Soundproof Your Studio

FREE Soundproofing Workshop: https://www.soundproofyourstudio.com/workshop

This is the final installment of a soundproof studio built inside a prefabricated shed here in Nashville. There are two other videos that document the entire build. You can watch all of them at this link - https://www.youtube.com/playlist?list=PLZ5pr-thcSKymQJ80Vg4Y1hkJf_9_Zkcv

FREE Soundproofing Budget Calculator: https://www.soundproofyourstudio.com/calculator

If you are soundproofing a room one of the first questions you will ask yourself is how much will it cost. Unlike traditional construction, soundproofing requires some extra costs. I have a soundproof budget calculator that can help you figure out your soundproof room budget based on square footage or square meters. 

You can download the free soundproof budget calculator at this link: https://www.soundproofyourstudio.com/calculator

The most important factor in building a soundproof room is the size. If you only have $10,000 than you will only be able to build a 100 sq/ft room. So, if you have a really tight budget your best bet is to compromise on space. I know...not what you wanted to hear. 

Regular construction say for a remodel in a home according to Forbes is $140 per sq/ft. (Bartolone) Soundproofing averages closer to $180 per square foot for new construction and $105 for an existing structure. 

Some of the construction costs are the same. You will need lumber for framing, nails, screws, drywall, electrical, heating and cooling, paint, trim, you get the picture. However, some costs are soundproof specific. These are things like:

These costs can add up and lead to a higher dollar amount on average per square foot for your build. 

Many people want to build a soundproof room in an existing structure like a basement or a garage. In this example we will have a 200 square foot room. If we type 200 into my soundproof calculator here is what you get: 

For ease of teaching, I only included one door in this example and there is not a window. You can add the square footage of any windows in your room and get an added cost. 

We can see in the right hand side, the the black box is for a studio built in an existing structure. I removed some of the costs for ground up build to give you a more accurate estimate. This includes: 

We see that our total studio cost could be around $15,692.34. With a 20% buffer (which I highly recommend) you are looking at $18,830.81. 

Now is when you say you could do it for cheaper. That is totally fair. These were my costs and I surely may have paid too much in some areas. The labor includes paying my contractor $40/hour and occasionally some other labor at $15-25 per hour. So if you don't do any work yourself I guarantee it will cost more. 

I worked alongside my contractor on the entire project and did not pay myself so keep that in mind. 

Soundproofing a room correctly is not the cheapest endeavor. I created this calculator to give you a gut check before you build. My contractor had never built a studio before and he estimated we could build it for $20-25K dollars. In the end it costed closer to $48,000 when it was all said and done. Yeah...that one hurt a bit. 

I don't want that for you, so take my calculator seriously and then do your own research on costs before you dive in. Don't let a contractor with no soundproof construction experience say they can do it for less, because either they will do it wrong or have you on the line for way more money than anticipated. 

Just my words of wisdom from someone who has built and designed 5 soundproof projects and is always working on more. 

Works Cited:

Bartolone, Ginny. “How Much Do Home Additions Cost in 2023?” Forbes, Forbes Magazine, 30 May 2023, www.forbes.com/home-improvement/home/home-additions-cost/.

FREE Soundproofing Workshop: https://www.soundproofyourstudio.com/workshop

Many people come to me saying they will use Rockwool to soundproof their walls. First, this is not really necessary. Second, if you build a normal wall with Rockwool it will only marginally improve the sound isolation. In this article I will argue why the cheapest insulation that provides adequate climate control for your location is the best choice for your wall. 

When we build a soundproof wall it is soundproof because of the sum of its parts, not a single material. Many people believe that adding Rockwool, which boasts enhanced acoustic properties will help improve the STC rating on their wall. The truth is that is will mostly hurt your wallet without adding any noticeable change in sound isolation. 

Below is a diagram of several different wall designs. 

Notice that the wall to the far right has the best sound isolation. This is due to the wall construction not the individual parts. To prove this interesting point, the wall the third from the left has an STC of 40. This involves the same 4 layers of drywall, wood studs, and insulation, however by moving the drywall to the two outside walls and leaving an airspace in the middle the STC rating improves by 23 points! 

