I was thinking that basing it off of John's vocal booth design on this site might be a good starting point (thanks for that John!). The size is about what I have available. I have roughly 5.5x7.5ft to work with and 7ft in height, with some ability to widen or narrow in places to accommodate non-parallel walls. I was thinking of doing a drywall GG sandwich for the outside walls, insulation in the frame, and cloth on the inside. I would then use acoustic sealant to deal with the corners/joins inside or outside. Then I would do corner traps, similar to John's booth design (a triangle frame from floor to ceiling with insulation in it and space behind), though I could potentially fill in behind them as well if that was a better idea.

As I will only be using this for myself, I don't need a window, though I may install one at a later date if it made sense. Also, any VO work I do will have all my recording gear in the booth (fanless laptop and audio interface, so it makes no noise). I will likely just need to bring in a power bar through the wall, and won't be doing ventilation at this point either.

So, to recap:

Single leaf vocal booth, semi permanent.
- Dimensions: approx 5.5x7.5x7 (length and width slightly movable), non-parellel walls
- No ventilation or window needed
- 50db in noise reduction
- Installation in basment on concrete floor
- Budget: $1000CAD

Plan
- Double drywall GG sandwich for outside walls
- 2x4 frame with insulation (I got a bunch of free Roxul R14 from a construction job which will be good for most of it)
- Cloth cover over frame
- Corner ceiling to floor bass traps (triagle shaped with insulation and air behind)
- Use acoustic sealant on any seams where necessary
- Put 1-2 extension cords in through wall for power and lighting

I'm sure I'm missing something, but hopefully this is a good place to start. I have starting trying to toy with Sketchup, and as I figure it out more and start laying out the plans, I will try to put up a picture/sketchup file as well.

The one thing I couldn't figure out was for the booth floor on the concrete floor. It looks like building a floating floor for this kind of setup is unwise, but I haven't been able to find an explanation on how to build and seal one from sound otherwise (sorry if I missed the topic in the boards!) Should I simply lay a piece of plywood down and call it a day? Or put the acoustic sealant +/- backer where the floor meets the frame?

Thanks so much in advance for the help! looking forward to getting started on this in the coming weeks. I will post pictures once it is underway!

Matt

Welcome Matt!

hoping I can finalize a plan and start building in the next couple weeks

Doable but remember, draw the entire thing with SketchUp Make so that you work out every issue before you build it!

non-parellel walls

You don't need this. Build it rectangular. Use the corners for bass trapping. Visually in the end it will look like there are non-parallel walls, but in reality, the structure itself will be perfectly rectangular.

- No ventilation or window needed

This should read no ventilation wanted because realistically, it is needed. If I were you, I would draw up a ventilation plan in your SketchUp model so that you can add it later.

- 50db in noise reduction

That's a pretty steep number so you're going to have to design it well with isolation in mind.

- Double drywall GG sandwich for outside walls

What about your inside walls?

- Put 1-2 extension cords in through wall for power and lighting

I would run a few ethernet lines and balanced cabling through in case you want to record someone else there in the future or maybe have someone else engineer while you perform. The ethernet can work for video or audio monitoring.

I'm sure I'm missing something

Due to the size of your room, you MIGHT need to use one crazy super door instead of two. You haven't mentioned doors yet.

I have starting trying to toy with Sketchup

Just stay away from SketchUp Free. It's brutal.

The one thing I couldn't figure out was for the booth floor on the concrete floor. It looks like building a floating floor for this kind of setup is unwise, but I haven't been able to find an explanation on how to build and seal one from sound otherwise (sorry if I missed the topic in the boards!) Should I simply lay a piece of plywood down and call it a day? Or put the acoustic sealant +/- backer where the floor meets the frame?

If you want to float the booth, do it like this:

http://www.johnlsayers.com/phpBB2/viewt ... it#p150345

Personally since it's just voice, I wouldn't bother.

Greg

Hi Greg,

Thanks so much for answering my questions. Much appreciated! A couple follow up questions for your answers (and answers to some of the questions!).

