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-   -   I'm tryna build something crazy - would like input pleez (https://www.gearslutz.com/board/studio-building-acoustics/1283250-im-tryna-build-something-crazy-would-like-input-pleez.html)

gear_slut007 16th October 2019 03:34 AM

I'm tryna build something crazy - would like input pleez
 
I want to build something crazy. Sorta pretty much I want to call it an "isolation chambering for mixing". I don't want to be a TL;DR situation so I will be brief and vague for now(I still need to make a few sketches and I will share them here or on my blog soon enough but in the mean time). Basically, I have a lot of extra room where I am living right now because I moved but the walls are paper thin so no MIXING, TRACKING or COMPOSING in my room on any speakers (not the 3 inch or the eris 8") So I want to build an elevated room inside my room as such it will not come in contact with the wall, ceiling or floors directly. Thinking 5 feet x 5 feet and just large enough to sit in. I plan to build it so it is modular so I can bring it when I move (already got some ideas there) but need help picking supplies maybe because I don't have much experience building these kinds of things. Once it is complete It will be outfitted with a seating area for 2 people max and a small desk just far enough away to mix good considering the space.

TL;DR I really need help picking the best materials for creating a sound proof box (this thing needs to be 100% sound proof, seriously).

Soundman2020 16th October 2019 06:05 AM

Quote:

(this thing needs to be 100% sound proof, seriously).
Ummm.... 100% soundproof is impossible, actually. The laws of physics don't allow that. There is no barrier that can provide infinite isolation, so any conceivable sound cannot be stopped by any conceivable barrier.

What you CAN do, is to isolate to a high level. But you need to define that level! You can't build something without knowing what the target is! So the first thing you should do, is to define how much isolation you need. To do that, you need to provide two numbers: "How loud are you?" and "How quiet to you need to be?".

To measure the first number, just set upa a typical session of you doing whatever it is you will normally do in your room, ad measure how loud that is using an ordinary hand-held sound level meter, set to "C" weighting and "Slow" response. Be as loud as you ever would be, and look at he meter. It will tell you how many decibels you are producing. Then stop making any noise, wait until the very quietest time of day or night, when there's very little background noise around at all, and measure the level again with your meter. Now you have answered the second question as well. So you have two numbers: one is "How loud", and the other is "How quiet". Subtract the second number form the first one, and that tells you how much isolation you need, in decibels, to get really good isolation, such that whatever noise you make inside your room, for people listening outside, they would hear it very, very quiet, at the same level as the background noise.

It's that simple.

With that number in hand, you can now look at the usual tables, graphs, books, and research, to find a construction method that will provide the amount of isolation you need. Here's a link to a list of several documents that tell you all about the various types of walls, floors, ceilings, windows, doors, and other parts that you'll need to build, and how much each of those can isolate: Useful documents about sound isolation

Getting very high isolation is pretty difficult, and expensive, so it's important to get your numbers right! There's a very large difference in cost between isolating a room for 40 dB and isolating the same room for 60 dB. For a typical room, you can probably get 40 dB isolation for a few thousand dollars, but to get 60 dB you would need many tens of thousands of dollars. 70 db is getting into the region of several hundreds of thousands of dollars... So getting your number right is pretty important!

What you want to do actually isn't crazy: its called the "room in a room" approach to isolation, and its the way things are normally done. What you want is the same as what most studio builders want: High isolation. The only thing crazy about it, is how much money it costs, and how much building materials it takes! That0s cazy, but the concept isn't crazy, when done right. There are well-known, well-documented, well-tested, proven, methods for doing what you want. Its just a matter of defining your number carefully, then looking at the documentation to find something that can produce that number.

There's a few other things that aren't right about your initial plans, but first get the isolation issue sorted out, then you can look at the other issues.


- Stuart -

kgveteran 16th October 2019 05:33 PM

You’ll need to transfer air for breathing, keeping as many electronics out of said room too would help.
I just built a 600lb rolling acoustically sealed door for my room, with enough planning, anything is possible !!!!

gear_slut007 17th October 2019 12:51 AM

Quote:

Originally Posted by Soundman2020 (Post 14267647)
Ummm.... 100% soundproof is impossible, actually. The laws of physics don't allow that. There is no barrier that can provide infinite isolation, so any conceivable sound cannot be stopped by any conceivable barrier.

What you CAN do, is to isolate to a high level. But you need to define that level! You can't build something without knowing what the target is! So the first thing you should do, is to define how much isolation you need. To do that, you need to provide two numbers: "How loud are you?" and "How quiet to you need to be?".