My point is that the insulation is important, but not a huge game changer when it comes to soundproofing. What matters most is having some form of fiberglass insulation in the wall and building it the correct way so that you have a mass spring mass system. 

So the first thing that we need to do when properly insulating our walls regardless of soundproofing is to get the right R Value for our climate. Below is a chart for the USA for different recommended R Values depending on the region you are building in. Now this would be important for a stand alone structure build in your backyard, roof insulation, or any wall that touches the outside of your home or garage. 

For example, my studio needs insulation on all walls and in the ceiling for walls that touch that outside. According to this chart, I could use R38 in my attic and R13 to R15 in my walls. We actually used R30 insulation for my entire studio build, so be sure to confirm with your contractor what is best for your specific build. 

The key point is that Safe N Sound is meant for interior wall construction only and does not have a tested R Value. This means is is created for sound control, but not holding in heat and air conditioning. 

This is a huge flaw for many builds and is one reason I don't recommend Rockwool Safe N Sound to my soundproofing clients. 

The truth is that Rockwool is more expensive than most other insulations on the market. Now if you are not building a double wall or a wall using a hat channel system then by all means use Rockwool. It will help some with sound reduction. However, if you are building a true soundproof wall system then the Rockwool is a waste of money. Let's look at the costs comparison. 

Rockwool Safe N Sound - $0.95 per sq/ft (Home Depot in 2023)

Owens Corning R13 Kraft Insulation - $0.55 per sq/ft (Home Depot in 2023)

You save $0.40 per square foot which can add up. If you are building a 300 square foot studio with 10 foot ceilings then you would spend: 

Rockwool Safe N Sound = $1,045

Owens Corning R13 = $605

That is a savings of $440! 

Most people want to save money where they can during a big construction project. This is a place where that money could go towards another purpose. I always recommend spending more money on mass when you can. So putting that savings towards another layer of drywall would be far better spent than on Safe N Sound. 

Don't get me wrong, Rockwool is great for acoustic panels it just really doesn't help in a soundproof wall system. If you are building a wall in your home and you are not soundproofing that wall then use Safe N Sound. However, if you are building a recording studio or any serious soundproof room I do not recommend wasting money on Safe N Sound insulation. 

Free Acoustic Treatment Guide - www.soundproofyourstudio.com/acoustic

If you are reading this, you may be facing some room ratio madness yourself. If you are trying to find the perfect room ratio, reading obsessively about room modes and genuinely feel like you have gone down a rabbit hole then you are in the right place. In this article I will ease your stress around room modes, and room ratios and hopefully send you back out in the world with a plan for your home recording studio. 

Room ratios were created to give acoustic designers (aka you) the ability to design rooms with relatively small volumes that will still sound "good." I write good in quotes because we can never achieve a perfect room. Even the best room ratios will have flaws that need to be addressed. 

This said you may have jumped on a few room ratio calculators on the internet and found that with your ceiling height the room ratio given leads to a very small room. This is a common problem with using room ratios in basement, bedroom or garage home studio designs. We are always held back by our ceiling height because the ratio is based off of ceiling height to width to length and a low ceiling height means smaller length and widths to meet the ratio numbers. Meaning, if we can't raise up our ceiling height we can't get a big enough room to do our work in. 

Totally maddening...I know! So what is the solution. Well let me tell you, but first let's learn what makes a room "good" to begin with. 

There has been a lot of research on what makes a room sound pleasing or good to the human ear. This is a subjective term and has been argued over the years by some of the world's top acousticians. 

One thing that makes a room sound good is having what is known as an even distribution of modes. (Now I am not going to get into what a room mode is in this article, but if you don't know, take a break and google it real quick.)

Okay great, so an even distribution of modes means that modes are spaced evenly through each 1/3 octave frequency band. The human ear perceives sound based on a logarithmic scale and acousticians have plotted frequencies based on this scale. The key here is to know how to read it, not try to fully comprehend the science.

Next, another thing that makes a room sound "good" is to never have modes fall on top of each other. This means two different types of modes (axial, tangential, oblique) line up at exactly the same frequency thus causing that frequency to ring out more in your room making your room sound "bad." 