Doable but remember, draw the entire thing with SketchUp Make so that you work out every issue before you build it!

Definitely planning on it.Gonna be sitting down to do some learning of it in the next couple days.

You don't need this. Build it rectangular. Use the corners for bass trapping. Visually in the end it will look like there are non-parallel walls, but in reality, the structure itself will be perfectly rectangular.

Oh yeah? I was under the impression that the parallel walls, especially in smaller booths, can lead to mode problems. If I'm understanding you correctly, you're saying that adequate bass trapping will prevent those issues?

This should read no ventilation wanted because realistically, it is needed. If I were you, I would draw up a ventilation plan in your SketchUp model so that you can add it later.

Fair enough. I think the big thing for me here is to get it up and running as quickly and affordably as possible since I am heavily limited in recording and practicing time right now without it. I feel like the extra time needed to add these, especially ventilation, would be significant. Or am I wrong?

That's a pretty steep number so you're going to have to design it well with isolation in mind.

Yeah, true enough. I could probably get away with less quite honestly. Maybe in the 40-45db range. But figured I'd aim high first, as the 50db would make it possible to do all my work and any hour without issue, whereas lower might mean I still need to keep to more reasonable hours.

What about your inside walls?

I was thinking of just putting up cloth over the insulation itself (as per John's vocal booth design). From a sound isolation perspective, though, it may not be enough with just the outside walls and insulation, eh? The other idea I was considering was doing a single drywall mounted on resilient channels inside.

I would run a few ethernet lines and balanced cabling through in case you want to record someone else there in the future or maybe have someone else engineer while you perform. The ethernet can work for video or audio monitoring.

I hadn't thought of ethernet. That's a great idea. Might be worth considering it, even if I'm not planning on doing it now.

Due to the size of your room, you MIGHT need to use one crazy super door instead of two. You haven't mentioned doors yet.

Yeah, the plan is to go with one door if I can. I was thinking of getting the thickest solid core door I could find, treating for an airtight seal, and then adding treatment to the inside of it. I just found your post on "super doors" in another thread. Need to take a longer look at it. At first glance though, they look awesome, but I'm worried that the door alone will blow the budget. Would it make sense, say, to put GG on the outside of a solid core door and then plywood or some such?

Just stay away from SketchUp Free. It's brutal.

Will do!

If you want to float the booth, do it like this:

http://www.johnlsayers.com/phpBB2/viewt ... it#p150345

Personally since it's just voice, I wouldn't bother.

Yeah, I was thinking it wouldn't be necessary to float the floor given that it is voice and already on concrete. Is there a thread or place I missed on how to put a non-floating floor down? Do you just lay subfloor ply, cover it with flooring and trim, and call it a day? I feel like there should be caulking or some such?

Thanks so much for all the help. I'll be sure to post questions and progress as I make it!

Matt

Oh yeah? I was under the impression that the parallel walls, especially in smaller booths, can lead to mode problems. If I'm understanding you correctly, you're saying that adequate bass trapping will prevent those issues?

It will help. Angling your walls won't help either though. Bass trapping is your best bet.

I feel like the extra time needed to add these, especially ventilation, would be significant. Or am I wrong?

You're right. Ventilation is a major job in both design and build.

I was thinking of just putting up cloth over the insulation itself (as per John's vocal booth design). From a sound isolation perspective, though, it may not be enough with just the outside walls and insulation, eh? The other idea I was considering was doing a single drywall mounted on resilient channels inside.

With just cloth, then you're relying entirely on mass law which won't get you much isolation. Clips and hat will help a lot. I wouldn't do just resilient channel.

Yeah, the plan is to go with one door if I can. I was thinking of getting the thickest solid core door I could find, treating for an airtight seal, and then adding treatment to the inside of it. I just found your post on "super doors" in another thread. Need to take a longer look at it. At first glance though, they look awesome, but I'm worried that the door alone will blow the budget. Would it make sense, say, to put GG on the outside of a solid core door and then plywood or some such?

