Building my first real home studio!

Ryan

Senior Member
Hi all,

I've been away from this forum for some time now. :)

I have been so fortunate to get the opportunity to build my own little studio in my house. The reason for this is that we had to enlarge our house a bit because of the kids. So, in this case I had the chance to build a fitting room for my needs at the same time.

The control room will be around 8,3 M2, and my living room would be used as a recording space (smaller groups or solo instruments). Over the past year I've been planning it out with our contractor. My main goal was soundproofing it as good as possible from the rest of the house. This because I have small kids. After some planning with the contractor we decided to float the concrete so it is totally isolated from the rest of the house. He also suggested to build the walls separated from each other.

So, here comes the questions: Acoustic treatment and bass-traps. I don't want the room to get to "pimped" with treatment. I want it to be a calm and creative place to be in. What are my options regarding acoustic treatment?
PS: monitors are a pair of PSI Audio A17-M.

Wire in all my gear.. Patchbay (hallelujah). I got a vintage analog console that I use nearly on a daily basis. I often route my stuff trough it and into compressors, eq, effects etc. What are the best patchbays to get? the easiest to setup etc. Soundcards RME adi-8 DSmk2 and digiface etc. You get the idea.
That mixer also got some of the best preamps one may get, so I should maybe get a XLR patchbay to easy navigate to my mic inputs on demand?

I will most likely ask more question down the road.

For the ones who are interested in some picture of the building process. In that first picture (picture taken May) you could see the yellow insulation to the right where the concrete gets isolated from the rest of the building. Make sure to follow me for updates on the build :)


Best
Ryan
 
Last edited:

mc_deli

n trepreneur
Ahh, Thanks for the heads up.
Have you spent some time on the John Sayers forum? It is an amazing place to learn about details and have your plans dissected.

The pic looks like you have an extension or add-on to the house, which seems a bit odd with then a "floated" concrete floor (which usually means springs or similar). You are obviously spending a lot of money. I hope your your contractor is experienced. Good luck. Sounds exciting.
 

Pier Bover

Active Member
I'm no expert but here is a little intro.

First it's a good idea to buy a calibrated mic. There are decent ones for as little as $20 (see this one). A good one is not too expensive either but it might not make sense if you are not doing this professionally. Get the software RoomEQ Wizard which is free and easy to use.

Ideally you should have non parallel walls/floor/ceiling to reduce low frequency modes. Hopefully you did take that into account before building because otherwise LF are difficult to tame and generally speaking are very difficult to fix with just absorption.

For small room treatment you have 2 options: absorption and diffusion. As how you much you want of each is a difficult thing to say. You should probably do it gradually until you are happy with the sound, or pay an expert :P

Absorption is basically porous materials that reduce the energy of the waves every time they go through it and bounce through the room. You do not want your room to be completely dead by putting too much absorption. To use absorption for LF you need a lot of fluffy material (rock wool, glass fibers, etc) and also leave a gap between the material and the wall. The idea is that absorption works best when the wave is at max velocity which is 1/4 of the wavelength (instead of max pressure which is when the wave hits the wall and bounces). For MF and HF the wavelength is very small, but for LF it can be many feet. This is why usually LF absorption (bass traps) are put on the corners in an angle, to get maximum practical distance between the absorber and the wall. This is also why it's simply not practical to get absorption at very LF. For example, at 80Hz the wavelength is about 4 meters, so you'd need 1 meter (3.3 feet) of space, and it gets bigger the lower the frequency (for 20Hz I believe it's about 17 meters).

1575431890012.png

1575431925822.png

As for the absorption material, usually DIYers use Owens Corning 703. You could buy different materials for different purposes. Look at charts for absorption coeffcients.

I built some absorbers a couple of months ago for my home studio. You can check the build and more info here.

Diffusion is when the waves are scattered in different directions. Experts argue real diffusion only occurs when the scattering is equal on all frequencies. So adding random shapes in the room is not really diffusion. Diffusion helps scatter the waves which also reduces the modes. It also confuses our brains and it appears the room is bigger that it really is. The most predictable diffusers are quadratic diffusers.

Diffusion works great for HF and MF, but at LF it's impractical to use diffusion as it would mean you'd lose a lot of space as the diffusers would be huge (again because of the wavelength).

Anyway, once you have figured out the best listening postion you have to position the speakers and the furniture and measure the room with REW. You can also move around the room clapping and listening for any anomalies (metallic reverbs, flutters, small echoes, etc). With the measurements and the clapping you will have a general idea of what problems you need to fix.