To do this I am going to show you a really good room ratio and a very very bad room ratio. This will help you see what an even distribution of modes looks like and what the lining up or coincidence of modes looks like. 

 Arguably, one of the best room ratios is Sepmeyer's first ratio of 1: 1.14 : 1.39. Now, we will see in a moment how best can be misleading, but stick with me here. The image below is from the AMROC room mode calculator. It shows Sepmeyer's first ratio with a ceiling height of 15 feet. 

Now we don't really need to look at anything above 125 Hz. The reason is that we can easily treat those frequencies with velocity based acoustic panels. What is harder to treat are room modes below 125 Hz.  Now what we notice first is that in the lower frequencies we have a relatively even spacing of room modes. That is good! In a second you will see what big gaps will look like. We also want to look at the Bonello chart. It shows a smooth increase in modes per 1/3 octave. That is also considered "good." If that number goes up then drops down, then your room will not sound as good. 

I know I hate seeing that statement too, but in room acoustics the volume of our room also matters. You could use that awesome Sepmeyer ratio, but if you have an 8 foot ceiling it will not sound as good. Let me show you why. 

Below is another screen shot from the same Sepmeyer ratio we used on the 15 foot tall room. However, this chart shows the room modes for an 8 foot tall room. 

At first glance they look the same, right? But wait! The relative distribution, meaning the spacing between the modes is the same, but where the modes fall on the musical scale has changed. In a smaller room those same modes have been shifted up in the low end. This means we have more problem modes in our audible bass frequencies than we did with the larger room. 

Notice how the first mode in our 15 foot room started well below 30Hz - barely in the audible spectrum of hearing, while that same mode falls at 50Hz in our 8 foot room, right in the middle of your kick drums thump! 

This is why bigger rooms meaning taller ceilings are better for music spaces. Because the problem modes get shifted lower and lower. This means treating our room becomes easier and less expensive because we have less low modal issues we need to smooth out. 

The worst room you could possibly build is a cube. If the dimensions are 1:1:1 then your room will sound bad. Your room will also sound bad if you use even multiples like 1:2:3. So for the sake of learning how to read the AMROC calculator let's now look at that dreadful cube room. 

Gross! I mean that is just repulsive looking. Okay I kid, but yes this room will definitely sound bad and will be difficult to acoustically treat. Why? Well, first we have large gaps between those modes in the low end. Notice how our 8 foot tall room above has more lines in the low frequencies. Well, that is a good thing and we want them spaced evenly. 

Next, the Bonello criterion shows that we have a drop in modes from 3 to 1 and then a huge jump to 12. Considering ideally we want those numbers slowly increasing or at least staying the same, this is also a problem. 

Lastly, we didn't talk about this yet, but notice how there are a lot of bunched up lines that are red, blue and purple in the Sepmeyer rooms? Notice also how they start bunching together at lower frequencies than the cube? 

The bunching of lines is what we want. That actually makes the room sound more smooth and even. The big gaps make the room sound wonky because certain notes are louder than others or they may disappear completely depending where you stand in the room. Ideally, our low end would have a ton of lines too, but we just can't get that due to physics. Bummer I know!  

So, a good room will have those bunched lines start clumping together as low as possible. This is known as the Schroeder Frequency. That is just a fancy term that states when your sound waves stops behaving like waves and act more like rays. We want the sound in your room to behave like a ray at as low a frequency as possible because it is easier to treat with velocity acoustic panels. So, all you need to know is that the lower the Schroeder Frequency the better. Simple!

Okay, sorry if I lost you there, but all you need to know is: bunching together good. Bunching together at lower frequencies good. The more bunching the better and bunching evenly is the best! Yay!

Lastly, in our cube room several of the modes in the low end happen at the same frequency. Remember these are bad and will mean certain notes in your room will ring out more leading to an uneven listening and recording environment. 

Ahhhh but, Wilson, I am still reading and you have not offered me a solution yet. I know, but I need to teach you how to read the calculator so you can move beyond the room ratios. More on that in a second. 

You may have noticed a little box labeled Bolt Area in the bottom right of the diagrams I have shown you. You may also have noticed that none of the rooms I have shown you fall in the bolt area. 

