some basic help for a newbie

I have just returned to the world of music, I have been away far too long studying and doing far too much other stuff. I am building a vocal recording studio in my basement cellar. I am having trouble understanding if what i'm doing its right, ok or the worst decisions I could be making. The room use to be a cellar but was framed, insulated with fibreglass and drywalled. The walls behind the framing are cement similar to the thickness of the foundation of my house. The room is completely underground. All around it is dirt and above it is the thick slab that makes up my front porch. 1. I will install soundproof double doors. The room is well setup for that. 2. I will install good base traps in the vertices of the room. Just trying to figure out what I can afford. 3. I plan to install wedge acoustic foam on the vertical walls More details: 4. My ceiling height is 81.5" and has a popcorn drywall finish 5. I most likely will wear monitoring headphones and not be installing monitoring speakers at the moment. 6. I don't have a sound level meter yet. When I was recording at a rehearsal studio nearby my vocals in my recordings sometimes hit 0 DBS. I hope that makes sense, I will buy a sound level meter soon. 7. I will be recording classical music (opera similar to Pavarotti and Bocelli). I will be creating recordings that I will be submitting to graduate school for a vocal performance program. Also, recording some pop music for fun. No instrumental recording. Just my vocals. 8. I prefer to keep it under $4,000 but can go more if necessary. 9. No post in the middle of the room. There is a lighting fixture that is dome shaped and looks similar to the picture below. My questions, concerns and worries: 1. Are the dimensions of the room a problem. I hope not too much of a problem. This room is the only place I have to work with. 2. Will the cement walls help with the sound proofing. I understand that the greater the mass of something the more sound it will stop. However I feel that I am missing something. 3. The floor is a thin laminate, on a vapour barrier on concrete. I plan to install carpet tiles. That makes sense. Right? 4. What do I do with the ceiling??? Its not a high ceiling and I don't want to reduce the hight of the room much more. 5. Is this a good product for my purposes? RPG Diffusor Systems: Modex Broadband Would this item help acoustically treat the room effectively? http://www.silentsource.com/diffusors-m ... dband.html This is the top view:(rough but close measurements, a lot of junk needs to be cleared out before I can take exact measurements. The dimension may be off by 1"-3") The Entrance is the dimension of 30 5/8" on the angled portion of my drawing.

Hi there Adam, and welcome! :)

All around it is dirt and above it is the thick slab that makes up my front porch.

Concrete slab?

2. I will install good base traps in the vertices of the room. Just trying to figure out what I can afford.

The very best way of doing that is with the "Superchunk" design, but that might be expensive. Search the forum for that, and you'll find several examples of how people have done it. The next best things is simply to put a full panel of OC-703 diagonally across the corner.

3. I plan to install wedge acoustic foam on the vertical walls

Do you already have the foam? If not, then forget that: proper acoustic foam is expensive, and cheap acoustic foam most likely is not acoustic foam at all, but some other type of foam that looks similar but is next to useless. You can get very similar results much cheaper with common mineral wool and fiberglass insulation, that you find at any building supplier.

5. I most likely will wear monitoring headphones and not be installing monitoring speakers at the moment.

Then you don't need acoustic treatment! :) A control room only needs treatment if it will be used acoustically. In your case, you'll be just using it to keep the wind and the rain out, so no treatment at all is needed. Of course, if you are talking about a live room or tracking room, well, that's a different issue entirely, and yes you do need treatment for that, but that is very different from the way a control room would be treated. You didn't mention which type of room you are building here!.

6. I don't have a sound level meter yet. When I was recording at a rehearsal studio nearby my vocals in my recordings sometimes hit 0 DBS. I hope that makes sense,

Not really! Sound pressure level is measured as dBA, dBC or dBF: There is no dBS. And a level of 0 means that your voice was actually quieter than dead silence in the middle of the desert at midnight with no wind... :) On the other hand, a level of 0 dB seen on the console simply means that the gain structure of the recording chain was set correctly. Depending on the type of console, that might have been 0 dB VU, 0 dBFS, or something similar. But that tells you nothing at all about how loud your voice was: it just tells you that they were recording your voice correctly for an analog console...

7. I will be recording classical music (opera similar to Pavarotti and Bocelli). I will be creating recordings that I will be submitting to graduate school for a vocal performance program. Also, recording some pop music for fun. No instrumental recording. Just my vocals.

OK, so from what you say so far, it seems like this is going to be just a vocal booth. So it will need to be treated as such, not as a control room.