For a door, I wouldn't bother with GG. I would just add at least one layer of thick MDF to it to make it have a bank vault style sealing system. Use an automatic door closer to hold the door tight against the seals and avoid the use of a door knob that puts a hole through the door as it will trash your isolation.

Yeah, I was thinking it wouldn't be necessary to float the floor given that it is voice and already on concrete. Is there a thread or place I missed on how to put a non-floating floor down? Do you just lay subfloor ply, cover it with flooring and trim, and call it a day? I feel like there should be caulking or some such?

You can either just leave the concrete or paint it. If you want flooring on it, just treat it like a normal floor with underlay and the flooring (like laminate or whatever). I've seen people use that rubber puzzle piece play mat type stuff as flooring as it keeps your feet warm and it's cozy to stand on. I can't speak of it's effects acoustically though. I doubt it's very harmful and it's super cheap so it might be worth looking into. Just know that it doesn't like sharp stool legs stabbing into it!

Greg

Thanks Greg! I answered the questions and asked a couple more below.

It will help. Angling your walls won't help either though. Bass trapping is your best bet.

Great. Not having to angle the walls saves a ton of cutting time. Mind me asking how come so many here talk about the importance of non-parallel walls in small booths then? I was always under the impression in was nearly imperative to avoid the boxy/boomy sound (along with bass trapping, of course).

You're right. Ventilation is a major job in both design and build.

I may have to avoid it for now and plan the possibility of an upgrade later, given the time frame and costs associated.

With just cloth, then you're relying entirely on mass law which won't get you much isolation. Clips and hat will help a lot. I wouldn't do just resilient channel.

Makes sense re: mass law. For the RC, you don't think it would be enough on its own? John's studio manual has a single drywall on both sides with one side having flexible channel pegged at 47db isolation (with insulation). I figured that having the other side with a GG sandwich would easily bump that over 50. Or am I missing something? Is that flexible channel not the same?

For a door, I wouldn't bother with GG. I would just add at least one layer of thick MDF to it to make it have a bank vault style sealing system. Use an automatic door closer to hold the door tight against the seals and avoid the use of a door knob that puts a hole through the door as it will trash your isolation.

Smart! I saw one person use something like that in my research. Looks like it could be a good option. Any suggestions on where to source an affordable commercial grade door closer in Canada?

You can either just leave the concrete or paint it. If you want flooring on it, just treat it like a normal floor with underlay and the flooring (like laminate or whatever). I've seen people use that rubber puzzle piece play mat type stuff as flooring as it keeps your feet warm and it's cozy to stand on. I can't speak of it's effects acoustically though. I doubt it's very harmful and it's super cheap so it might be worth looking into. Just know that it doesn't like sharp stool legs stabbing into it!

The concrete floor has old school 80s tiles on it already (no underlayment or anything). I was thinking of grabbing a floor underlayment (neoprene or something) and a box or two of cheap vinyl flooring from my local ReStore (they frequently have 40-50sq ft leftover for like $30). I assume that would work?

I started working with Sketchup in the past two days. Watched some of the suggested tutorials on components, inferencing, etc... It's definitely a learning curve for someone who has never used that kind of software before!

Thanks again! I really appreciate the help.

Matt

Great. Not having to angle the walls saves a ton of cutting time. Mind me asking how come so many here talk about the importance of non-parallel walls in small booths then? I was always under the impression in was nearly imperative to avoid the boxy/boomy sound (along with bass trapping, of course).

Can you link me to some threads/posts talking about the importance of non-parallel walls?

Check out Abbey Road's live room. Notice how it's rectangular with parallel walls? This is believed to be one of the best sounding rooms in the world.

Makes sense re: mass law. For the RC, you don't think it would be enough on its own? John's studio manual has a single drywall on both sides with one side having flexible channel pegged at 47db isolation (with insulation). I figured that having the other side with a GG sandwich would easily bump that over 50. Or am I missing something? Is that flexible channel not the same?

Two layers of 5/8" drywall will give you 32.93dB of isolation in a perfect construction -- no doors or windows to potentially screw up your isolation!
RC has a direct connection through metal to the studs. Clips and hat will have more isolation through rubber.