First, The Bolt Area was a diagram created by Bolt (acoustician dude) who wanted to make it easy to find good room ratios. Before computers you could look at his graph and pick some room ratios that fit your design and would just hope that the room modes were evenly spaced. 

The problem is that people have found many room ratios in the bolt area that really are not so great. This lead to other graphs being created. Here is a super handy tool you can use to dive deeper on room ratio graphs. 

This link - https://www.acoustic.ua/forms/rr.en.html

The link above will show you where your room ratio falls according to the Bolt Area, The European Broadcasting Recommendations and the IEC Recommendations for room ratios. On top of that the acoustician Trevor Cox did an analysis of rooms and found out some more cool stuff. 

He says that if your room falls in the gray or black area of the graph then you will have a nice room. If it falls in the white area then things will go south for you. Dang! Notice that the calculator has a drop down menu for "room cubing." Make sure to set that number to your rooms volume. So for our situation it should be at 100 cubic meters not 50. 

Let's take a look at our 15 foot Sepmeyer room on this calculator. 

Now it's hard to see, but I think we fall on a grey area. However, we really don't fall within any of the other recommended areas. You can see how this is all maddening. Remember, these calculators are meant as tools and a guide. The best room for you will be one that has as smooth a mode spacing as possible, has a slowly rising mode count per 1/3 octave band, and most importantly is big enough for you to do the work you need to do in there. 

I have just taught you how to read these calculators and diagrams. What I propose you do is put in your ideal dimensions and adjust those dimensions slightly to try and get your room to meet the criteria I mentioned. Stay away from 1:1:1 and 1:2:3 ratios. 

Another little trick if you have bad dimensions, say 8x8x8, is to increase and decrease two dimensions by 5%. So you could decrease the width by 5% and increase the length by 5% and your room would be much better. (Myth: Modes and Room Ratios: “I Have Too Many Modes! I Need a Better Ratio to Get Rid of Them” - Soundman2020 - Studio Design Forum)

If you can raise your ceiling height do it. If you are building from scratch choose the first Sepmeyer ratio and move on. Or you could look at Louden, but don't get too hung up on it. If you use a room ratio you are light years ahead of most home studios. You could also choose to plot a room on the dark area of the Cox calculator. Then you could check it on AMROC and see how the mode separation looks in the low end. Then you could make sure it meets Bonello's Criterion. The goal is to do the best you can with what you have and not lose sleep over it. 

There is no perfect room. I repeat, there is no perfect room. Your design must use these tools and still meet your needs. My advice is to pick a room size as best as you can and move on. Don't waste weeks and weeks calculating room sizes. In the end you will still need acoustic treatment no matter what. 

One last thing...don't build a cube. 

Works Cited

Room Sizes Compliance With International Standards and Recommendations. www.acoustic.ua/forms/rr.en.html.

“Amroc - THE Room Mode Calculator.” Mag. Andreas Melcher, amcoustics.com/tools/amroc.

Myth: Modes and Room Ratios: “I Have Too Many Modes! I Need a Better Ratio to Get Rid of Them” - Soundman2020 - Studio Design Forum. digistar.cl/Forum/viewtopic.php?t=557.

Everest, Frederick A., and Ken C. Pohlmann. “Modal Resonances.” Master Handbook of Acoustics, McGraw-Hill, New York, 2015.

Free Acoustic Treatment Guide - https://www.soundproofyourstudio.com/acoustic

When acoustically treating a room we have two major forms of acoustic treatment. The first method is using velocity absorbers and the second method is using pressure absorbers. To fully treat and balance a room we need to use both tools for two different purposes. In this article I will go over what each absorber is and how to use them. 

Velocity absorbers are what you most likely think of when you think of acoustic panels. They use insulation and an air gap to absorb sound waves and reduce reflections back in your room. Velocity absorbers also include foam panels which absorb sound through transfer to heat much like fiberglass insulation. 

Velocity absorbers are great and affordable for treating your room, however they do have limitations. They are great at absorbing higher frequencies above 125Hz, but do very little at absorbing frequencies below 125Hz. 

The key attribute all velocity absorbers have is a porous composition. The air space within the material is what turns sound energy into heat because the fibers vibrate and create frictional resistance, which is then transferred to heat energy (Everest, Pohlmann 191). 