To measure the first number, just set upa a typical session of you doing whatever it is you will normally do in your room, ad measure how loud that is using an ordinary hand-held sound level meter, set to "C" weighting and "Slow" response. Be as loud as you ever would be, and look at he meter. It will tell you how many decibels you are producing. Then stop making any noise, wait until the very quietest time of day or night, when there's very little background noise around at all, and measure the level again with your meter. Now you have answered the second question as well. So you have two numbers: one is "How loud", and the other is "How quiet". Subtract the second number form the first one, and that tells you how much isolation you need, in decibels, to get really good isolation, such that whatever noise you make inside your room, for people listening outside, they would hear it very, very quiet, at the same level as the background noise.

It's that simple.

With that number in hand, you can now look at the usual tables, graphs, books, and research, to find a construction method that will provide the amount of isolation you need. Here's a link to a list of several documents that tell you all about the various types of walls, floors, ceilings, windows, doors, and other parts that you'll need to build, and how much each of those can isolate: Useful documents about sound isolation

Getting very high isolation is pretty difficult, and expensive, so it's important to get your numbers right! There's a very large difference in cost between isolating a room for 40 dB and isolating the same room for 60 dB. For a typical room, you can probably get 40 dB isolation for a few thousand dollars, but to get 60 dB you would need many tens of thousands of dollars. 70 db is getting into the region of several hundreds of thousands of dollars... So getting your number right is pretty important!

What you want to do actually isn't crazy: its called the "room in a room" approach to isolation, and its the way things are normally done. What you want is the same as what most studio builders want: High isolation. The only thing crazy about it, is how much money it costs, and how much building materials it takes! That0s cazy, but the concept isn't crazy, when done right. There are well-known, well-documented, well-tested, proven, methods for doing what you want. Its just a matter of defining your number carefully, then looking at the documentation to find something that can produce that number.

There's a few other things that aren't right about your initial plans, but first get the isolation issue sorted out, then you can look at the other issues.


- Stuart -

This. You are very smart, I also agree there are other flaws in my initial post however for the sake of being as brief as I felt was reasonable I didn't include all of my details on my plans to account for all of them but I do appreciate you for your honestly and pointing that out... but I definitely was super confused on how to go about determining requirements for sound proofing and this just made so much sense. Thank you certainly

gear_slut007 17th October 2019 12:55 AM

Quote:

Originally Posted by kgveteran (Post 14268570)
You’ll need to transfer air for breathing, keeping as many electronics out of said room too would help.
I just built a 600lb rolling acoustically sealed door for my room, with enough planning, anything is possible !!!!

I am already concocting some plans for air flow in and out, I will share those details hopefully as surely as I build this thing but yes I plan on doing something about that. I also plan to have no more than 2 monitors, a midi keyboards, and either a laptop or display, keyboard and mouse in there at any one time... I pray your door never falls on anyone

Maniac 7777 17th October 2019 01:15 AM

Make floor out of cinder blocks going into wood slots for alignment. suspend framed blocks on used tires and blankets. Build another floor on top of this one that does not touch any walls. Add the walls and ceiling atop suspended floor. Add a duct with articulating cap to kill air conditioning noise when necessary. Bolt the whole thing together with Allen Bolts so you can Break it down and move when necessary.

Love and Light,
93 93/93

Soundman2020 17th October 2019 01:29 AM

Quote:

Make floor out of cinder blocks going into wood slots for alignment. suspend framed blocks on used tires and blankets.
What would the resonant frequency of that assembly be? It seems like it would be rather high. Used tires and blankets are not very resilient... How do you even calculate the spring constant for a used tire or a blanket?

- Stuart -

gear_slut007 17th October 2019 02:44 AM

Quote:

Originally Posted by Soundman2020 (Post 14269452)
What would the resonant frequency of that assembly be? It seems like it would be rather high. Used tires and blankets are not very resilient... How do you even calculate the spring constant for a used tire or a blanket?

- Stuart -

What do you suppose the resonant frequency of a frame made of 4x4s would be? Granted I used about 200 lbs of them and made a very robust base about 5x5x2feet in dimension?

Maniac 7777 17th October 2019 03:35 AM

Quote:

Originally Posted by Soundman2020 (Post 14269452)
What would the resonant frequency of that assembly be? It seems like it would be rather high. Used tires and blankets are not very resilient... How do you even calculate the spring constant for a used tire or a blanket?

- Stuart -

Dude you are a freaking Venture Capitalist, acoustical engineering god. and I see you know the twins Apollo and Artemis. Why are you commenting on my peon Brooklyn Basement floated floor? I knew you were a bully, sheesh. You must be a Billionaire Dude.