9. No post in the middle of the room. There is a lighting fixture that is dome shaped and looks similar to the picture below.

Great. That's not a problem at all.

1. Are the dimensions of the room a problem. I hope not too much of a problem. This room is the only place I have to work with.

It's rather small, but if that's all you have then it sure is better than nothing! The height is good, but the width and length are rather small. It's going to be a bit claustrophobic in there. And being such a small size, your only real option for vocal recordings is to make it as dead as possible, then add reverb electronically, in the mix. Making it dead means reasonably god recordings, but does make the room a bit unpleasant to be in for long periods. Our ears are not used to dead rooms.

2. Will the cement walls help with the sound proofing. I understand that the greater the mass of something the more sound it will stop. However I feel that I am missing something.

Yes, concrete is pretty good at isolating a room, but the question is also: What are you isolating from/to? Do you want isolation for your voice, so that you don't disturb others in the house while you are singing? Or do you want to isolate external sounds that might interfere with your recordings? If it is the latter, then what sounds are you worried about, specifically? For example, if the room is close to a road, then traffic noise might be a problem. Or perhaps aircraft flying over, rain, wind, thunder, etc. Or maybe house noises, such as phones, people talking / walking, TV, radio, washing machine, etc.

3. The floor is a thin laminate, on a vapour barrier on concrete. I plan to install carpet tiles. That makes sense. Right?

Not really. Leave it as laminate. The general rule in studios is to have a "hard" floor and a "soft" ceiling, since that is what our brains are most accustomed to hearing. Also, carpet has no place in studios as treatment. It does the opposite of what you need, acoustically. So leave the floor as it is, and treat the walls and ceiling accordingly.

4. What do I do with the ceiling??? Its not a high ceiling and I don't want to reduce the hight of the room much more.

If you have enough isolation already, then the easiest would just be to put six inches (15cm) of OC-703 up there, across the entire ceiling. Simple, cheap, and very effective.

5. Is this a good product for my purposes? RPG Diffusor Systems: Modex Broadband Would this item help acoustically treat the room effectively?

Not for your room, no. You don't need diffusion; you need absorption. You need to make the booth acoustically dead, with thick insulation on most of the surfaces, but placed carefully and not over-doing it. The general rule of acoustics is that the smaller a room is, the more treatment it needs. Very small rooms need huge amounts of treatment, and that has to be mostly absorption, since there is no modal support at all for the low end in tiny rooms, and the modal issues are all pushed up to the low mids, which is exactly where your voice is. In your case, the very lowest mode is at 82 Hz, and most of your issues are up in the range 150 Hz to 400 Hz, which is the low end of the male vocal range. Your only hope of making that space usable for recording vocals is to totally kill all frequencies in the low end, while trying not to also kill the high end excessively. You cannot do that with diffusion. Overall, your plan should work: the solution is simply lots of absorption aimed at the lows and low mids, covered in bands of thin reflective materials to keep the highs in the room, to a certain extent. Theoretically you need about 80 sabins of perfect absorption, and since your entire internal surface area of the walls and ceiling is only 120 square feet, you need to cover about two thirds of that with absorption. But it does need to be spread around intelligently, so you can have slightly differing acoustics in different spots, so you can move the mic and your head around as needed for different types of recordings. - Stuart -

The very best way of doing that is with the "Superchunk" design, but that might be expensive. Search the forum for that, and you'll find several examples of how people have done it. The next best things is simply to put a full panel of OC-703 diagonally across the corner.

For the Superchunk bass trap. I can definitely do that. Is the Superchunk bass trap superior to the Auralex bass trap in terms of performance?

Do you already have the foam? If not, then forget that: proper acoustic foam is expensive, and cheap acoustic foam most likely is not acoustic foam at all, but some other type of foam that looks similar but is next to useless. You can get very similar results much cheaper with common mineral wool and fiberglass insulation, that you find at any building supplier

Is mineral wool and fiberglass insulation superior to Auralex 3” or 4” Studiofoam Wedges or 4” Studiofoam Pyramids. I don’t have any of the materials yet.

Then you don't need acoustic treatment! :) A control room only needs treatment if it will be used acoustically. In your case, you'll be just using it to keep the wind and the rain out, so no treatment at all is needed.

This I changed my mind on. I will be installing monitors.

OK, so from what you say so far, it seems like this is going to be just a vocal booth. So it will need to be treated as such, not as a control room.

The room will be only used by me. I will be hitting the record button and singing. Correct me if I am wrong. I believe that would be called a live room. I will also be listening to my recordings in the same room. That is why I changed my mind and will also be installing monitors. So it will also be my control room.