I'm sure an expert would laugh at this info and pedestrian methods... but that's the DIY empirical way.

Don't hesitate to ask!
 
Last edited:

wst3

my office these days
Moderator
ask away!

I designed studios for a while, back when one could make an honest living at it. I also maintained consoles and tape decks. These are, at least where I live, lost arts. I am not bragging (far from it) just trying to establish a baseline. My opinions may well be dated, but they are based on more years in the industry than I will admit. These days I design conference rooms and classrooms, and frankly, the interest in audio continues to wane. I will never understand why.

Soundproofing and acoustical treatment are two very different disciplines, although they do interact. You are wise to start with soundproofing, especially since this is your home.

Mass is the best way to block sound, but mass alone won't do it, you need to block all possible paths, and some of them will fool you. So build massive walls, and keep them as air tight as you can. The best construction is mass-spring-mass, so two walls separated by an air gap is king. While it is counter-intuitive, three walls with two air gaps will degrade your isolation.

The use of two layers of dissimilar materials is a great way to increase isolation. I use two different depths of sheetrock glued together with overlapping seams. If I can't take advantage of a block wall then I will build both walls this way.

The floor and ceiling will prove to be the most complex problem. If you are building on grade then that problem goes away, if you are building above another space you will need to plan accordingly. Floating the floor is not as expensive as you might think.

The ceiling - if there is living space above you then consider suspending a second ceiling, or isolating it completely by attaching it to your inner walls only. I've tried both, and had decent results with both. In one case the family room was above the studio, so we ended up building up the family room floor as well.

If you have windows you will need to use double-pane models, and accept that unless you spend an insane amount they will be your weakest link. Also pay attention to doors, although it is easier (and cheaper) to get them right.

Now is also the time to plan your HVAC system - a separate system is best, a separate, lined duct that takes the long way around is pretty darned good. Split systems have dropped in price and could be a good solution too.

Nothing worse than building a soundproof room and then killing it with a penetration. Plan all your cable paths that cross the boundaries now. Make them mazes if you have to. This includes power, don't forget power.

Which brings us to the acoustical treatment. You want your control room to be natural and neutral at the same time. Good luck. There are many philosophies for the design of critical listening spaces. Learn about them, and pick one. I don't believe there are any real turkeys left, but the designs that survived will sound different.

Do NOT go overboard on absorption, and don't fall prey to the myth that is provides isolation, it doesn't. You have three arrows in your quiver - absorption, reflection, and diffusion, use all three. Learn about the Haas effect, and then design things to keep reflections in the best temporal sequence you can. If you have the luxury of playing with room geometry by all means do so!

Low frequency modes, or standing waves, are a problem. You can not make them go away in any reasonably sized room. So you treat them. Start with broadband absorption and resort to tuned absorbption only if you have to.

This is where I'll suggest hiring an acoustician - the cost of a good measurement microphone is still pretty high, and sorry, those $20 models are not reliable, not even "reliable enough". Rent or buy a decent measurement microphone. The software is much more reasonable. I prefer StudioSix Digital, but there are other packages that work well. The trick is learning to read the reports. Again, this is a good time to hire an acosutician.

By no means should you read that to suggest that I am anything less than 100% in favor of musicians building their own studios. DIY means you can make changes when you need to, and you'll understand how.

Aside - when I was running a business to maintain studios I taught my clients to align their tape decks, and entire systems, and helped them purchase the test equipment they needed to do the job. By learning to take care of the basics themselves they increased their ability to deliver a great product. I still came by regularly to check things out, but they were not dependent on me for basic maintenance. Maybe not the best business decision, but it felt right.

Power and grounding could fill another volume, and my fingers are getting tired.

So too is interconnection - especially today with a mix of single-ended and balanced connections. I will suggest that you choose patchbays wisely, and they can be the single biggest source of problems in the studio. Keep the number of connectors to a minimum, and no NOT use patchbays with 1/4" connectors on the front and rear. While easier to repair, you will spend a lot more time repairing them. If you do not want to spend hours soldering choose a patchbay with Elco/Edac or similar connectors on the rear. If space is a premium consider TT or Bantam patchbays, otherwise save your money and just use 1/4" TRS patchbays.

What else - I didn't touch on lighting or ergonomics, but you probably aren't quite there yet?

