Home Studio Soundproofing: 3 Big Mistakes To Avoid To Reduce Noise - AcousticsInsider.com

hey what's up it's cesco from acousticsinsider.com again where i teach home studio acoustic treatment techniques for audio professionals but without all the voodoo now a question that i often get is what kind of things you can do to isolate your room better from the rest of the building or maybe from the second half of your room what kind of techniques you can use to sound proof your studio maybe you're dividing a single room into two because you want to share it with somebody else and you want to put up some sort of barrier so you can use both halves of the room separately or maybe you just want to make sure that you don't bother your family or the neighbors in the rest of the house maybe you've got a basement studio or an attic student you've got a staircase kind of leading up or leading down uh like an open staircase and you want to figure out if there's some something you can do to block sound from going down the staircase and into the rest of the house now a quick disclaimer before i get into it my expertise really is an acoustic treatment and not sound proofing not isolation techniques but i understand the basics well enough and i want to give you three big mistakes that i see people making when they think about isolation and the noise reduction and sound proofing so three big mistakes you want to avoid if you want to make sure that your efforts that you put into all this actually work so the first mistake i see people making is that they confuse sound proofing with acoustic treatment right so noise reduction noise isolation with treating the actual room they're not the same thing sound proofing or noise reduction is all about making sure that sound doesn't exit the room so it doesn't bother your neighbors or family or whatever and also that noise can't come into the room to bother you while you're working right and acoustic treatment is all about making the room itself sound good so just because you have good sound proofing good noise isolation from the rest of the building doesn't mean that the room itself sounds good a simple example to imagine this is just a concrete bunker you might have like a decoupled floating bunker which is perfectly isolated from the outside world but it still sounds like a bunker inside right so you've got excellent noise isolation in this case but no acoustic treatment so these are two different aspects of acoustics with completely different goals and that also means that the tools we use to reach those goals are completely different and that brings me to my second point or the second mistake that i see people making and that is that the materials you use for soundproofing for noise reduction need to reflect sound not absorb sound right so the tools that we use in acoustic treatment usually are meant to absorb sound but the tools that we use for isolation they actually need to reflect sound and the better they reflect sound the higher the isolation's going to be because ultimately what we want to do is create a barrier for sound not to go through and especially in lower frequencies that is going to be quite difficult so the more reflective a certain barrier is the better it is at also reflecting low frequencies which in turn basically means that the isolation is better the noise reduction through that barrier is higher so looking at some of the materials out there that people tend to jump to or tend to think about when trying to figure out what might work for isolation purposes first up heavy curtains right but a curtain is meant to absorb sound not reflect sound so it's not actually the right tool for isolation techniques it actually lets most of the sound pass through especially lower frequencies so it doesn't really work for our purposes where we're trying to isolate music right so uh sound that works across the spectrum a curtain might help a little bit with like higher frequencies with speech but even there just a tiny amount it might basically muffle really quiet voices but that's about it if you're trying to isolate the music from a whole band or from just music coming from your speakers a curtain isn't going to do much same with a carpet right a carpet absorbs sound it doesn't reflect sound so it's not going to help with isolation there's no point in putting down a carpet if you're trying to isolate yourself from the floor below it just doesn't work and the same with acoustic panels or insulation material the insulation material itself or the the porous material in the in the acoustic absorber panel is meant to as the name suggests absorb sound so again it's not the right tool for isolation purposes so what we need instead is a solid surface that reflects sound as best as possible and in order for that to work especially at lower frequencies we need mass right we need this thing to actually be a proper barrier against those huge wavelengths that you'll find in the lower frequencies that come in with a lot of energy right so basically what we need is a wall and the heavier the better and that brings me to my third mistake that i see people making and that is that they overestimate how well a certain solution actually works that they're looking at how much reduction in noise they might actually get from putting up that's that barrier let's have a quick look at this very simple spreadsheet calculator that calculates the transmission loss that you might get from a certain barrier assembly a certain wall assembly okay and this is actually taken from this book right here which is in german unfortunately but it's a very simple kind of idealized calculator that nicely illustrates what you might expect so what i'm showing you here is the effect a single layer of drywall will have right so very simple gypsum board which has a weight of roughly 1.2 pounds per foot squared so that's about 5.8 kilograms per meter squared and if i put this in this very simple calculator it shows us how much loss in sound pressure level we can expect at different frequencies right starting at 31.5 hertz up to the next octave of 63 hertz up to the next octave of 125 hertz and so on and all i want you to pay attention to is this one single black line which shows us the effect of that single layer of gypsum board and as we can see here it actually has zero effect at 31.5 hertz right so a single layer of gypsum board isn't going to stop low frequencies very low sub base frequencies at all but moving up to 63 hertz we get a transmission loss a reduction in sound pressure level through this barrier of maybe 5 to 6 db and then going up to 125 hertz that rises by another 6 db to about 12 db in total and in fact we we get this steady gradual increase of roughly 5 to 6 db per octave the thing to understand here is that a barrier won't have the same transmission loss across the spectrum it actually starts off the weakest or the the worst at lowest frequencies and then it generally increases in its effectiveness as you go up in the frequency spectrum that's something to just keep in mind whatever barrier you put up it's always going to be better at stopping sound at higher frequencies in comparison to lower frequencies and if you want any effect at lower frequencies at all you actually have to start with a pretty hefty wall ideally you want to put up two walls in fact and very roughly said you could argue that you will get an increase in transmission loss aka how much sound goes through the wall or how how large the reduction is rather you get an increase by about 6 db with every doubling of mass so starting with this single layer of gypsum board at 1.2 pounds per