Not really. Leave it as laminate. The general rule in studios is to have a "hard" floor and a "soft" ceiling, since that is what our brains are most accustomed to hearing. Also, carpet has no place in studios as treatment. It does the opposite of what you need, acoustically. So leave the floor as it is, and treat the walls and ceiling accordingly.

Really, I have read that a hard floor will create sound reflections that I don’t want.

Excellent. Some additional questions: 1. Is there any type of wood in particular that absorbs sound more than other types of wood? For example since oak is a harder more dense wood than pine, would oak be better at absorbing sound? 2. I need to bring in fresh air from an adjacent room and vent stale air out of my studio. The air in my house has a good temperature and humidity. So I won't need to do anything to the air. I was looking at this unit to work into my ventilation. Might you have any other suggestions? Better products etc? http://www.pexsupply.com/Fantech-AEV100 ... ts-120-CFM 3. Do you know any websites that include higher end sound proofing materials. For example, better sound proofing gaskets, seals, door sweeps etc.

For the Superchunk bass trap. I can definitely do that. Is the Superchunk bass trap superior to the Auralex bass trap in terms of performance?

Yes. It is superior to pretty much any other design, due to the total amount of absorption and the total dimensions. A full Superchunk is 36" on the diagonal, and runs from floor to ceiling.

Is mineral wool and fiberglass insulation superior to Auralex 3” or 4” Studiofoam Wedges or 4” Studiofoam Pyramids. I don’t have any of the materials yet.

It can be, if done properly: The advantage to sculpted foam is the additional path length of sound wave at low angles of incidence, and the increased surface area. There is also some high-frequency scattering from the sculpted shapes, which might or might not be good for your room. The disadvantage is the cost.

This I changed my mind on. I will be installing monitors.

:yahoo: :thu: Excellent!

The room will be only used by me. I will be hitting the record button and singing. Correct me if I am wrong. I believe that would be called a live room. I will also be listening to my recordings in the same room. That is why I changed my mind and will also be installing monitors. So it will also be my control room.

Many people build their rooms that way, as a combined tracking room and control room, so that's fine.

Really, I have read that a hard floor will create sound reflections that I don’t want.

On the contrary, it creates the reflections that you DO want, and avoids the ones you don't want. It works like this: Your brain is totally accustomed to hearing reflections from the floor in exactly the same way, wherever you go, because your height never changes throughout your entire adult life. Your ears are always the same height above the floor when you are standing, and also the same height when you are seated, no matter where you are on the planet. So your brain knows exactly how to interpret those reflections coming from the floor. But every place you go, your ears are at a DIFFERENT distance from the ceiling above you, and from the walls around you. So wherever you go, your brain gets different signals, that is has learned to ignore as much as possible when trying to figure out acoustic location. So, if your floor is soft and non-reflective then the reflections that will be in your recordings will be ONLY those that come from other surfaces. And since your brain has no visual clues when listening to a recording, it will assume that the only acoustic clues it is getting are from the floor.... In other words, your perception of sound will not be correct or accurate, and the recording will sound a bit strange, if the main reflections are not coming from the floor. To convince yourself of this take a look at a few dozen photos of world-class studios, such as the ones you see in John's own section of this forum ( http://www.johnlsayers.com ) or the ones you see in magazines or videos of well-known musicians recording their albums in major studios, or the web sites of other well-known studio designers, or even on the forum itself. How many of those pro-level studios have carpet on the floor? :) The number is about zero... So anyone telling you that you should carpet your studio has a fundamental misunderstanding of acoustics in general, and studio design in particular. Carpet does have some very limited applications in studios, but even then it is proper acoustic carpet, not typical commercial carpet, which is a very different thing. - Stuart -

1. Is there any type of wood in particular that absorbs sound more than other types of wood? For example since oak is a harder more dense wood than pine, would oak be better at absorbing sound?

There are slight differences, but nothing worth writing home about. It's all about the density of the wood, and the flexibility to a certain extent.

2. I need to bring in fresh air from an adjacent room and vent stale air out of my studio. The air in my house has a good temperature and humidity. So I won't need to do anything to the air.

So you already have an HVAC system in your house, and you plan to link your room to that? Is that the plan?

I was looking at this unit to work into my ventilation. Might you have any other suggestions? Better products etc?