Any suggestions on where to source an affordable commercial grade door closer in Canada?

Here is the one I would buy if I were you:

https://www.amresupply.com/part/13-1900 ... UXE-CLOSER

The concrete floor has old school 80s tiles on it already (no underlayment or anything). I was thinking of grabbing a floor underlayment (neoprene or something) and a box or two of cheap vinyl flooring from my local ReStore (they frequently have 40-50sq ft leftover for like $30). I assume that would work?

I started working with Sketchup in the past two days. Watched some of the suggested tutorials on components, inferencing, etc... It's definitely a learning curve for someone who has never used that kind of software before!

Put everything in layers. Make each item (such as a 2x4) a component by selecting it and hitting "g" on your keyboard. Inference is so critical. Moving items using your arrow keys to lock it to an axis is so helpful.

Greg

Can you link me to some threads/posts talking about the importance of non-parallel walls?

John's vocal booth design here http://www.johnlsayers.com/phpBB2/viewt ... =1&t=14147 has the walls out of parallel. Similarly, Rod Gervais in his Build it like the pros book talks about how building out of parallel helps "stop issues with flutter echo and comb filtering." He says "if you're building from scratch, facing walls cane be made out of parallel by at least 1 in 10 (6%)" though he does say if it isn't possible, you can use absorbers. That's most of where I was getting my info from. Though on here is seems like some (such as Waka) suggest not doing that, especially for control rooms.

Two layers of 5/8" drywall will give you 32.93dB of isolation in a perfect construction -- no doors or windows to potentially screw up your isolation!
RC has a direct connection through metal to the studs. Clips and hat will have more isolation through rubber.

I didn't realize that RC still transferred a fair amount if installed properly. Again, most of the info was from Rod Gervais regarding his writing that RC1 and RC2 both would work well for decoupoing walls and ceilings.

As for the drywall, is that the same with 2 layers in a GG sandwich? I was getting most of my info from http://johnlsayers.com/Recmanual/Pages/STC%20Chart.htm which had the flexible channel info.

Here is the one I would buy if I were you:

https://www.amresupply.com/part/13-1900 ... UXE-CLOSER

Awesome. Thanks so much!

Put everything in layers. Make each item (such as a 2x4) a component by selecting it and hitting "g" on your keyboard. Inference is so critical. Moving items using your arrow keys to lock it to an axis is so helpful.

Much appreciated! Gonna work on it some more tonight.

Thanks!

Matt

John's vocal booth design here viewtopic.php?f=1&t=14147 has the walls out of parallel.

Maybe John can chime on this if he sees it but personally, if I had the space to angle my walls, I would prefer to use all available space and make the booth as big as possible. I'd then utilize the space to bass trap as much as possible.

I didn't realize that RC still transferred a fair amount if installed properly. Again, most of the info was from Rod Gervais regarding his writing that RC1 and RC2 both would work well for decoupoing walls and ceilings.

It does help, for sure. But isolation clips are going to work better.

As for the drywall, is that the same with 2 layers in a GG sandwich?

The GG will help some. Mostly at the coincidence dip.

Greg

Maybe John can chime on this if he sees it but personally, if I had the space to angle my walls, I would prefer to use all available space and make the booth as big as possible. I'd then utilize the space to bass trap as much as possible.

That makes sense. The space I have in my basement might allow me to angle without losing much space (as I need to stay at 6ft along the walls to avoid the windows, but could theoretically widen a bit on the sides out if I set it up right). However, if I can't, then maximizing square footage instead of messing with angles and losing a bunch makes a ton of sense.

It does help, for sure. But isolation clips are going to work better.

Gotcha. Any that you suggest?

The GG will help some. Mostly at the coincidence dip.

Hrm. If that's the case, would it make more sense to just straight up double drywall and spend the money on iso clips for the other side instead?

Thanks again!