Above all else, have fun, and learn a lot.
 

Pier Bover

Active Member
the cost of a good measurement microphone is still pretty high, and sorry, those $20 models are not reliable, not even "reliable enough"
I agree given enough budget it would be better to hire an expert, but I think you might be losing context here.

We are not talking about a reference mixing room. The difference between an Earthworks mic and a cheap $40 Behringer one is negligible for this context.

See these measurements by Ethan Winer.

What good is a microphone that will deliver absolute precision when even in the best treated home studios there will be easily peaks and valleys of more than 5dbs at the listening position? It will be even more drastic when moving just a couple of feet from the listening position.
 

wst3

my office these days
Moderator
I will stand by my comments - there are decent measurement microphones for far less than the Earthworks, and they will be a better choice than any $40 microphone.
 
OP
Ryan

Ryan

Senior Member
ask away!

I designed studios for a while, back when one could make an honest living at it. I also maintained consoles and tape decks. These are, at least where I live, lost arts. I am not bragging (far from it) just trying to establish a baseline. My opinions may well be dated, but they are based on more years in the industry than I will admit. These days I design conference rooms and classrooms, and frankly, the interest in audio continues to wane. I will never understand why.

Soundproofing and acoustical treatment are two very different disciplines, although they do interact. You are wise to start with soundproofing, especially since this is your home.

Mass is the best way to block sound, but mass alone won't do it, you need to block all possible paths, and some of them will fool you. So build massive walls, and keep them as air tight as you can. The best construction is mass-spring-mass, so two walls separated by an air gap is king. While it is counter-intuitive, three walls with two air gaps will degrade your isolation.

The use of two layers of dissimilar materials is a great way to increase isolation. I use two different depths of sheetrock glued together with overlapping seams. If I can't take advantage of a block wall then I will build both walls this way.

The floor and ceiling will prove to be the most complex problem. If you are building on grade then that problem goes away, if you are building above another space you will need to plan accordingly. Floating the floor is not as expensive as you might think.

The ceiling - if there is living space above you then consider suspending a second ceiling, or isolating it completely by attaching it to your inner walls only. I've tried both, and had decent results with both. In one case the family room was above the studio, so we ended up building up the family room floor as well.

If you have windows you will need to use double-pane models, and accept that unless you spend an insane amount they will be your weakest link. Also pay attention to doors, although it is easier (and cheaper) to get them right.

Now is also the time to plan your HVAC system - a separate system is best, a separate, lined duct that takes the long way around is pretty darned good. Split systems have dropped in price and could be a good solution too.

Nothing worse than building a soundproof room and then killing it with a penetration. Plan all your cable paths that cross the boundaries now. Make them mazes if you have to. This includes power, don't forget power.

Which brings us to the acoustical treatment. You want your control room to be natural and neutral at the same time. Good luck. There are many philosophies for the design of critical listening spaces. Learn about them, and pick one. I don't believe there are any real turkeys left, but the designs that survived will sound different.

Do NOT go overboard on absorption, and don't fall prey to the myth that is provides isolation, it doesn't. You have three arrows in your quiver - absorption, reflection, and diffusion, use all three. Learn about the Haas effect, and then design things to keep reflections in the best temporal sequence you can. If you have the luxury of playing with room geometry by all means do so!

Low frequency modes, or standing waves, are a problem. You can not make them go away in any reasonably sized room. So you treat them. Start with broadband absorption and resort to tuned absorbption only if you have to.

This is where I'll suggest hiring an acoustician - the cost of a good measurement microphone is still pretty high, and sorry, those $20 models are not reliable, not even "reliable enough". Rent or buy a decent measurement microphone. The software is much more reasonable. I prefer StudioSix Digital, but there are other packages that work well. The trick is learning to read the reports. Again, this is a good time to hire an acosutician.

By no means should you read that to suggest that I am anything less than 100% in favor of musicians building their own studios. DIY means you can make changes when you need to, and you'll understand how.

Aside - when I was running a business to maintain studios I taught my clients to align their tape decks, and entire systems, and helped them purchase the test equipment they needed to do the job. By learning to take care of the basics themselves they increased their ability to deliver a great product. I still came by regularly to check things out, but they were not dependent on me for basic maintenance. Maybe not the best business decision, but it felt right.

Power and grounding could fill another volume, and my fingers are getting tired.