That's a heat exchanger. It does not silence, cool, or dehumidify, so it would not be a lot of use. What studios need is a constant supply of fresh air from the outside world (not from the next room: that's illegal in many places), a constant return of the same volume of stale air to the outside world, and a method for cooling, dehumidifying, and recirculating the air inside the room itself. The cheapest way of doing that is with a mini-split system to handle the cooling and dehumidifying, and a carefully calculated ventilation system to handle the air movement (fresh/stale). The ventilation system is done with silencer boxes, ducts and fans, and they all have to be sized correctly for the room and occupancy. Or if your the existing HVAC system in the house can handle the extra load, then you can probably skip the mini-split, and just do the ventilation part.

3. Do you know any websites that include higher end sound proofing materials. For example, better sound proofing gaskets, seals, door sweeps etc.

For door seals, the best is Zero International: But those are not "soundproofing materials". They are just seals, which is only a part of "soundproofing". In fact, we don't use the term "soundproofing" much, since there is no technical definition for it, and it means different things to different people. True "soundproofing" is, in fact, impossible. Any sufficiently load sound will penetrate any conceivable barrier that man can build. So we tend to talk about "isolation" and "transmission loss", which are defined terms and mean very specific things. What you need to do is to "isolate" your room to a certain level of "transmission loss". You do that with massive, rigid, thick, dense building materials arranged in specif patterns, and then you add seals (such as those made by Zero International) around doors, so they can provide that same level of isolation. - Stuart -

Alright I am good to go. I started working about a month ago. Its tough balancing this project and a full time job but its going really well. My ventilation decision was to hook it up to the house HVAC. I also added this unit to the house HVAC. I don't mind spending the extra money for the house and this unit can run 24/7 giving me a constant supply of fresh air. http://www.venmar.ca/92-air-exchangers- ... -only.html Thanks for the help soundman. There are very few people who help me with anything in life and for a complete stranger to do so is amazing. To offer real, well thought out advice is more than i get from my friends and family. Cheers and I will send some pictures over soon.

I was just rereading all of your advice to make sure I did not miss anything. Could you elaborate on what you meant by "the solution is simply lots of absorption aimed at the lows and low mids, covered in bands of thin reflective materials" Specifically "covered in bands of thin reflective materials"

Specifically "covered in bands of thin reflective materials"

The actual material depends on the room acoustics, but it could be anything from very thin plastic foil (about the thickness of cheap garbage bags), to thicker plastic sheeting (such as the type used for vapor barriers in houses), or even thin wood (3mm plywood, for example). It might even be some form of diffuser. The final decision on what to do there should wait until you have the room mostly completed with the basic treatment in place, then test it with REW to see how it is behaving, and choose your material based on that. - Stuart -

Got it. Thanks :D

*** start from the bottom of this post. Pics and update. I really wish I had taken more pics. A lot of the ventilation I already closed up in drywall. Too bad :(

Continued. *** start from the bottom

Quick summary of whats next. - I will be installing double doors. I placed an order for all my headers, jambs and door bottoms from zero international. - I definitely got the good stuff and am just waiting for them to make and ship it. - I need some acoustic treatment for mid frequency which I will figure out soon. - I need to decide how I want my doors to close and lock - I need to finish the desk which I will put my laptop and monitors on - The room outside I am going to turn into a bigger office with lots of storage and a big desk. In the future this room could be a control room. I did run some tubing in the wall and blank boxes in case I want to run some wires.

All of the above stuff is done. It went really well. I did take some pics but sizes and dimensions are too big. I will edit them soon. Next questions: The bands of thin plastic that I need to use to reflect the high frequency sound: 1) Do those need to go on top of my current acoustic panels and super chunk bass traps or can they go on the walls? I am having trouble choosing a specific product or type of plastic. 2) Would really thin sheet metal work? 3) Would thin pieces of acrylic plastic work? 4) Would nicely cut pieces of construction garbage bags work?

1) Do those need to go on top of my current acoustic panels and super chunk bass traps or can they go on the walls?

They go between the insulation itself, and the fabric that covers it. Use it only in the places where you DO want to reflect mid- and high- frequencies back into the room: So not on first reflection points, for example, but yes on bass traps.

2) Would really thin sheet metal work? 3) Would thin pieces of acrylic plastic work? 4) Would nicely cut pieces of construction garbage bags work?

All of those would work, but each one for a different frequency range. The thicker the membrane is, the lower it will go in reflecting sound. Very thin plastic (like garbage bags) will only reflect very high frequencies. Sheet metal will probably reflect way down as far as the low mids. so you use whatever material you need to use, to reflect the frequencies that are already over-absorbed in your room. - Stuart -