According to The Master Handbook of Acoustics, "there is little difference above 500Hz as thickness is increased (Everest, Pohlmann 195). However, there is "considerable improvement below 500 Hz as thickness is increased" (Everest, Pohlmann 195). A four inch thick fiberglass panel of 3-lb/ft3 density has nearly perfect absorption over the 125-4k Hz region (Everest, Pohlmann 195).

Adding a three inch airspace behind panels will increase its absorption. It is a best practice to leave an air gap between the fiberglass and your wall. In general the farther the panel is placed from the wall the lower frequencies it should absorb. As a general rule with velocity based traps a panel placed a 1/4 wavelength from the wall is where absorption is greatest (Everest, Pohlmann 195). 

For example, if we estimate the speed of sound to be 1,125 ft/second in our room then a 100 hz wavelength = 11.25ft (1,125 ft/sec / 100 Hz). 

A quarter wavelength of 100 Hz is then 11.25/4= 2.8125 feet. This would mean your velocity panel would need to have a nearly three foot air gap behind it to maximally absorb 100 Hz. 

Now most people cannot give up 3 feet on all their walls and ceilings to absorb down to 100 Hz. This is where pressure traps come in. 

However, before I dive into pressure traps. It is important to realize that velocity traps, although not efficient at absorbing sound below 100 Hz still absorb some in that area. This is very important because our goal as acoustic designers is to get the room as good as possible with velocity based absorbers as we can and then move to pressure based traps to sniper out some of the low frequency problems in our room. 

Pressure based absorbers also known as resonant or reactive absorbers use a different method than velocity absorbers to absorb sound. There are two main types of pressure absorbers: Panel or Diaphragmatic absorbers and Helmholtz Resonators. These two types of tools can pinpoint problem frequencies in your room below 125 Hz where our 4" thick velocity traps are not as efficient. 

Notice that I said pin point. The down side to pressure traps is that they have a narrow frequency band that they absorb. They can be tuned to attenuate specific problem frequencies in your room. 

For this reason, I always recommend that designers begin by treating their room with plenty of porous absorbers before going down the path of using pressure traps. 

Pressure traps are great at reducing room mode issues. Every room will have low frequency resonances that can muddy how we hear the bass in our room from what is actually coming out of our monitor speakers. In order to fix these low bass mud issues we can target a specific room mode issue with a tuned trap. 

Panel traps are great at absorbing lower frequencies. They are essentially a wooden sealed box with a layer of fiberglass inside. The mass of the panel and the air spring created will absorb sound as the material is flexed and vibrates. There is additional absorption through damping by the insulation (Everest, Pohlmann 195). 

Another form of panel absorption are Polycylindrical absorbers, which work the same as a flat panel absorber, but have the added benefit of creating a diffuse sound field because of their semi cylindrical bulkheads. 

Helmholtz resonators are cylindrical tubes much like a bottle. They absorb sound by using the air in the cavity as a spring that creates a resonant system. Just like blowing across the top of a bottle produces a resonant tone, helmholtz resonators also have a resonant tone and absorption is maximal at that resonant frequency. 

Helmholtz resonators can be tuned to target specific problem frequencies in your room. I will say, in my research many people have warned that Helmholtz resonators are not easy to make and small errors in construction can render them useless. 

Acoustically treating a room is like an onion. You start on the outside and get good results and gradually work your way towards the center getting more precise and more complicated as you go. For most DIY studios using velocity based traps will go a tremendously long way towards fixing your room issues. I also love room eq software like Sonarworks Sound ID to correct your speakers to fix issues in the low end. This can help mitigate problems when you are mixing or mastering. 

However, once you get your room dialed in as best as you can with velocity porous absorbers, next you will need pressure traps to reach those lower problematic room modes. To find your room modes you will need to test your room using a measurement mic and software like Room EQ Wizard. This will tell you what is wrong at your listening position and what room modes are ringing out at your listening position. 

From there you can build pressure traps to target those specific problem frequencies. 

Works Cited

Everest, Frederick A., and Ken C. Pohlmann. “Absorption.” Master Handbook of Acoustics, McGraw-Hill, New York, 2015.

