Need Advice for Treating Acoustics in My New Home Studio

Hello all, I’ve been doing a lot of lurking here lately and have finally decided to throw my hat into the ring and ask for some help. I need some advice in tuning my studio at a house we will soon move into located in Denton, TX. The room is located on a far side of the house on a four acre property. I play drums and keyboards. I don’t think sound penetration is going to be much if any issue here (for the first time ever!). The main thing I want to do is tune this room to be a first rate acoustical environment for: listening to music (both stereo, and 5.1) composing, arranging and mixing music practicing and teaching percussion using room as a home theater Please excuse my crude drawing (although it is to scale) The room is 22 feet on the long side and 15 feet wide with a short hall space which is 7 feet long by 5 feet wide. Ceiling is 10 feet high. Everything is unfortunately parallel. Five doors!!! Wow! Here’s a breakdown: Bottom left door goes to garage Bottom middle goes into butler’s pantry and then kitchen Bottom right goes into storage room Hallway side door goes into a restroom Hallway back door goes into backyard The room was initially built as a second living area. It currently has a tile floor and sheet rock walls and ceiling, with five doors and a large window. In its current state it sounds like a small gym. My job is to tune the room so that it will absorb sound, have as flat a frequency response as possible, and be suitable for my musical pursuits. I plan on carpeting the floor because: I like the way it looks, feels and functions as an acoustical absorber of sound. After reading lots of posts here, I have begrudgingly decided to set up my mixing desk so that the speakers fire into the long side of the room (even though I am blocking a window view of a beautiful four acre meadow!). I plan on covering much of the walls with 24 x 48 panels of Owens-Corning fiberglass insulation. I will place panels where the wall meets the ceiling, all the way around the room (even in the small hallway on the upper right). I’m also going to mount 24 x 72 bass trap panels in the corners located at the top left of the room and far right corner of the hallway. I plan on mounting the “Ethan Winer” type panels on all three back doors with similar panels in the wall corners adjacent to the door panels. I’ll also use “Ethan Winer” type 32 inch triangle traps in the tops of all corners and in the bottom of the upper left corner and in the bottom of the far right hallway corner. I plan on putting clips on all wall and door panels so that they will be three inches from the wall. Questions: Should I use OC 703 or 705 fiberglass (or a mixture)? Should I get the FRK version with a membrane on the back? It looks like the first reflection point on the right wall will be somewhere in the middle of the hallway passage. How should I deal with this? (I don’t really want to move my mixing desk back because it will block access to the hallway.) What sound acoustical issues am I going to face with that hallway on my right side? ... and will it make a difference that the first reflection point is treated differently on the right and left wall? I am thinking of getting some curtains to put behind my monitors to take up behind-monitor wall reflections. Opinions??? For the two long walls, in addition to the sideways panels mounted where the wall meets the ceiling, I am going to mount several 24 x 48 panels about six inches apart, up and down along the wall. Should I use OC FRK fiberglass (with the membrane), alternating with the membrane on the outside and inside for a randomness of reflection and absorption? Is any diffusion recommended for the back wall? I’m at a disadvantage with the door in the center of the room. I really don’t have a plan in place for ceiling absorption yet. I know that I need to mount several panels, beginning with first reflection points from my monitors but then what? I am not new to building home studios. When we recently moved, I (reluctantly) gave up a great home built studio: http://www.mikemyersmusic.com/studio.html This studio was built 21 years ago and I used it every single day. There are many who would not agree with my wall treatment, however, that room sounded great. In my new studio, I want to take it to a higher level and really do it first rate in terms of sound and a flat frequency response. I appreciate any and all advice by the experts who hang out here! Mike Myers mikemyersmusic.com

Hi Mike, welcome to the forum! Several comments, in no particular order of priority, since they are all rather important:

I don’t think sound penetration is going to be much if any issue

Are you certain? It never rains where you are? No cars ever drive by? No planes fly over? No thunder? The wind never blows? No other people in the house that might talk, turn on the radio / TV / vacuum cleaner / washer dryer / talk to each other....? No water runs in pipes? No air conditioner / furnace? No toilet flushes? No phones to ring? No neighbors with barking dogs / lawnmowers / cars / motorbikes? No helicopters ever fly over? etc. The point is, even though your sound going out might not be an issue for anyone, their sound coming in might indeed be a big issue, if it wrecks that "one perfect take" that you just cannot manage to reproduce... So you might want to re-think that isolation issue.

Please excuse my crude drawing (although it is to scale)

An accurate scale version in SketchUp would be more useful. It's hard to figure things out from a simple paper sketch.

The room is 22 feet on the long side and 15 feet wide with a short hall space which is 7 feet long by 5 feet wide. Ceiling is 10 feet high.

The good news: Those dimensions are spot on for Louden's 4th best ratio! That's a good ratio! (1 : 1.5 : 2.2) The bad news: that "short hall space" is a major, major issue.

Everything is unfortunately parallel.

Not a problem. That can be dealt with.

I plan on carpeting the floor because: I like the way it looks, feels and functions as an acoustical absorber of sound.

Bad idea. In general carpeting a studio floor is not a good idea, for many reasons. One of the biggies is that typical home carpeting is actually NOT a good acoustic absorber: it is selective! It absorbs some frequencies better than others, and in fact absorbs the ones that you DON'T want to absorb, while not absorbing the ones that you DO want to absorb. Much better would be to simply leave the tile floor in place. That's a pretty good floor, acoustically speaking. Or if you don't like tile, then replace it with laminate flooring. But not carpet. (Unless you know the detailed acoustic properties of the exact carpet that you plan to use: most carpet manufacturers never measure the acoustic response of their carpets, so you will be entirely on your own as to how that will affect the acoustics of your studio).

I plan on covering much of the walls with 24 x 48 panels of Owens-Corning fiberglass insulation.

Covering too much of the walls lie that might be a bad idea. It could easily end up making the room dead or dull sounding, which is not good.