So too is interconnection - especially today with a mix of single-ended and balanced connections. I will suggest that you choose patchbays wisely, and they can be the single biggest source of problems in the studio. Keep the number of connectors to a minimum, and no NOT use patchbays with 1/4" connectors on the front and rear. While easier to repair, you will spend a lot more time repairing them. If you do not want to spend hours soldering choose a patchbay with Elco/Edac or similar connectors on the rear. If space is a premium consider TT or Bantam patchbays, otherwise save your money and just use 1/4" TRS patchbays.

What else - I didn't touch on lighting or ergonomics, but you probably aren't quite there yet?

Above all else, have fun, and learn a lot.
WOW! So much great information here.

I start with this> "so two walls separated by an air gap is king". Check. I made sure that the contractor built two separate inner walls on each side of the "insulation" in the concrete. The walls are not with sheetrock but two layers of drywalls. That would give the walls some more mass.

The build is on the grade. No rooms over or under.
Regarding the floating of the floor: The contractor said it didn't cost me anything more to do it. They were still going to fill it with concrete, so setting up the "floating" was not that big of a job.

The windows are regular 3-layer glass, but they will not be facing any bedrooms etc. So, I hope that would work just OK.

HVAC system: That one I skipped due to the costs.

All the cable paths goes inside the walls. I planned it out with the electrician. All of the "holes" are filled with acrylic sealant. And non of the holes are on the wall facing the rest of the house. I also got the electrician to add a new fuse just for that room.

I'm thinking of hiring an acosutician to do some of the "tuning".

Regarding the patchbay. I would only get a bantam-bay.. They seem so much better then the 1/4" connectors. For me the big question is if I should take a bantam-patchbay with DSUB, or the elco/edac etc. I know some of the manufactures have the possibility to choose whether you need FN, HN or NN on the inside of the unit. I would most likely need to do a lot more googling on that topic.

Not quite there yet with the ergonomics and lights.

Yes, this is a lot of fun!

Ryan
 
OP
Ryan

Ryan

Senior Member
I'm no expert but here is a little intro.

First it's a good idea to buy a calibrated mic. There are decent ones for as little as $20 (see this one). A good one is not too expensive either but it might not make sense if you are not doing this professionally. Get the software RoomEQ Wizard which is free and easy to use.

Ideally you should have non parallel walls/floor/ceiling to reduce low frequency modes. Hopefully you did take that into account before building because otherwise LF are difficult to tame and generally speaking are very difficult to fix with just absorption.

For small room treatment you have 2 options: absorption and diffusion. As how you much you want of each is a difficult thing to say. You should probably do it gradually until you are happy with the sound, or pay an expert :P

Absorption is basically porous materials that reduce the energy of the waves every time they go through it and bounce through the room. You do not want your room to be completely dead by putting too much absorption. To use absorption for LF you need a lot of fluffy material (rock wool, glass fibers, etc) and also leave a gap between the material and the wall. The idea is that absorption works best when the wave is at max velocity which is 1/4 of the wavelength (instead of max pressure which is when the wave hits the wall and bounces). For MF and HF the wavelength is very small, but for LF it can be many feet. This is why usually LF absorption (bass traps) are put on the corners in an angle, to get maximum practical distance between the absorber and the wall. This is also why it's simply not practical to get absorption at very LF. For example, at 80Hz the wavelength is about 4 meters, so you'd need 1 meter (3.3 feet) of space, and it gets bigger the lower the frequency (for 20Hz I believe it's about 17 meters).

View attachment 24988

View attachment 24989

As for the absorption material, usually DIYers use Owens Corning 703. You could buy different materials for different purposes. Look at charts for absorption coeffcients.

I built some absorbers a couple of months ago for my home studio. You can check the build and more info here.

Diffusion is when the waves are scattered in different directions. Experts argue real diffusion only occurs when the scattering is equal on all frequencies. So adding random shapes in the room is not really diffusion. Diffusion helps scatter the waves which also reduces the modes. It also confuses our brains and it appears the room is bigger that it really is. The most predictable diffusers are quadratic diffusers.

Diffusion works great for HF and MF, but at LF it's impractical to use diffusion as it would mean you'd lose a lot of space as the diffusers would be huge (again because of the wavelength).

Anyway, once you have figured out the best listening postion you have to position the speakers and the furniture and measure the room with REW. You can also move around the room clapping and listening for any anomalies (metallic reverbs, flutters, small echoes, etc). With the measurements and the clapping you will have a general idea of what problems you need to fix.