Unrelated, I'm having a bit of a rough time making a design in sketchup. I can build the one set of parallel walls easily enough, but getting the perpendicular ones to angle perfectly and the pieces to fit exactly right has been causing me a ton of grief. Things don't click in, and I feel like I'm missing something, as I'm trying to tell specific items to move a certain amount of inches (and 1/16 of inches) along specific planes to kind of make it work. Any thoughts? Or specific videos you suggest?

Thanks again!

Matt

Gotcha. Any that you suggest?

I've personally never used them so I can't comment on which would be good or bad. Anyone have any recommendations?

Hrm. If that's the case, would it make more sense to just straight up double drywall and spend the money on iso clips for the other side instead?

That's a decision you should make

Unrelated, I'm having a bit of a rough time making a design in sketchup. I can build the one set of parallel walls easily enough, but getting the perpendicular ones to angle perfectly and the pieces to fit exactly right has been causing me a ton of grief. Things don't click in, and I feel like I'm missing something, as I'm trying to tell specific items to move a certain amount of inches (and 1/16 of inches) along specific planes to kind of make it work. Any thoughts? Or specific videos you suggest?

I believe I went through the same growing pains.

- When you first draw something such as a 2x4 piece of lumber, you're going to start off drawing a rectangle. Make sure you draw it on something you know is flat or at least make sure that your axis are all straight. After that, double click it and make it a component. Then, push/pull it to length.

- Using the rotate tool, you can then rotate any component by simply clicking a corner of it and then clicking another corner of it then rotate it to line up with any other component in your drawing. This is done by moving your cursor to the point you want it to line up with. If something isn't at the right angle, I will move a component such that one of it's corners line up with a corner of an component I want it to line up with. Then, rotate it as I explained above.

- Moving things is best achieved by inferencing your axis. When you click on something and it starts to move, click either your up, left or right arrows on your keyboard to lock it to that axis. Just like rotating, you can simply move a component to a specific spot by clicking on your component once and then moving your cursor to a different component that you want to line it up to. If you have to move something really out to lunch in every direction, it's often best to move the component in 3 separate steps/moves -- one for each axis.

- Basically, I'm saying that inferencing is the backbone of making good models in SketchUp.

- Youtube sketchup inference and watch a bunch of them. The down arrow on your keyboard allows you to inference any line/angle that is in your model and isn't up, left or right. This is great when you're building angled crap like your speaker soffit baffles. Also, if you just hold your cursor over anything for a few seconds it uses that as a inference guide. For circles, hold your cursor over the circumference for a few seconds then move your cursor roughly to the middle of the circle and you can inference the exact middle of a circle.

It sounds like you may have accidentally entered the "edit component" and warped some of your components so they aren't truly square/rectangle anymore? Also, personally, if I'm not working with a component I lock it. Locking your components will prevent you from accidentally moving or editing them. It's rare for me to use groups but there is a time and place for that... kind of. Oh, and instead of making a bunch of components from scratch, practice making "unique" components. When you copy or duplicate a component, simply right click the new one and "make unique". This will allow you to modify the new copied component any way you like without screwing up the original. This really speeds up framing where you want to use a simple 2x4 or whatever and just need a few a bit shorter or longer. Or, even if you want to make a 2x6 out of a 2x4, just copy it, make unique and then push/pull the 2x4 into a 2x6 size. Nice and fast.

Keep at it and you'll be a SketchUp wizard in no time. There are a lot of great youtube tutorials but feel free to ask here if you need any more help with it.

Greg

Thanks for all the help so far Greg. After some growing pains, I put together my first draft of a booth on sketchup. Everything I could think of was in there. The only thing I haven't done yet is put the hypothetical iso clips on all walls (just on the one so far). I left half an inch all around for them though between the frame and drywall. Suggestions and thoughts would be much appreciated. I decided to go with full height bass traps. I'll likely frame them in 2x4 and put 4' rockwool.

I tried uploading it, but it is 605kb and the max upload is 500kb... Any way to bypass that?

In the meantime, here is a link to the sketchup file. Hopefully it works.

https://www.dropbox.com/s/xxncc4d9ozz9v ... 0.skp?dl=0

I decided to go with full height bass traps. I'll likely frame them in 2x4 and put 4' rockwool.