Love and Light 93 93/93

gear_slut007 17th October 2019 04:24 AM

Quote:

Originally Posted by Maniac 7777 (Post 14269582)
Dude you are a freaking Venture Capitalist, acoustical engineering god. and I see you know the twins Apollo and Artemis. Why are you commenting on my peon Brooklyn Basement floated floor? I knew you were a bully, sheesh. You must be a Billionaire Dude.

Love and Light 93 93/93

Do you actually have this setup that you are talking about? Also, to be fair... he isn't out of place factually whatsoever and what he said is not that freaking crazy and can be approached quite simply from anyone willing to use a little brain power to approach it, like literally he covered alot but barely even broke the surface of the stuff for you to grant him such a title. Anyone can get it. I am not sure I am too familiar with the spring constant (although I assume he is talking to something to do with the tires being quite booyant and **** possibly producing ill effects and doing little to effect any sound) but resonant frequency is something to take very seriously. We do it all the time with out even noticing it. But basically what he is saying that light materials bad, heavy materials good. Porous materials not so good, dense materials probably better because the frequency at which they will resonate is lower. Everything in the world has a resonant frequency and when anything is exposed to it's resonant frequency it will experience certain phenomena mostly meaning it will start to produce excess vibrations itself thus defeating the properties of the noise cancellation for a given frequency band and harmonics and also exaggerating all sounds of a similar frequency in close proximity. An example of this is if your studio monitors resonant frequency is 33 hz (kinda low for a studio monitor to reproduce but more or less realistically feasible for a studio monitors resonant frequency) and that you are also making some music and decide to write a bass line using the C1 note (C1 note freq is 33hz and also that is for the most part an incredibly low note to being playing and not likely anyway), in theory the listener experiencing the sound would be exposed to a boosted representation of the bass line because the entire monitor itself would vibrate by nothing more than being exposed to it's resonant frequency and begin moving it's self (I say in theory because their are more variables at play here than just this stuff, IE amplifier and load etc). And so if you didn't know audible sound generally ranges from ~20hz ish i believe to some number around or above 20Khz (maybe higher say scientist) but also most studio monitors even in the 8 inch class struggle at producing bass frequencies at that level accurately so your bass is likely to be mute before it is to do this in a noticeable way unless you are applying an ungodly amount of EQ and as a result really driving your amps to push in the low end (probably slowly killing them)

Also I actually think this is a kinda sick idea for a jam room or something but I just need an incredibly small sound proof space for mixing and studio monitors that is as neutral as possible acoustically

Anyone please correct me if anything here is f'ed up beyond reconciliation I am doing my best...

Soundman2020 17th October 2019 07:26 AM

1 Attachment(s)
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I am not sure I am too familiar with the spring constant (although I assume he is talking to something to do with the tires being quite booyant and **** possibly producing ill effects and doing little to effect any sound) but resonant frequency is something to take very seriously.
You have the basic idea.

It works like this: If you want to "float" a structure (any structure) so that it can't transmit vibrations into whatever it is sitting on (which is what you are trying to do with your "room in a room" that you mentioned), then you need to be sure that it really does "float"! By "float", I mean that it is decoupled from the base that it is sitting on, sort of like a boat is "decoupled" from the river bed under it, by all that water. The boat can rise and fall on the waves, completed unaffected by the river bed. You are trying to do the same with your isolated room: you want it to "float" in the same way as that boat, so that any "rising and falling" from vibrations in the room, cannot get down to the base.

OK, that's the concept, and it's simple to understand in principle.... but its a bit more complex in practice, as you already figured out!

Here's the thing: an object can only float if the "thing" that it is floating on is "soft" enough (water, for the case of the boat, rubber for your room), and it can only float for vibrations above a certain frequency. There is always a lower limit to the frequencies that it can isolate. That limiting frequency is the natural resonant frequency of the object (your room) along with the rubber. It's a resonant system, and it resonates at a specific frequency. In simple physics, it is a "Mass-Spring" system. Just like a weight sitting on a spring. There are very simple mathematical equations for calculating the frequency, and the only two things you need to know are how heavy the mass is, and how "springy" the springy is. That's what the "spring constant" is all about. Its the technical term for "springiness". That's why I asked what the spring constant was, in that earlier suggestion. Because if the spring is too "hard" (not springy enough), then the boat won't float!