FREE Soundproofing Workshop: https://www.soundproofyourstudio.com/workshop

A member of our soundproofing community recently asked me about a product called HushFrame Rafts. I had never heard of them before so I did some research. In this article I am going over the benefit of using HushFrame Rafts, the cost comparison to other similar products and what they are. 

I am usually very skeptical about soundproofing products. These Hushframe rafts are interesting though. They are a wood isolator used to decouple drywall from walls and ceilings using hat channels or wood channels. 

One of the biggest benefits to Hushfram rafts is that you can use wood as a furring channel not just metal, and you can save some space when using the Hushframe Rafts. 

According to their website, HushFrame rafts use Vi-Bridge Technology to reduce noise transfer through the clip into your drywall. Now that sounds like some fancy naming for a patented technology. That is okay as long as it works. 

According to their website they can achieve 80% noise reduction, and an STC of 66. However, we don't know what 80% noise reduction really means, especially for bass frequencies and we don't know how the wall was built to achieve an STC of 66. 

All this said, I would trust that these clips do in fact decouple drywall when installed correctly. So next let's look at another comparable product. 

Now the biggest difference in HushFrame Clips versus the IB-1 Iso Clips I used in my studio are price and the total depth of the clip. First, let's take a look at price. 

HushFrame Rafts are available at the ISOSTORE online for $4.95/clip. 

The iso-clips I recommend I found for $1.79 at Buildcorpdirect.com. 

The first important factor is to look at price. The A237 Resilimount Clip is $3.16 cheaper than the HushFrame Rafts. This could add up depending on how many clips you need. Most studios will need dozens of clips, so cost could be a factor. 

Second we want to look at the amount of space each clip adds to the wall assembly. The Hushframe Raft as you can see below uses up to 1" of space if using 3/4" wood furring or 1 1/8" if using 7/8" furring channel. 

Source Image: HushFrame Website

Now if you are using the IB-1 or A237 Clip (they are the same with different names) then you will have a 7/8" furring channel sitting in the clip with a few 16ths of an inch below the furring channel. I am not 100% certain on that exact height but it should be around 1" to maybe 1" 1/8". Either way, I believe the space saved using the HushFrame Raft is pretty minimal. 

Below is a diagram of the A237 Clip:

Now let's look at a diagram from the Soundproofing Company Website that shows different STC ratings using the IB-1 iso clips and 7/8" furring channel. 

You can see that if you use Green Glue between the layers and two layers of drywall with Green Glue on the backside you get an STC of 71. With one layer of drywall on one side and the hat channel system on the other side with Green Glue you get an STC of 67. If you use two layers of drywall without Green Glue you get an STC of 58. Those are all better than the HushFrame Rafts accept the STC of 58. However, remember we really don't know what wall system they were referring to. If you added another layer of drywall to the outside of the wall it would increase the STC regardless of your iso clip.  

Would I use the HushFrame Rafts in a soundproof studio build? Probably not because I can get the same STC rating using a cheaper clip and the space saved is pretty negligible. 

The only time I might recommend the use of Hushframe Rafts is to create a decoupled vent through your wall. I could see how using the rafts to build a custom ventilation system could be useful, but other than that I would stick with the cheaper clips and put your money on more drywall and Green Glue. 

FREE Soundproofing Workshop: https://www.soundproofyourstudio.com/workshop

When designing a soundproof room, acoustic designers will use Noise Criterion Curves or NC curves for short to ensure the room meets proper sound isolation guidelines. In this article I will go over what NC curves are and how to use them as a guide for your own studio build. 

Noise Criteria levels are benchmarks we can use to get our soundproof rooms to an industry standard. Here are some guidelines for NC Levels for various applications: 

NC 15-20: Broadcasting Studios, Concert Halls, Recording Studios and Music Rooms

NC 30: Residences, Theaters, Libraries, Executive Offices

NC 35: Private Offices, Schools, Hotel Rooms, Churches, Hospitals

NC 40: Labs, Dining Rooms, General Office Use

NC 45: Retail Stores, Lobby Areas, Reception Areas

NC 50+: Computer Rooms, Print Machine Rooms

Studio designer and soundproofing expert, Rod Gervais states that his goal when designing professional recording studios is to shoot for NC 20 or below and preferably NC 15 if possible. (Gervais 158)

Each of these NC levels represents acceptable sound pressure levels at eight octave band center frequencies. Below is a diagram from Home Recording Studio: Build It Like The Pros by Rod Gervais. 