I would build super chunks, not just panel traps.

I tried uploading it, but it is 605kb and the max upload is 500kb... Any way to bypass that?

Unfortunately the upload file size limit can't be bypassed.

For any future SketchUp file uploads, it would be great if you 'file --> save as' in SketchUp and save it as an older version like 2016 as an example. We all use SketchUp Make here because it's free and it stops at 2017. Your file is 2018. I had to upload your file into the 3D Warehouse to convert it so I can open it. I doubt many forum members are going to go through the hassle to open your file.

You need to add some wall studs so that near the corners of your room, you have supports to anchor your clips/drywall to.

You should probably use 2 top plates instead of just 1.

Adjust your door framing to match this: Lastly, you should add some noggins on either side of your door frame.

Looks good! You're now a SketchUp wizard!

Greg

I would build super chunks, not just panel traps.

Would you build up the whole wall? Or just the tops and bottoms then?

Unfortunately the upload file size limit can't be bypassed.

Alas. Linking it is then.

For any future SketchUp file uploads, it would be great if you 'file --> save as' in SketchUp and save it as an older version like 2016 as an example. We all use SketchUp Make here because it's free and it stops at 2017. Your file is 2018. I had to upload your file into the 3D Warehouse to convert it so I can open it. I doubt many forum members are going to go through the hassle to open your file.

Thanks for letting me know. I didn't realize! I saved it as a 2013 file so it can be easily accessed now.

You need to add some wall studs so that near the corners of your room, you have supports to anchor your clips/drywall to.

Done! How do those look?

You should probably use 2 top plates instead of just 1.

Shoot. I was hoping I could get away with one given the low ceiling in the basement already. I might be able to squeeze a second top plate in without needing more height, but it'd be tight.

Adjust your door framing to match this:

how-to-frame-door-rough-opening.jpg

Same with the above issue, I'm worried about shortening the door too significantly. Do you think the setup on the updated file would work? Or at the very least, do you think I could build it without the cripples? and put the 2 2x4 and ply straight onto the top plate?

Lastly, you should add some noggins on either side of your door frame.

Done!

I uploaded the updated version as a skp 2013 file. Hopefully it works more easily this time. Here's the new link: https://www.dropbox.com/s/3q1o4rghhs6ab ... r.skp?dl=0

Thanks again for all the help! I really appreciate it.

Matt

Would you build up the whole wall? Or just the tops and bottoms then?

I would stack triangles of insulation from the floor to ceiling.

Alas. Linking it is then.

Go to "window" then "model info" then "statistic" and "purge unused". This may shrink your file small enough to upload.

Shoot. I was hoping I could get away with one given the low ceiling in the basement already. I might be able to squeeze a second top plate in without needing more height, but it'd be tight.

Just shorten the length of your wall studs by 1.5" to fit the extra top plate.

Same with the above issue, I'm worried about shortening the door too significantly. Do you think the setup on the updated file would work? Or at the very least, do you think I could build it without the cripples? and put the 2 2x4 and ply straight onto the top plate?

If you don't have the space for the cripples then for sure, just put them straight onto the top plates.

uploaded the updated version as a skp 2013 file.

I just downloaded your new linked .skp and here's what I got:

Thanks again for all the help! I really appreciate it.

It might take me a while to get back to everyone but I try my best when I have a few minutes here and there!

Greg

I would stack triangles of insulation from the floor to ceiling.

Great. Thanks!

Go to "window" then "model info" then "statistic" and "purge unused". This may shrink your file small enough to upload.

I will try this. Thanks so much.

Just shorten the length of your wall studs by 1.5" to fit the extra top plate.

Smart. That would maintain height for everything but the door, which would probably be fine at about 6'2 given that I'm 5'8.

If you don't have the space for the cripples then for sure, just put them straight onto the top plates.

Awesome.

I just downloaded your new linked .skp and here's what I got:

Screen Shot 2020-03-02 at 9.14.57 PM.png

Well that's annoying. I'll try and figure it out before I upload the next update.

Thanks again!