Think of this: if you have a heavy weight sitting on a spring, and the weight is so heavy that it squashes the spring completely flat, then obviously, that isn't going to float! Its not going to isolate. Also, if the weight is so light that the spring isn't compressed at all (maybe with just a feather on it), then it also won't float... and it won't isolate. You have to use just the right type of spring for the weight, in order to make it "float". In fact, you need to use a spring that will compress by about 10% to 30%. If it compresses more than 30%, then it doesn't float. If it compresses less than 10%, it doesn't float. And that range also depends on the type of spring: for example, neoprene rubber has a different range than EPDM rubber, Sorbothane rubber yet another range, and a steel spring is different again.

As you can see, it's not just as simple as putting any old spring under any old weight! there's math and physics to think about, equations to do. It is very important to get the right spring for the weight of your room. If not, then either your room will over-compress the spring, and it will "bottom out", meaning that it doesn't isolate... or it will "under-compress" the spring, so it "tops out", and it won't float... and won't isolate. You have to get it right, if you want your room to actually be isolated.

It would be rather sad if you spent all that time and money and effort to build your floating room, then when it is finished you find that it does not actually isolate, because the spring you used was too hard, or too soft...

If you look at YouTube, you'll find a whole bunch of videos there of people who are trying to float their rooms with a couple of 2x4s resting on rubber pads, and a plywood deck on top... thinking that they are "floating their floor"... then at the end wondering why their room sounds like garbage, and the neighbors are still complaining! The sad truth is, that in order to float a floor properly, you need a huge amount of mass, and the exact right spring. 2x4 joists on rubber pucks is way, way short of what is needed. I'm posting a graph below that shows the actual, real, true, tested, situation, not YouTube fantasy. You can see for yourself why bits of rubber and 2x4's don't work.

That graph is for the case where you use air as the spring. Air is actually a great spring, believe it or not: far better than a coil of steel, or a piece of rubber. It is much "softer", and that's a GOOD thing! You want the spring to be as soft as possible. The harder the spring, the less it isolates.

So, the graphs shows four different curves, for four different weights ("psf" means "Pounds per Square Foot"). On the left side, it shows the resonant frequency that you would get for various combinations. As you already realized, what you need is to get your resonant frequency lower than the lowest frequency that you'll have in the room. In fact, for complex mathematical reasons, you need to get the resonant frequency one octave lower, which means half the frequency. You used the example of 33 Hz, which is very valid, so let's go with that: if you need to isolate frequencies at 33 Hz, then you need to make sure that the resonant frequency of your floor is less than half of that, or less than 16.5Hz. So look at the left side of the graph, locate the spot where 16.5 Hz is (call it half way between 10 Hz and 20 Hz), and draw an imaginary line across the chart there. You can immediately see that your line will NEVER meet the curves for 5 psf or 10 psf, and only just touches the curve for 30 psf, way over at the far right. So the only real option you have, is the last curve: 60 psf. Your line will hit that somewhere around the middle of the graph, at roughly the 3.0 mark. So, that means that if you ONLY used air as the spring under your floor (large air bags filled with compressed air, for example), you would need to have 3" thickness of air... and you would also need to have a floor that weights 60 pounds per square foot! So if your room is 100 square feet, the floor would have to weigh six thousand pounds! That's what you'd need for 60 psf. Now, consider that a sheet of really thick 3/4" plywood weighs about 3 pounds per square foot... I think you see the problem! You would need TWENTY LAYERS of 3/4"plywood to get enough mass on your floor! Now you can understand why those folks on YouTube don't have much success... The only reasonable way to get enough weight there, is by making a 4" thick reinforced concrete slab. Concrete is about 4 times more dense than plywood, so it can be one quarter the thickness for the same total weight.

OK, that's for an air spring: what about a rubber spring? Or a steel spring? That's a bit more complicated, but it turns out that you still need a huge amount of mass to make it work... and there's one other important point here: Even if you use rubber pads under your floor, you still have an air gap down there! And the same graph applies to that air gap! In fact, you need a larger air gap now, because the rubber and the air are in parallel, and the rubber is a worse spring than the air, so you need to have more of both, and softer rubber, to make it work.

Yes, it's complex. Floating a floor, or a room, is a Big Deal. It can't be done successfully by just putting down some random bits of rubber thingies with a wooden deck on top! There's no way that can work. For people who do know how to float a floor and how to do the math, suggestions of rubber pucks, tennis balls, bicycle inner tubes, and other types of rubber, are just plain silly. Especially when the floor on top of that is just a layer or two of plywood with some laminate flooring, or vinyl tiles on it! It's a joke in bad taste. Anybody who actually did that in real life will end up with a failure: a floor that does not float, and is probably illegal anyway! There's a thing called "building codes", which are laws and regulations that govern how you are allowed to build something. Putting unapproved materials under your floor is going to cause you major problems with that!