Notice for a studio to fall in the NC15 range you must get 47 dB at 63Hz, 36dB or below at 125Hz and so on. Now that you understand the concepts behind NC levels you might be wondering how to calculate these levels in your own home studio. 

NC levels are not easy to calculate without the right tools and experience. For this reason I recommend using the chart above as a guide and using your smart phone to record levels. Although, this is not a great method for professionals for the average DIY studio build getting some general ideas of how much isolation you need is helpful. 

I recommend using the DecibelX app. You can download it for free and can pay for an upgrade if you want. This app allows you to measure the average dB level in your room and you can see the dB range over the frequency spectrum. This will help you see where you may have potential problems in your soundproofing design. 

If you want a professional level test done then you will either need to hire someone with the right experience running NC level tests or rent the right gear and read the guidelines. 

The American National Standards Institute (ANSI) provides guidelines for getting accurate measurements. You can look those up at ANSI S1.13-1971 (R 1986) American National Standard Methods for the Measurement of Sound Pressure Levels (Everest Pohlmann 313).

If you do your own measurements you will need to calibrate your SPL meter. You will also need a meter that can measure octave band frequencies and it should be mounted on a tripod for accurate results. 

As you can see, there is a reason professionals do this work. It must meet stringent standards to qualify as credible data. 

The choice is up to you if you want to try measuring NC level at all. I find the knowledge useful in understanding benchmarks for professional studio design, but probably overkill for the average DIY home studio build. 

 Works Cited

Everest, Frederick A., and Ken C. Pohlmann. “Modal Resonances.” Master Handbook of Acoustics, McGraw-Hill, New York, 2015.

Gervais, Rod. Home Recording Studio: Build It Like The Pros. 2nd Edition, Course Technology Cengage Learning, 2011. 

FREE Soundproofing Workshop: https://www.soundproofyourstudio.com/workshop 

This week things are a little different. This video is actually the visual part of a blog article I wrote for the Sonicscoop blog. If you have not heard of Sonicscoop they are a great resources for all things home recording related.

You can read the full blog article at - https://sonicscoop.com/soundproofing-your-home-studio-101/ 

0:00 - Intro

1:44 - Soundproofing vs Acoustic Treatment

3:12 - The Three Pillars Of Soundproofing

5:36 - The Best Soundproof Floor

6:37 - The Best Soundproof Wall

8:14 - The Best Soundproof Ceiling

9:00 - The Importance of Fresh Air

10:07 - Soundproof Doors and Windows

12:46 - Conclusion

FREE Acoustic Treatment Guide: https://www.soundproofyourstudio.com/acoustic

You may have visited some professional recording studios and noticed that the rooms had high ceilings, especially the tracking room. Now in your home studio do you need a high ceiling? In this article I will talk about why higher ceilings are beneficial and some of the room acoustic theory behind recording studio room design. 

A very basic, but important reason large pro studios have high ceilings in the tracking room is to give the wave forms enough space to develop before hitting a surface and reflecting back to the microphones and your ears. This is especially true when recording drums or large ensembles like an orchestra. 

In most home studios an 8 foot ceiling barely gives you enough height to place the overhead mics. You will mostly pick up the cymbals in a lower studio and the reflections from the ceiling will create a "harsh" tone. This is a very practical reason for having larger ceilings, but what about the physics of room acoustics?  How do room acoustics improve with higher ceilings?

To really grasp why higher ceilings are beneficial in a room, we must first understand some basic room acoustic physics. All rooms create reflections where sound waves bounce off of. When sound emanates from a source, say a speaker, the air in the room is excited by the sound waves. The sound travels in all directions from the speaker and bounces of the walls, ceiling and floor. When the sound bounces off the surfaces it then returns back into the room. The reflected waves then encounter new sound waves coming from the speaker and they interact with each other. The sound waves either create a boost because of constructive interference or they create a null known as destructive interference. 