I will place panels where the wall meets the ceiling, all the way around the room

Good idea!

It looks like the first reflection point on the right wall will be somewhere in the middle of the hallway passage. How should I deal with this? (I don’t really want to move my mixing desk back because it will block access to the hallway.)

That hallway is your first, biggest, and most deadly acoustic issue in the entire room. See below:

What sound acoustical issues am I going to face with that hallway on my right side?

Very large ones!

... and will it make a difference that the first reflection point is treated differently on the right and left wall?

Yes, a big difference! Let me explain: one of the basic requirements for a successful control room, is symmetry. If you don't have good symmetry in the front half of your room, then you don't even HAVE a room! You absolutely must have a symmetrical front end, and especially since you say that your goal is to make "this room to be a first rate acoustical environment for: listening to music (both stereo, and 5.1), composing, arranging and mixing music...". without symmetry, your chances of doing that are around zero. You need to have a clear, open, accurate "sound stage" in front of you, meaning that you can clearly hear the exact position and tone of each instrument, in its correct location between the speakers. Without room symmetry, that is impossible. And that hallway is a huge, glaring, major kludge on room symmetry. It is basically a resonant cavity on one side of the room, and it will totally destroy any chance of getting a decent sound stage. Second, you need your to hear accurate, flat, and exactly equal response from both speakers. Your right speaker is hanging on the edge of a huge tuned cavity, that will grossly mess up the lows and low mids. It will do not give you an accurate response curve that is the same on both sides. So your mixes will just not "translate", meaning what you mix in that room will sound totally different when played anywhere else. In other words, that hallway simply isn't going to work: You have to do something about it.

Is any diffusion recommended for the back wall?

Not really. The room isn't big enough to benefit much from diffusion. And your back wall would probably be better off with deep absorption on it.

For the two long walls, in addition to the sideways panels mounted where the wall meets the ceiling, I am going to mount several 24 x 48 panels about six inches apart, up and down along the wall.

I'd consider slot walls, if I were you. They look great, and also do a great job on treating the room, acoustically. So the big issue that you need to re-think is what to do about that hallway, or how to re-arrange the room otherwise, so that you get really good symmetry, at least for the front half of the room. I'd work on that, then once you have that "500 pound gorilla" problem solved, then start planning the rest of the room. I'd also use SketchUp to do that. - Stuart -

Stuart, Thanks for the reply!

Please excuse my crude drawing (although it is to scale)

An accurate scale version in SketchUp would be more useful. It's hard to figure things out from a simple paper sketch.

I downloaded SketchUp today and am trying to learn it

I plan on carpeting the floor because: I like the way it looks, feels and functions as an acoustical absorber of sound. Bad idea. In general carpeting a studio floor is not a good idea, for many reasons.

I figured that this would open up a can of worms around here. Seems to me that there's not that much difference between carpeting the floor or having a ceiling that is totally muffled with sound insulation. I may be wrong here. Also, I am one of those people who like to record very dry and add in my own ambience.

In other words, that hallway simply isn't going to work: You have to do something about it.

Got any advice???

... and will it make a difference that the first reflection point is treated differently on the right and left wall?

Yes, a big difference! How about if I put a curtain over the hallway and also use a curtain on the left wall for my first reflection absorption?

For the two long walls, in addition to the sideways panels mounted where the wall meets the ceiling, I am going to mount several 24 x 48 panels about six inches apart, up and down along the wall.

I'd consider slot walls, if I were you. They look great, and also do a great job on treating the room, acoustically.

I'm not sure what you mean by slot walls? Thanks again for your advice, Mike mikemyersmusic.com

I downloaded SketchUp today and am trying to learn it

Great! It takes a little while to get your head around some of their concepts, and figure out the basics, but once you do it is a really powerful, and easy-to-use tool.

Seems to me that there's not that much difference between carpeting the floor or having a ceiling that is totally muffled with sound insulation.

There's a huge difference. Carpet is "selective", meaning that it does not treat all frequencies the same. It absorbs some better, others worse, and most not at all. And it is pretty random; Most carpet manufacturers don't really care what acoustic properties their product has, since that isn't their purpose at all. So they just make the stuff, and never bother to test it. so you are totally on your own as to what any given piece of carpet will do to your room. But chances are roughly 100% that it won't do anything useful. For a start, most carpet is way too thin (just a few mm) to be effective at anything but high frequencies, and maybe high-mids. It hardly does anything at all for the low-mids, and definitely does zilch for lows. In other words, it randomly absorbs highs while not touching lows, which is the exact opposite of what you need in most studios. So it will leave your room sounding dull, "cavey", hollow, and frankly, rather ugly and unpleasant. On the other hand, the acoustic properties of the kind of treatment you'd normally put on your ceiling (EG. fiberglass or mineral wool) are very, very well understood: they have been analyzed endlessly in numerous labs all over the world, and the way they react to sound is well know, and well documented. No guessing required. Plus, they are thick! For the average studio, you'd use stuff that is at least 4 inches thick on your ceiling, maybe 6 inches in places. In other words, about 20 to 30 TIMES thicker than your average carpet. This is a whole different ball game! It is thick, so it treats low frequencies well, and low frequencies is where all your problems are going to be. And it has well-known acoustic properties, so you know in advance exactly what you are going to get. Carpet and mineral wool are totally opposite, about as different as chalk and cheese, acoustically speaking. Perhaps some people actually like the way chalk tastes, but personally I much prefer cheese! :) Next is the psycho-acoustical issue: All of your life your brain has gotten used to hearing the floor at the exact same distance, since your ears are always at the same height above it. If you put carpet on the floor and leave the ceiling reflective, your brain can't quite figure out the conflicting clues, and it just doesn't sound right. But leave your floor reflective and put in an absorptive ceiling, and your brain "gets it" right away. There are other reasons too, but those are the two big ones. It isn't really a matter of personal taste at all, but rather a matter of what has been studied extensively and shown to work or not work. Carpet is on the "not work" list, right at the top. Mineral wool and fiberglass insulation are on the "work's great" list, right at the top.