I'm sure an expert would laugh at this info and pedestrian methods... but that's the DIY empirical way.

Don't hesitate to ask!
Hi,
So much information! :)
I did take some of the parallels, regarding walls, ceiling into consider when planning it with the architect. I decided to have the ceiling in a 10 degrees angle, the highest point in the room is at 2.60.meters, and the lowest is at 2.20M

What I'm most worried about is the bass/lows and how to threat them rightly. I got some diffusion I plan to use inside the room from Vicoustics. Should I treat the ceiling with some diffusion too? Or does the angle do the trick?

I will most likely try out the microphone and the program/software first. But most likely I would fail, and then call for backup/help :D
 

wst3

my office these days
Moderator
sounds like things are going quite well! Just a couple random thoughts...

If you can run the entire studio from a single breaker or fuse that's great, if not consider asking the electrician to install a sub-panel just for the studio. Clean power, and especially a clean ground are a huge help.

I agree on Bantam, they are better, but also more expensive. There are a couple companies that make a patchbay that uses smaller Elco/Edac connectors, one per jack, and also allow you to normal things as needed. These look a little like the dreaded Molex, but they are blades, not cylinders, and they have been very reliable. I get mine from Audio Accessories, they may not be the cheapest, but they are very good.

Next you will want to read all you can about connecting gear. There are maybe three or four authors that you can trust. Neil Muncy came up with the authoritative paper on the topic, but it may only be available to AES members. Bill Whitlock is his appointed successor, and his papers are available at Jensen Transformers and all over the net. Jim Brown is another trusted authority on the topic. and finally Steve Macatee wrote the definitive cookbook, Rane Note #110, which is probably still available from Rane.

Stick with these guys and you will have a very quiet studio.

Enjoy!
 
OP
Ryan

Ryan

Senior Member
Have you spent some time on the John Sayers forum? It is an amazing place to learn about details and have your plans dissected.

The pic looks like you have an extension or add-on to the house, which seems a bit odd with then a "floated" concrete floor (which usually means springs or similar). You are obviously spending a lot of money. I hope your your contractor is experienced. Good luck. Sounds exciting.
I did it to get it totally separated from the rest. It didn't cost me more. :)

I'll check out that John Sayers forum!
 
OP
Ryan

Ryan

Senior Member
sounds like things are going quite well! Just a couple random thoughts...

If you can run the entire studio from a single breaker or fuse that's great, if not consider asking the electrician to install a sub-panel just for the studio. Clean power, and especially a clean ground are a huge help.

I agree on Bantam, they are better, but also more expensive. There are a couple companies that make a patchbay that uses smaller Elco/Edac connectors, one per jack, and also allow you to normal things as needed. These look a little like the dreaded Molex, but they are blades, not cylinders, and they have been very reliable. I get mine from Audio Accessories, they may not be the cheapest, but they are very good.

Next you will want to read all you can about connecting gear. There are maybe three or four authors that you can trust. Neil Muncy came up with the authoritative paper on the topic, but it may only be available to AES members. Bill Whitlock is his appointed successor, and his papers are available at Jensen Transformers and all over the net. Jim Brown is another trusted authority on the topic. and finally Steve Macatee wrote the definitive cookbook, Rane Note #110, which is probably still available from Rane.

Stick with these guys and you will have a very quiet studio.

Enjoy!
I'll ask if that's doable next time I see him.

Great information on the Bantams, I'll check out the names and papers :)

Thank you once more! Much appreciated.
 

wst3

my office these days
Moderator
I did take some of the parallels, regarding walls, ceiling into consider when planning it with the architect. I decided to have the ceiling in a 10 degrees angle, the highest point in the room is at 2.60.meters, and the lowest is at 2.20M
That may not be enough to solve the problem, but it can't hurt. The only disadvantage to angling the walls and ceiling is that you can no longer calculate modes reliably. You need finite element analysis - which is way beyond me.

Ryan said:
What I'm most worried about is the bass/lows and how to threat them rightly. I got some diffusion I plan to use inside the room from Vicoustics. Should I treat the ceiling with some diffusion too? Or does the angle do the trick?
Diffusion is probably not going to do much - you need to think in terms of wavelength, not frequency.