foot squared if you double that to 2.4 pounds per foot squared you'll go from 6 db over noise reduction at 63 hertz up to about 12 db at 63 hertz if you want to double that again if you want to get 18 db of noise reduction at 63 hertz you have to double that again so you have to jump from 2.4 pounds per foot squared to 4.8 pounds per foot squared and so on and so forth so as you can see it actually becomes increasingly difficult to stop lower frequencies the higher your demand is basically the the more isolation you want to get right and again we're talking jumps of 6 db here compare that to literally just turning down the volume of your system as you're working by 6 db so let me just play a quick side tone at 63 hertz for you i'm going to reduce it by 6 db just as a quick example so you can hear what doubling the thickness of your wall will do in terms of improving the reduction of volume right so that's all you're gonna get from doubling the mass of the the barrier that you put up and you can see just how much it takes to actually stop sound but going back to our little diagram here this actually only describes the sound reduction the the reduction in in sound pressure level you'll get from the barrier itself this isn't talking about the sound reduction you'll get in the room that the the barrier is trying to protect the reason is that sound loves to travel through the actual building material so if noise is coming from another room it'll actually enter the wall go through the construction material go around this one barrier that you've put up and come out of all the other walls that aren't covered by the barrier so in practice you won't actually get a reduction as predicted by this simple spreadsheet because sound can actually go around the barrier and still get into the room that's what makes it even more difficult and that's why ultimately if you really want to get this right you have to look at room and room constructions where every single surface has a barrier like this to protect it from sound transmitting getting transmitted through it right so in practice putting up a single barrier always has limited use and that's really a bummer a bummer of a realization because you can put in a lot of effort to put up a single very well-built structure but its use is still going to be so so so unfortunately proper isolation proper noise reduction that works in a studio even a home studio is always expensive and time-consuming and very invasive to the room that you're trying to improve especially if you want to take it to that level where you can work at night for example without bothering your family or your neighbors the truth is there is no cheap way to get proper soundproofing functional noise reduction that works with full range music it's just not possible if you actually want it to work you have to do it right so if you're looking at soundproofing options right now make sure you always remember those three mistakes okay so first of all soundproofing is not the same as acoustic treatment you can't look at acoustic treatment tools for the job of soundproofing and noise reduction and in order to distinguish between the two you can always ask yourself is this thing that i'm looking at reflecting or absorbing if it's absorbing then it's made for acoustic treatment and it's not right for your purposes if it is reflective the question is how much and in order to get enough reflection especially at low frequencies you really need a lot of mass and even then make sure you're realistic about what you can expect to happen the amount of reduction is always going to be higher in the high frequencies and it's going to drop off towards the low frequencies and this is especially true if you don't have an option to put in a proper wall or you're just not willing to do it right now if you're actually going to put up a curtain as a barrier between two rooms let's say or to section off the staircase just make sure you understand what you can expect to happen it's just not going to work at low frequencies and even at high frequencies it might just reduce it by a very small amount now what i tend to recommend is when people come and ask me about what they can do to isolate the room better is to if nothing else making sure that the room is air tight right because sound is going to go through even the tiniest cracks and holes that you can't even see and completely ruin any chance of isolation and this concerns especially doors and windows if they don't close properly if there are gaps if the seal isn't right that's going to let sound through like nothing else so what you could do for example is play some white noise outside of the the door or the window and maybe just with one ear holding one ear shut and with the other ear you just go along the seam of the door and the window to check where sound is coming through and then it's those spots where you need to put in some work to make sure it seals airtight and obviously that means looking at changing out the weather stripping or it means sealing up any edges or corners with caulk or silicone by the way you always want to make sure that it dries flexible right so the stuff needs to still have some flexibility once it's dried okay so i if i've successfully brought you off of the idea of using a curtain make sure that the room is airtight if nothing else that's going to give you a useful improvement in terms of noise reduction and by the way if you're currently setting up a new room one of the most tricky things to really grasp to understand is where you need to place your setup like which side in your room to face and where exactly your listening position needs to be and this is especially the case if you're dealing with like a really odd shaped room that isn't just a perfect square because at that point all these guidelines about just like facing the short side and maybe placing your listening position at 38 of the room's length those obviously don't work so what do you do in those scenarios well exactly for these kind of rooms i've developed a special listening test that will help you figure out where you need to place your listing position and which side in your room you really want to face i call it the base hunter technique and you can download it for free at the link in the description because in the end you don't get to pick where your listening position needs to be the room is going to dictate that for you and it's your job to find out where that actually is in the end it all comes down to standing waves or room modes and the particular pattern of room modes and standing ways that your room has what you want to make sure is you sit in the spot where the balance between all those standing waves gives you the most even low end response so again if you're currently setting up a new studio you're trying to figure out where to best place your listening position which side to face where to place your setup make sure you download the guide to the base hunter technique in the description in order to figure out where the ideal listening position in your room actually is but that's it for now thanks for watching as always i'll see you in the next video

Channel: Acoustics Insider

Views: 83,349

Keywords: home studio soundproofing, 3 mistakes to avoid, noise reduction, isolation, home, project, studio, acoustics acoustic treatment, sound proofing, room treatment, music studio, recording studio, mix room, garage studio, attic studio, bedroom studio, recording room, drum room, room acoustics, acoustics, DIY acoustics, acoustics insider, acousticsinsider

Id: Et7xva8KZN0

Length: 17min 6sec (1026 seconds)

Published: Tue Sep 15 2020