Also, I am one of those people who like to record very dry and add in my own ambience.

Then you most definitely do not want carpet on your floor! What you want is a room that is treated to sound totally natural, neither adding to nor subtracting from the sound of whatever it is that you are trying to record. Carpet will NOT give you that! It will give you dull, honky, muddy sounds. If you want a dry room, you cannot get it with carpet!

Got any advice???

OK. But first a couple of questions: Do you need access to that hallway? Can you get to those rooms through another route? Can you knock down any of the walls around that room? What is on the other side of each of the walls? I guess building new walls is not a problem,, right?

How about if I put a curtain over the hallway and also use a curtain on the left wall for my first reflection absorption?

The problem is not what you put in front of it: the problem is the hallway itself: It is a resonant cavity, that has its own acoustic characteristics that are entirely different from the rest of the room. A curtain won't fix that. At best, a really thick curtain might help with some of the highs, but it won't do anything at all for the lows. The thing here is that you have to understand some of the physics of sound waves: Low frequency sound waves, such as those produced by a drum kit, or a bass guitar, or the low notes of a keyboard, have very, very long wavelengths: many meters long. A wave basically ignores any barrier that is much smaller than itself, and is only affected by barriers that are much, much larger than it is. So a wave that is 5 meters long won't even see a curtain that is, at best, just a centimeter or so thick. It will act as if the curtain isn't even there, and go right through. Only very short waves, just a few cm long (top end of the piccolo, violin, cymbals, that kind of thing) will be affected well by the curtain, since those waves are small, compared to the size of the curtain. This is also the reason why carpet is lousy: it is too thin to affect the lows. In a small room, your major acoustic issues will ALL be in low frequencies, which are the hardest to treat because their waves are so BIG. The first rule for treating any small room is to start by putting in as many very large "bass traps" as you can possibly fit, then measure the response of the room and see what still needs to be done after that. It goes without saying that small rooms need major bass trapping, and bass trapping has to be large, and thick. Carpet and curtains are no use here. Sorry.

I'm not sure what you mean by slot walls?

Slot walls: That comes from this thread: (scroll almost to the end of the page) viewtopic.php?&p=2259&start=2259 How to build one: http://www.johnlsayers.com/HR/index1.htmEasy! And very effective. There are many, many more examples all over the forum. A slot wall is basically just a bunch of slot resonators tuned to different frequencies, and angled for lower Q and better broadband effect. It is a great idea, as it does several things at once: absorbs problematic frequencies, reflects highs back to keep the room form being too dead, and it even diffuses. What more could you want? :) (Oh yeah: also "cheap" and "easy to build"....) - Stuart -

Stuart, Thanks again for your reply. If I were paying you, I probably couldn't afford your time! I bow down to your superior knowledge of sound and acoustics. In the words of another person with the same name Mike Myers, "Not Worthy, Not Worthy!" I admit that I am much more of a creative person than a technical person. BTW, I am a percussionist and wanna-be jazz keyboardist. So, just for the sake of argument, what is wrong with a great sounding movie theater with 5.1 sound that has carpet on walls, floors, ceiling and is full of chairs made of absorptive material. The place is about as dead sounding as can be, however, it sounds great to my ears. [quoteDo you need access to that hallway? Can you get to those rooms through another route? Can you knock down any of the walls around that room? What is on the other side of each of the walls? I guess building new walls is not a problem,, right?[/quote] As you walk into the hallway, there is a restroom to the right and a door straight ahead which goes outside to the backyard. I guess I could build a wall covering the hallway and put a door which would give me access. Would that be a better idea? Let's say I go with your suggestion and ditch the carpet and keep the existing tile floor. So, would you suggest rugs or any type of absorption on the floor? Also, what should I do to the ceiling if I leave the tile floor? I am enclosing a (rather dark) photo of the room. Directly behind me is a door going into the kitchen. To the left is a door going to the garage. To the right is a door you go into and turn left and is a storage room. In the picture, the inside of the far right wall is a bathroom. Again, thanks for your expertise! ...and, is Ethan Winer in da house? Mike Myers mikemyersmusic.com

So, just for the sake of argument, what is wrong with a great sounding movie theater with 5.1 sound that has carpet on walls, floors, ceiling and is full of chairs made of absorptive material. The place is about as dead sounding as can be, however, it sounds great to my ears.

The carpet is only what you see. You do not see what is behind the carpet. There are a lot of things that could be behind the carpet. Andre

what is wrong with a great sounding movie theater with 5.1 sound that has carpet on walls, floors, ceiling and is full of chairs made of absorptive material. The place is about as dead sounding as can be, however, it sounds great to my ears.