To get an idea of scale let's look at ISO 1/3 Octave Centers:

20.0 Hz 56.50 ft
25.0 Hz 45.20 ft
31.5 Hz 35.88 ft
40.0 Hz 28.25 ft
50.0 Hz 22.60 ft
63.0 Hz 17.94 ft
80.0 Hz 14.13 ft
100.0 Hz 11.30 ft
125.0 Hz 8.97 ft
160.0 Hz 7.06 ft
200.0 Hz 5.65 ft
250.0 Hz 4.48 ft
315.0 Hz 3.53 ft
400.0 Hz 2.83 ft
500.0 Hz 2.24 ft

(apologies for using Imperial measurements)

But you can see that a diffusor would have to be VERY large to affect energy even at 500 Hz.

To manage (you don't really control) the room modes you need to use absorption and reflection, and again the scale of the absorber is problematic. Look into a device called the Tube Trap. I no longer remember why they work, but they do, they are not snake oil. And they still won't solve the problem but they can help.

Ryan said:
I will most likely try out the microphone and the program/software first. But most likely I would fail, and then call for backup/help
It isn't about failing, or succeeding! It is about getting as far as you can on your own, and then inviting someone with more experience to help you get further. That is an important distinction.
 

Rex282

Active Member
I didnt want to go with the supermarket room treatment so I made my own vg.jpguni.jpgdv.jpgdali.jpginspiration from the masters.
 
Last edited:

Nick Batzdorf

Moderator
Moderator
By the way, the first thing I'd think about if I were building from the ground up is the ratios - something I know not even enough about to be dangerous, but at the most basic level you want to avoid having dimensions that... I forget the term! But for example 8 x 12 x 16 is going to be a problem.

What is the term? I guess it's a common denominator, but that's not what I'm searching my brain for. It's been a very long time...
 

mc_deli

n trepreneur
WOW! So much great information here.

I start with this> "so two walls separated by an air gap is king". Check. I made sure that the contractor built two separate inner walls on each side of the "insulation" in the concrete. The walls are not with sheetrock but two layers of drywalls. That would give the walls some more mass.

The build is on the grade. No rooms over or under.
Regarding the floating of the floor: The contractor said it didn't cost me anything more to do it. They were still going to fill it with concrete, so setting up the "floating" was not that big of a job.

The windows are regular 3-layer glass, but they will not be facing any bedrooms etc. So, I hope that would work just OK.

HVAC system: That one I skipped due to the costs.

All the cable paths goes inside the walls. I planned it out with the electrician. All of the "holes" are filled with acrylic sealant. And non of the holes are on the wall facing the rest of the house. I also got the electrician to add a new fuse just for that room.

I'm thinking of hiring an acosutician to do some of the "tuning".

Regarding the patchbay. I would only get a bantam-bay.. They seem so much better then the 1/4" connectors. For me the big question is if I should take a bantam-patchbay with DSUB, or the elco/edac etc. I know some of the manufactures have the possibility to choose whether you need FN, HN or NN on the inside of the unit. I would most likely need to do a lot more googling on that topic.

Not quite there yet with the ergonomics and lights.

Yes, this is a lot of fun!

Ryan
I am very excited for you. I’ve been through a commercial build once and it was a fantastic experience.

I’m not an expert. However, I’ve spent far too much time on John Sayers’ forum and with the literature.

There are a few alarm bells in what you have said on here. A floating concrete floor is expensive. Therefore it’s probably not a floating concrete floor. If you spend 50, 100, 150k on a studio and don’t install HVAC it suggests you don’t have expert advice or a sound plan. “You made sure” they built two walls... but are they actually isolated from each other, what construction was used... and your studio will only be as soundproof as your windows and doors.

If your inner/outer leaves (walls and ceiling) are not decoupled and sealed properly you are burning money.

There are a few nightmare scenario threads on John Sayers and your posts here remind me too much of those. I hope that your build is water tight and it’s just getting lost in translation...

but I beg you... spend a few hours writing an intro post on John Sayers now and get some expert feedback:)
 

mc_deli

n trepreneur
By the way, the first thing I'd think about if I were building from the ground up is the ratios - something I know not even enough about to be dangerous, but at the most basic level you want to avoid having dimensions that... I forget the term! But for example 8 x 12 x 16 is going to be a problem.

What is the term? I guess it's a common denominator, but that's not what I'm searching my brain for. It's been a very long time...
There are a room mode, reverb time and transmission loss (material use) calculators on the John Sayers forum.

And a good piece about triple leaf here: https://www.soundproofingcompany.com/soundproofing_101/triple-leaf-effect