These peaks and nulls in the sound waves create acoustic distortions. Now, there is a slight difference in how higher frequency sounds behave versus lower frequency sounds. Sound waves above 250Hz perform more like a "ray." Meaning they travel in a direct line and don't have as much energy as sound waves below 250Hz. 

Sound waves below 250Hz and especially below 100Hz have much more energy and have much longer wavelengths. These sound waves create what we call room modes. These room modes or are areas of high or low pressure due to those sound waves running into themselves after bouncing off your rooms surfaces. 

Okay, that was a bit complicated, but it is very important to understanding why high ceilings are important. The reason is that we ultimately want larger rooms to allow for enough space for those low frequency waves to fully form or at least form as much as they can before hitting a surface. Depending on the distance the waves travel from a source (speaker) and a surface (ceiling) the room modes will change. 

This brings us to the next point about ceiling height. The ceiling is only one part of the room. We must also consider the length and width of our room when designing a recording studio. Over the years some acousticians have come up with room ratios that create a pleasing acoustic environment for sound reproduction. 

These room ratios should be considered a starting point and are by no means the end all be all of acoustic design. You may be wondering as I did why we don't know the way to design the perfect room for a recording studio. After all, if we can measure room modes and use room ratios to reduce them why not build the perfect mathematically correct studio? 

The answer is that, acoustics is as much an art as it is a science. Just because one room sounds good to one person does not mean it will sound good to another. In fact, the way we perceive sound is uniquely human. We do not hear everything the way the math works out in physics. We hear how our ears and brain perceive sound in a room. This makes the job of designing your studio that much less precise, but also gives you the freedom to design a room that is pleasing and does the job you need it to. 

All this said, we can use room ratios to get us in the ballpark with a room that will have less acoustic problems and thus cost less to acoustically treat in the long run. 

Some common room ratios are from the acousticians, Sepmeyer, Louden, Volkman and Boner. Below is a diagram of some of their room ratios. 

Now you can use these ratios, but you are not guaranteed great results if your room is still small. The reason is that if your rooms dimensions are comparable to the wavelengths of audible sound then may have problems with "excessive separation between modes." (Everest,Pohlmann 261) The large separation between modes leads to unpleasant acoustic distortion in your room. 

To get uniform spacing between room modes and avoid coincidences (where modes pile up on top of eachother) you need more room volume. This means larger rooms are generally thought of as sounding better and are preferred for tracking rooms and control rooms. However, in control rooms the reverb time must be lower and all reflections must be treated to create a flat listening response. 

It is very important to remember that "there is no ideal ratio of dimensions" for a room. (Everest,Pohlmann 256). As studio designers we can only create a good starting point and then measure and analyze the room once it is built. 

For most of you reading this, I would assume you are working with rooms you already have or may be able to build a studio in your backyard. Either way it is important to remember that the larger the volume the better your room will sound and if you use room ratios you will have a better starting point. 

In a basement studio this could mean building a wall in the existing basement to create an ideal room ratio. In a studio build in a backyard it could mean building a larger studio to help with even distribution of room modes and avoiding coincidences. 

To answer our original question. The ideal ceiling height is probably the tallest ceiling you can afford while making sure it fits within a good room ratio for the least acoustic distortions caused by room modes. In the end don't lose sleep over this, but know that understanding room modes is an important aspect of getting your room to sound as good as it can from the start. 

Works Cites:

Everest, Frederick A., and Ken C. Pohlmann. “Modal Resonances.” Master Handbook of Acoustics, McGraw-Hill, New York, 2015.

FREE Soundproofing Workshop: https://www.soundproofyourstudio.com/workshop

In this podcast I am using my Decibel X app on my phone to record the decibel levels at various spots in my studio while the mini split is on, off and in silent mode. 

The goal of this video is to give you some solid numbers and video audio to base off your decision to purchase a Mr. Cool Mini Split. 

In my experience the mini split is plenty quiete for recording vocals, acoustic guitar and other softer instruments. 

I also give you a bonus set of videos showing how loud my ventilation system is. 

In the end I still recommend the Mr. Cool Mini Split in most studio builds because it works and is affordable. Yes, a ducted mini split would be quieter, but would also cost several thousand dollars more.