Well, there are some major difference between a movie theater and your home studio. To start with, the movie theater is a large room, acoustically speaking, where all of the dimensions are comparable to or larger than the wavelengths of all of the sound going on in there, while your home studio is an acoustically small room, where the dimensions of the room are much, much smaller than manyof the wavelengths. These are two entirely different acoustic spaces. Large room acoustics and small room acoustics aren't really comparable. Most of the issues that affect small rooms simple aren't even on the radar for large rooms. The acoustic treatment that you need in a large room is not the same as what you need in a small room. Second, the carpet that you see on the walls of large movie theaters is usually not the treatment: it is hiding the treatment! The actual treatment is on the other side of the carpet, where you can't see it. The carpet is purely aesthetic, and it usually isn't ordinary carpet, either: it is often acoustic carpet, designed to be fairly transparent, acoustically, or at least transparent in the range that matters. One other point: the sound system used in a large modern movie theater isn't really 5.1, either... :) (At least, not in the same sense as you use that term for a home studio). Also, the acoustics you "hear" in a well designed modern cinema are not "dead", but rather neutral and "damped": Dead is something different. Cinema acoustics is supposed to be balanced, neutral, and quiet, but not really dead. If you ever get the chance to be inside an anechoic chamber for a while, then you can hear what "dead" really sounds like! Not all that pleasant, and not a nice environment for recording, practicing or listening in. Studios used to be designed to be dead a couple of decades ago, but not any more (thanks God!). Dead is not nice. Balanced acoustics is nice (not too bright, not not too dull). Flat response is nice. Neutral is nice. Short and similar RT times across the entire spectrum is nice. But dead is not nice. Here's some random stuff I found on carpets, and small and large room acoustics, and cinemas, that you might find interesting. Most of it is good, some sprinkled with not-so-good. Caveat emptor. http://www.church-acoustics.com/faq-chu ... ustics.htm http://www.lenardaudio.com/education/17_cinema_6.html http://www.tk-living.com/fabrics/images ... abrics.pdf http://www.soundcontrolroom.com/guidelines.htm (Quote from above: "Beware of thin absorbers. Carpet on walls sounds terrible and cannot be an effective acoustic treatment." How true...) http://www.avforums.com/forums/room-aco ... roach.html http://www.avsforum.com/avs-vb/showthread.php?t=1001684 And since you asked about Ethan: http://www.ethanwiner.com/acoustics.html I'm hope Ethan doesn't mind me quoting directly from his web site: "LIVE OR DEAD - WHICH IS BEST AND WHERE? If you've ever seen photos of high-end recording studios in magazines, you probably noticed that the studio room floors almost always use a reflective material like wood or linoleum. A hard floor gives a nice ambience when miking drums, guitar amps, and acoustic instruments. Likewise, auditorium stages and school band rooms always have a reflective floor surface too. As mentioned earlier, "live" in this context refers only to mid and high frequencies. I cannot emphasize enough the importance of a reflective floor for achieving a natural sound when recording acoustic instruments. If you record in your living room and your spouse refuses to let you remove the carpet, get a 4- by 8-foot sheet of 1/4-inch plywood to put over the carpet when recording." Yup!

I guess I could build a wall covering the hallway and put a door which would give me access. Would that be a better idea?

That would work, yes. It would have to be a massive studio type door (but you can built that yourself, fairly easily), but it would do the job. The problem would be that the door would end up front corner of the room, right where your speaker soffits or bass trapping should go, but there are ways of dealing with that, too. If you can't brick up that hallway entirely, then putting a decent heavy door on it will work.

Let's say I go with your suggestion and ditch the carpet and keep the existing tile floor. So, would you suggest rugs or any type of absorption on the floor?

Sure! But that would most likely only be decided in the end, once the room is finished. the general recommendation is to build the room and treat it basically, then measure the response (not hard to do) and add appropriate extra treatment, measure again and do the final tweaks, such as putting throw rugs on the floor if the room is still too bright. But if you happen to like the idea of rugs on the floor, there's no reason why you shouldn't, as long as you are not counting on them to be your major treatment for the room.

Also, what should I do to the ceiling if I leave the tile floor?

You have 10 feet up to your ceiling, which is great! More height is better, acoustically. You also have a good room ratio, and good room volume. So you'll probably only need some basic treatment up there, such as a cloud over your mix position at the first reflection points, and maybe some absorption panels elsewhere on the ceiling if you are having flutter echo or other issues, or if the room is too bright. Another approach that Ethan has tried and recommends (I think?) is to make the ceiling totally dead, meaning a thick layer of absorption across the entire ceiling. Such as 6 inches of 703, or something like that. Might be worth considering. Another quote from Ethan: "Another advantage of full absorption on a low ceiling is that it avoids the comb filtering that occurs when miking drums and other instruments from above. Placing microphones high over a drum set or string section puts the mikes very close to the ceiling. If the ceiling is reflective, sound will arrive at the mikes via two paths - the direct sound from the instrument and the same sound after being reflected off the nearby ceiling. When the difference in distance is very small, let's say one foot, the reflections cause many peaks and dips in the response, which are very audible and can sound like a flanger effect". Yup and yup. Like I mentioned on anther thread yesterday, trying to mic drums in a room with a low, hard ceiling will make them sound thin, harsh and ugly. Been there, done that. Not nice ( although some folks actually say they like the way that sounds! :shock: ) You'll still need the rest of the basic room treatment for small rooms, though: Lots of bass trapping, such as large "superchunks" in the four vertical corners (and maybe some of the other corners too), 4" of absorption on your first reflection points, good geometry for your speakers and mix position, etc.

I am enclosing a (rather dark) photo of the room.

Great! It looks like you have a good basic room there, and a plan for dealing with the hallway, so now you just need to get it all into SketchUp, do a rough standard layout for a control room, and see how it goes! Post your SketchUp model here when you have that in place, and I'm sure folks will be happy to comment on it, and offer suggestions for improving it even more. Two other points: 1. Have you decided if you need isolation yet, taking into account what I said in my first response to you? 2. Don't forget to consider HVAC and electrical in your design! You will obviously need power in your room to run your equipment, and you'll obviously also need ventilation and cooling. Those are things that should be considered up-front, not tagged on at the last minute. - Stuart -

The carpet is only what you see. You do not see what is behind the carpet. There are a lot of things that could be behind the carpet.

Damn! Andre beat me to it! Wish I'd seen that before I posted: As always, Andre can say it effectively in a dozen words, while I need an entire volume... :) - Stuart -

Soundman2020 wrote:

Damn! Andre beat me to it! Wish I'd seen that before I posted: As always, Andre can say it effectively in a dozen words, while I need an entire volume... :)

Thanks Stuart. We work together. I have become proficient at short posts because I have grown tired of writing long, accurate, posts. You do that wonderfully. May be it is that Chilean wine? :mrgreen: Andre

You do that wonderfully

:oops:

May be it is that Chilean wine?

Ahhh yes! That must be the explanation! Which gives me a great excuse to go get some more of it.... :) Especially seeing that next week is "Fiestas Patrias" here, which is our week-long equivalent of independence day. And not only that, its the bicentenary! So I have 200 years of catching up to do on my Chilean wine consumption..... :) - Stuart -

"So, just for the sake of argument, what is wrong with a great sounding movie theater with 5.1 sound that has carpet on walls, floors, ceiling and is full of chairs made of absorptive material. The place is about as dead sounding as can be, however, it sounds great to my ears." And last but not least, you are hearing the end product in these rooms, even if it is a home theater. As always, "good to my ears" is a subjective term and does not apply across the board since my hearing may miss some of the higher end frequencies and clarity/separation of the instruments/mix that someone else may take for granted or not have noticed yet.

Mike, here's some concrete data (excuse the pun!) on the acoustic properties of carpet as compared to other materials, including proper fiberglass acoustic absorption, taken from this very useful page: http://www.sae.edu/reference_material/a ... 0Chart.htm That table lists the measured acoustic absorption coefficients for various materials, in six different frequency bands. The first two bands you could call "lows", the next two "mids" and the last two "highs" (very roughly). The six frequency bands are centered on 125 Hz, 250 Hz.(lows), - 500 Hz., 1 kHz.(mids), - 2 kHz., 4 kHz. (highs) The very first line of that tables shows generic "carpet" as follows: Carpet 0.01 0.02 0.06 0.15 0.25 0.45 In other words, carpet does nothing at all to lows, practically nothing to mids, and is wildly variable across the highs, affecting sounds in the 4k range nearly twice as much as for the 2k range. It absorbs roughly 50 times as well for the highs as it does for the lows. So it will suck out a lot of the highs from your room, and only leave the lows. Result: dull, boomy, honky, hollow, cavey.... Compare that with semi-rigid fiberglass absorption: Fiberglass board (100mm(4") thick) 0.99 0.99 0.99 0.99 0.99 0.97 Now THAT is what you call effective acoustic absorption! The coefficient is practically 1 across the entire spectrum! It absorbs all frequencies equally, and does so really well. In fact, it absorbs the highest band twice as well as the carpet, but it also absorbs the exact same amount of lows, which is about one hundred times better than carpet. So if you use that stuff in your room instead of carpet, it will absorb evenly, smoothly, in a balanced, neutral manner. But since you can't walk on it, you can't put it on the floor: It has to go in the ceiling, or the walls. Hence: leave your floor reflective, and absorb properly elsewhere. Hope that helps! If you are still not convinced, compare the line for "carpet" with the line right below it, for "unpainted rough concrete": You'll see that carpet absorbs sound exactly the same as concrete does in the lows and mids, and is only marginally better in the highs.... :) In other words, carpet is about as good as concrete at treating your room, except in the high end of the spectrum! :!: :shock: - Stuart -

Stuart, Okay, I've been doing my homework and I read all of the links you posted. Seems like everyone is telling me to leave the tile floor and treat the rest of the room. Don't know if this makes any difference but I really don't do a lot of recording with microphones anymore. I have a tone of samples that I've done and I usually record drums on my V-Drums these days, using either their onboard sounds or other sample libraries that I have. So, essentially I work mostly "in the box" these days. I want a room that is good for listening to music. This would include CDs, MP3s, DVDs, internet broadcasts, etc. In addition I will be mixing my music as well as others. This room will also be used as a home theater. Currently, I have a 40 inch monitor that I use for my computer and also to watch TV and movies on. I see the monitor getting bigger in future years an maybe eventually being a screen with a projector. In addition, I will practice and teach drumset in this space. Another reason that I am doing so much research is because of my hearing loss. At 53 years old, I wear hearing aids after a life of abusing my hearing. I realize that there are a lot of acoustic subtleties I can't hear. Also, the digital hearing aids "color" everything I hear. I basically have a small P.A. system on each year and I have a small speaker in each ear which colors and compresses sound in addition to making up for my particular frequency loss in each ear. If you're interested, check out an online article and video I did this year about my journey with hearing loss: http://www.vicfirth.com/exchange/2010/0 ... instrument My goal is to have a room, where I will spend a majority of my time and be able to listen to music in a best case scenario listening environment. Even in that environment, music may sound very different to your ears than mine. Still, I want to do everything I can to give my ears the best environment to hear music. This may be slightly off topic... I recently bought a tube processor which I route all of my audio through. It came highly recommended by reviews in respected audio magazines. Honestly, my ears can’t tell a difference. But still, I want to do everything like this possible so that music sounds the best in that room. Whether my ears will be able to process the audio correctly is another matter that I have to deal with. So, can a room be designed to serve all these purposes?

Soundman2020 wrote:

Post your SketchUp model here when you have that in place, and I'm sure folks will be happy to comment on it, and offer suggestions for improving it even more.

Okay, here goes...

Soundman2020 wrote:

Have you decided if you need isolation yet, taking into account what I said in my first response to you?

Yes, I have thought about that a great deal. This is the first house that I've lived in that is semi-out in the country. The lots are all several acres big. Mine is four acres. There won't be problems with traffic, and many of the problems you listed. I'm sure that I will hear some rain and thunder. Actually I like those sounds! Also, since I work "in the box" I don't see any of these intermittent sounds being a problem. Its nice and quite at this place. If you're interested, here is how I built my last studio. I took my garage and built five rooms inside of it for soundproofing. It worked great. My next door neighbor's master bedroom was 20 feet from my studio and they NEVER heard me playing drumset, even when I was going full out, rockin' hard. http://www.mikemyersmusic.com/studiowallplans.html I'm not going to need anything this extensive at my new studio. I'm spending much more of my time and money on tuning the inside of the room. If I get in there and have issues with sound coming in, I will deal with it down the road. I really don't see that being a problem in my location. [quote="Soundman2020"][quote]Don't forget to consider HVAC and electrical in your design! You will obviously need power in your room to run your equipment, and you'll obviously also need ventilation and cooling. Those are things that should be considered upfront, not tagged on at the last minute./quote] Yes, very important!!! In my last studio, we had a separate air conditioning system installed for that room. The architect installed a bigger unit than was needed, used commercial ductwork which was lined with acoustical insulation. He made several “S” turns in order to keep sound from coming through. The cool air dropped quietly into the studio. It was extremely effective and I never heard it. I’ve been in studios where the air was really noisy and had to be turned off during recording. What a hassle, especially in July! This was never a problem in my studio. The air was always on and you couldn't hear it. Also, with all of the sound insulation on the walls, I never had to turn on the heat. Earlier this year, there was two feet of snow and ice outside but I was running the air conditioner in my studio. At the new studio, I’ve already met with an air conditioning guy. The house has two units. The unit that I’m on only controls my studio, the kitchen and a living room. He is going to insulate the attic quite a bit more. The ductwork already has acoustical lining. He is going to add several turns in the ductwork before it reaches the unit. He promises me that I won’t be able to hear the air in the room and that it should function in a similar way as my former studio did.

Please excuse the excessive posts today, but I'm on a roll! So, here is the problem spot in the studio... This short hallway. On the left wall, I have crudely tried to draw some windows. My mixing desk, which is about 9.5 feet long, will go in front of that window, with speakers on top pointing at me. So, the first reflection spot on my right is in the air on that hallway entrance. So, what if I build a wall over that space with a door that is near the window side, in the corner? It would open up into the hallway. As you go into the hallway, the door on the right is a restroom. Going straight ahead, you go out a door into the backyard. If I built over the hallway space it would give me symmetry in the room and I would be able to hang a first reflection panel on the wall, as well as deal with bass traps in the newly created corner with the door. Comments? Mike Myers mikemyersmusic.com

"If I built over the hallway space it would give me symmetry in the room " That would be the first thing I would do. A heavy wall, several layers of sheetrock on the interior side maybe even build a separate decoupled wall on the back side with as many layers of rock, fill both with insulation.

Seems like everyone is telling me to leave the tile floor and treat the rest of the room.

Yup! :) It's hard to let go of pre-conceived notions, isn't it? I know first hand: When I first started planning my studio, I ran into the same issue: I was convinced that I had to float my floor, or at least put wood or something on it, since that what I "knew" was the right thing to do... Until folks here set me straight, I did the research, and found that I was wrong about that: that the best thing for my floor is plain old concrete, or maybe with laminate flooring on it. I reckon you are at the point I got to eventually, realizing that stuff you "knew" to be "correct" actually wasn't really correct at all. There are a lot of similar myths floating around the internet, and they are really hard to kill! They refuse to just lay down and die like they should, damnit!!! :)

Don't know if this makes any difference but I really don't do a lot of recording with microphones anymore. I have a tone of samples that I've done and I usually record drums on my V-Drums these days, using either their onboard sounds or other sample libraries that I have. So, essentially I work mostly "in the box" these days.

Well, the purpose of your room is mainly critical listening, and that too requires excellent room acoustics. You still need to hear the clearest, cleanest possible sound at the mix position, without the room messing it up at all. Ideally, you want to hear ONLY the direct sound from the speakers, with no reflections arriving at your ears within a fairly long time window, and even then those reflections should be at levels that are way below the direct sound from your speakers. In other words, the room, speakers and mix position are a system that has to work together to not alter or color the sound, and to only feed you pristine untouched sound from the speakers. That's the goal. Anything that the room does to the sound means that you won't be hearing the truth, and subconsciously you will most likely try to "correct" that by adjusting eq, compression, reverb, levels, etc., to compensate for what the room is doing. This means that your mixes can end up sounding really great in your room, but they will not "translate" well. They will sound different, unbalanced, colored, tainted, etc when you listen to them elsewhere, since the "elsewhere" places will have different acoustics that do not match your room. So the goal of designing your room is to make it as neutral as possible, so you can hear what the mix REALLY sounds like, warts and all, in order to make a mix that will sound good in ANY room. In order to that, your room must be neutral, natural, balanced. It must not affect the sound in any way. That's the basic idea, and it doesn't matter where the sounds came from that you are mixing: Samples, live, or anything else: The goal is still the same: you have to hear them exactly as they are, without the room interfering.

I want a room that is good for listening to music. This would include CDs, MP3s, DVDs, internet broadcasts, etc. In addition I will be mixing my music as well as others. This room will also be used as a home theater.

Exactly. It is going to be a critical listening room, which means that the room itself has to "disappear" acoustically, as far as possible, and leave you only with the true underlying sound of your mixes, movies, samples, CDs, DVDs, or whatever.

Another reason that I am doing so much research is because of my hearing loss. At 53 years old, I wear hearing aids after a life of abusing my hearing. I realize that there are a lot of acoustic subtleties I can't hear.

I'm just a couple of years behind you, and I have some mild hearing loss too (I used to shoot, as a hobby). Mine isn't as bad as yours (I'm only about 20 dB down in the mid highs), and I don't need hearing aids yet, but I most certainly do understand where you are coming from! Which is why I'd say that in your case (and mine) having an absolutely neutral environment is even more important than for the 20 year old engineer with perfect hearing.

Also, the digital hearing aids "color" everything I hear. I basically have a small P.A. system on each year and I have a small speaker in each ear which colors and compresses sound in addition to making up for my particular frequency loss in each ear.

well, yes, it does color the sound, but from what I understand it colors it in the exact opposite way from your hearing damage, in order to compensate for the loss. It tries to make up for the ranges you cannot hear by increasing them, and compressing them. So in essence, the goal there is that your brain ends up hearing things as close as is technically possible to they way you would be hearing them anyway, if you had perfect hearing. But your aids are designed on the assumption that what the mics pick up is the “real” sound around you, so I’d say that in order for them to do their job as well as possible, the “sound around you” has to be as true, clear and uncolored as possible, just like it does for everyone else. I’m no expert on hearing loss, so maybe you should check my assumption with Dr. Price when you go for your next checkup, but it makes sense to me logically that your aids will do a much better job of correcting for you, if they have excellent sound around to start from.

If you're interested, check out an online article and video I did this year about my journey with hearing loss: http://www.vicfirth.com/exchange/2010/0 ... instrument

I read it, and Wow! Thanks! Great article. I teach a basic "sound and acoustics" seminar for musicians in churches here in Chile, and the points you make are the same ones I make. Would you mind if I mentioned you and quoted from your article in my courses (in Spanish, of course), to illustrate a real-world case? (With copyright attribution, of course). It's not easy to convince musicians to take care of their hearing, so maybe a real testimony from someone who has suffered exactly what I try to explain to them, would help to convince them. Would that be OK with you?

My goal is to have a room, where I will spend a majority of my time and be able to listen to music in a best case scenario listening environment. Even in that environment, music may sound very different to your ears than mine. Still, I want to do everything I can to give my ears the best environment to hear music.

That's what I figured! That's my goal too.

This may be slightly off topic... I recently bought a tube processor which I route all of my audio through. It came highly recommended by reviews in respected audio magazines. Honestly, my ears can’t tell a difference.

I'm sure many folks here could have a wonderful "debate" about such things, but I'm not surprised by your comments: If truth were only told, most honest engineers with perfect hearing would most likely agree with you in a blind listening test: they wouldn't be able to hear any difference either! :) In my opinion (and I'm sure there will be many differing opinions from folks here), some of that "highly recommended" equipment touted by those "respect audio magazines" is pure hype. When you see articles about how the metallic composition of your electrical power cables that plug the boxes into the wall can make a huge difference in how the violin sounds in some symphony or other, I just have to giggle a bit, and get out a very large pinch of salt.... In other words, I just don't bother with some of the outrageous claims made in some of audiophile magazines for the latest exotic material that you simply must have under your speaker cabinets, or the amazing sound that you'll get if only you'll buy the latest super-gizmo thingy.... To me, the ultimate goal of a studio sound system is NOT to make the music sound great. Not even to make it sound good, but rather to make it sound FLAT. In other words, to faithfully reproduce as exactly as possible whatever is stored on the medium. Just like the room, the sound system itself should not and cannot color the sound at all. It must reproduce everything, every instrument, every voice, every tone, with as flat a frequency response as you can possible get out of it, across the entire spectrum. Often when people hear a truly flat system for the the first time, they say "But it sounds so bland! So lifeless." And I say "Great! That's the way it is supposed to sound, in a studio." Flat is not interesting: it is truthful. Listening to flat response from a system and a room is about as interesting as looking at a blank piece of canvas before the artist starts painting on it: But that is the entire point! An artist could never paint a masterpiece if the canvas started out with patches of oil, ketchup, blood, vinegar, orange juice, attached to a warped frame, and with blue light shining on one part while red light shines on another part! That's the equivalent of trying to mix on a system with non-flat response in a room that colors the sound. You simply cannot expect the result to be any good, even with a grand master doing the "painting". That's my philosophy, anyway: the sound system should be flat, no EQ. The amps and speakers should have as flat a response as you can possibly afford, no color. And the room should have acoustics that are as neutral and natural as possible, no color. Does that sound "warm" and "enveloping" and "enthralling" and "amazing", like the audiophile magazines want to sell you? Nope. It sounds bland, white, neutral and uninteresting, which to my way of thinking is EXACTLY the way a studio should sound: Flat.

So, can a room be designed to serve all these purposes?

Yup! It sure can. No room can be perfect, just like no speaker can be prefect, but you sure can get it to be as good as your existing space and budget will possibly allow, if you base every part of it on the science of acoustics and physics, rather than on the "myths and memes" circulating on the internet, and repeated endlessly in some of those mags. - Stuart -

I don't see any of these intermittent sounds being a problem. Its nice and quite at this place.

OK, so you have your first design decision in place: Major isolation is not necessary.

If you're interested, here is how I built my last studio.

:shock: That was probably rather expensive, and definitely overkill! You have three-leaf and four-leaf MSM walls in there, which actually defeated part of what you were trying to do! But you made up for that with the extra mass, which is why you still got good isolation. You could actually have got the same level of isolation with about one third less of the materials that you used there, and at much lower cost... I'm sure it worked fine, but you spent more than you needed to, and used more materials than you needed to, and waste some space in your room. Please don't take that as criticism: Or rather, take it as constructive criticism There were some mistakes back there that you can fix this time around. You made those mistakes because you didn't know any better, but this time around there are plenty of folks here who are experts in the area of acoustics and construction, who will help you avoid making similar mistakes this time, and get you to a better studio for a lower cost. (I don't include myself in the "expert" category, by any means: I'm just a good parrot)

I'm not going to need anything this extensive at my new studio. I'm spending much more of my time and money on tuning the inside of the room.

Cool! Second design goal: A well-treated room.

If I get in there and have issues with sound coming in, I will deal with it down the road.

That might not be such a good idea, Mike. In order to improve your isolation "down the road", you'd have to tear out the treatment that you already had inside the room, since the isolation has to come first. You can't add isolation to a room without doing something to the walls that surround it, which means that you either have to tear down all the treatment inside the room, do the isolation, then put up new treatment, or you have to take off the outer leaf from around the outside of the room, and gain access to the wall interior like that. Either way is rather expensive and time consuming. Not to mention frustrating. To be honest, if you have the slightest doubt that you might need more isolation, then you should include it in the design right now. Adding an extra layer of drywall to each leaf in the initial build is just a tiny extra cost, a few dollars per square meter, as compared to trying to add it "down the road"...

Yes, very important!!! In my last studio, we had a separate air conditioning system installed for that room. The architect installed a bigger unit than was needed, used commercial ductwork which was lined with acoustical insulation. He made several “S” turns in order to keep sound from coming through. The cool air dropped quietly into the studio. It was extremely effective and I never heard it.

Excellente! That's exactly what you need. The only red flag there is the comment: "... installed a bigger unit than was needed". That usually isn't a good idea: You should install the exact correct unit that is needed. If you install a unit that is too large, then it does not cycle as often as it should: it cools the room fast, then turns off for a long while before cycling again, so it operates for less time than a correctly sized unit, meaning that it does not have a chance to dehumidify the air correctly. You could end up with more moisture in the air than is good for your, or for your equipment, or for your room. The unit should be dimensioned for your exact needs, taking into account everything about your build, neither too big nor too small.

Earlier this year, there was two feet of snow and ice outside but I was running the air conditioner in my studio.

Yup! I can believe that. I'm assuming that you also had fresh air ventilation in and out, in addition to the air conditioner itself? That's another issue that some home studio builders forget about. Your room will be hermetically sealed, and since you need to breath every now and then, you need fresh air coming in, and stale air going out. Since your previous place worked fine, you must have had that, but don't forget to include it here too!

The house has two units. The unit that I’m on only controls my studio, the kitchen and a living room. He is going to insulate the attic quite a bit more. The ductwork already has acoustical lining. He is going to add several turns in the ductwork before it reaches the unit.

Great. Sounds like he knows what he is doing. - Stuart -

If I built over the hallway space it would give me symmetry in the room and I would be able to hang a first reflection panel on the wall, as well as deal with bass traps in the newly created corner with the door. Comments?

Yup! Like Brien already said: that's what I would do. Block off that hallway if you can, with a good massive MSM wall. Maybe even brick it up. - Stuart -

I read it, and Wow! Thanks! Great article. I teach a basic "sound and acoustics" seminar for musicians in churches here in Chile, and the points you make are the same ones I make. Would you mind if I mentioned you and quoted from your article in my courses

No problem, go ahead, with my blessing. The reason I wrote this is to educate people about what will happen if they live a lifestyle like I used to. Actually, I think today's youth are going to end up a lot worse than me. Many of them are exposed to harmful sound levels, virtually around the clock.

If I get in there and have issues with sound coming in, I will deal with it down the road. That might not be such a good idea, Mike.

Point taken. Still, I really don't see this being a problem. I am taking the precaution of installing four solid core wood doors with acoustical seals, around the room. There will be two solid wood doors leading into the kitchen/house area. My studio will be separated from the living area of the house by the storage room and restroom which I think (hope) will provide the isolation needed on that side. The other two walls of the studio face either the garage or outside. I have had two people talk to me about using an "acoustic foam" as an insulation if needed, at a later date. To apply the insulation, a small hole is drilled, between each set of studs, up near the ceiling and filled up with acoustic foam which is said to be very effective. Do you have any knowledge of this foam? I am also being proactive in taking measures with the air conditioning system so that the air is silent coming into the studio and won't send sound back into the unit and rest of the house.

Yes, very important!!! In my last studio, we had a separate air conditioning system installed for that room. The architect installed a bigger unit than was needed, used commercial ductwork which was lined with acoustical insulation. He made several “S” turns in order to keep sound from coming through. The cool air dropped quietly into the studio. It was extremely effective and I never heard it. Excellente! That's exactly what you need. The only red flag there is the comment: "... installed a bigger unit than was needed". That usually isn't a good idea

The architect's reasoning here was: a "slightly bigger unit" doesn't have to work as hard to do the job, thus less whistling and undesirable noise, or noise of any kind for that matter. This was the best air conditioning system that I have ever seen in a studio. My only complaint was the dust factor it left in the studio. We are tweaking that problem in the new room with better filtering, efficiency, and return.

I'm assuming that you also had fresh air ventilation in and out, in addition to the air conditioner itself? That's another issue that some home studio builders forget about. Your room will be hermetically sealed, and since you need to breath every now and then, you need fresh air coming in, and stale air going out. Since your previous place worked fine, you must have had that, but don't forget to include it here too!

Already done! However, I do need to check (tomorrow) to see what will happen if I build a wall over the hallway entrance. I know that there is at least one air duct going inside that space (the bathroom). I need to see if it will be able to return in that newly sealed area. My air conditioning guy can advise me.

Okay, this drawing represents a scenario in which I built a wall over the hallway entrance. I've installed a door to give me access to the restroom and door leading outside. I would install a solid wood core door (acoustically sealed) near the corner as shown. Now, I believe my first reflection point on that right wall will be just to the right of the door. However, I still don't have complete symmetry, considering that three corners of the room have doors and the fourth corner (the one to my left when sitting in front of my monitor and speakers) is just a normal corner with no door. So, in this particular case, what would be the best way to treat these front corners? Should I mount a bass trap across the left corner and mount two separate 24 x 48 panels to the right side corner and door (respectively)? As stated earlier, I'm also uncertain of ability of the air conditioning system to return the air which will be in the newly closed off hallway, restroom. Thanks again for all the advise, especially Professor Stuart! I'd still like to have Ethan Winer chime in and shed some light if he's so inclined. Mike Myers

I do not have much to add other than congratulations on doing things right (see my signature line) and working with a great acoustician like Stuart. Impressed, Andre

I've been doing a lot of work this week on my design and thought I'd drop back in. Here is the original space, as it looks right now. Its a 22 x 15 foot room that has a hallway in the far right corner. Tile floor, sheetrock walls and ceiling.

Since hanging out here, I have decided to build a wall over the hallway and put a door there, in order to make the room symmetrical.

This image shows how I will set up my studio monitors. I am sitting 38% from the front wall and I am six inches to the left of center in the wide part of the room. My ears are 50 inches off the floor. I am aiming the axis of the speakers to a point 12 inches behind my head.