Ok, so getting back on track: floating your floor, or your entire room, might not even be necessary. The vast majority of home studios do NOT have floated floors... Firstly because it is usually not needed, secondly because it is really, really hard to do right (as you can see from the very simple explanation above), thirdly because you need a huge amount of weight.... that your current floor probably could not handle anyway, and would collapse... and fourthly, because it is insanely expensive to do it.

Let's start by figuring out if you even need to think about floating your floor, and if it is physically possible to do that: What type of floor do you have at present? Is it a concrete slab? A wooden floor? Something else? And what is underneath that floor? Does it rest directly on the ground, or is there another room down there below you?

If you have a wooden floor, then it is pretty much impossible to float your studio, as a wooden floor would not be able to support the huge weight of a fully floated studio. Even if you have a concrete floor, it still might not be possible, if you are on an upper floor with other rooms below you: even concrete has limits. You would have to hire a structural engineer to come take a look at your place, and tell you how much additional weight you could safely put on that floor. The only time you would probably be OK, is if your floor is a concrete slab that sits directly on the ground. And it that is the case, then you don't need to float the room in any case! A concrete slab on grade is an excellent studio floor, with good isolation all by itself, so there would be no need to float your room.

So that's the situation: You probably don't need to float, or cannot float anyway, so I would not bother wasting too much time on that. Rather, look at what you CAN do, which is to build your room such that the walls, ceiling, windows, doors, electrical system, and HVAC system are all isolated. You can still get good isolation for your studio like that, even without floating the floor.

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But basically what he is saying that light materials bad, heavy materials good.
Yep! Exactly.

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Everything in the world has a resonant frequency and when anything is exposed to it's resonant frequency it will experience certain phenomena mostly meaning it will start to produce excess vibrations itself thus defeating the properties of the noise cancellation for a given frequency band and harmonics and also exaggerating all sounds of a similar frequency in close proximity.
Exactly! Spot on! You obviously already understand a lot of this stuff. So it's just a matter of figuring out how to put that into practice, to isolate your room.

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And so if you didn't know audible sound generally ranges from ~20hz ish i believe to some number around or above 20Khz (maybe higher say scientist) but also most studio monitors even in the 8 inch class struggle at producing bass frequencies at that level accurately so your bass is likely to be mute before it is to do this in a noticeable
Right. The audio range is generally considered to be 20 Hz to 20 kHz. There's actually not much going on at the extremes: the only two instruments that get down below 30 Hz, are the cathedral organ, and the concert grand piano: It's more realistic to think of the lower limit as maybe 28 Hz or so (a six-string bass gets down to about 31 Hz).

That said, even though small speakers don't have good specs for low frequency, they can still put out a lot of energy below their so-called "cut-off" frequency. A speaker where the spec says it goes down to 40 Hz, for example, could still put out a fair amount of power even at 20 Hz, which is only one octave lower.

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unless you are applying an ungodly amount of EQ and as a result really driving your amps to push in the low end (probably slowly killing them)
Right! And if you do that, then your mixes sound terrible when you play them any other place outside the room!

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I just need an incredibly small sound proof space for mixing and studio monitors that is as neutral as possible acoustically
Those two concepts don't go together, unfortunately. You can't have a really small room that is acoustically good for mixing. That's sort of like wanting a bottle of water that is dry, or a match that burns cold... :) In order to get the neutral sound that a control room must have (you are totally right about that: it must be neutral), then room has to be large enough for the acoustics to work. The specs for pro control rooms say that you need at least 215 square feet of floor space, to do that. Now, don't get too worried: you can actually get decent sound in a room that is smaller than 215 ft2: it's just easier to do it if the room is bigger. I have done rooms down to about 110 ft2 that turned out quiet successfully. But I would not go much smaller than that. The smaller it is, the harder it is to treat, and the less good the final result will be. Once again, it's all about the laws of physics... there are limits on what can be accomplished. So make your room as big as you can.

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Anyone please correct me if anything here is f'ed up beyond reconciliation I am doing my best...
You are doing fine! :) You are asking the right questions in the right place, and you already have a good grasp of some of the concepts. It's just a matter of working through the right procedure now, step by step, and things will start to make a lot more sense.

- Stuart -

RyanC 17th October 2019 02:34 PM

Quote:

Originally Posted by gear_slut007 (Post 14267540)
Thinking 5 feet x 5 feet and just large enough to sit in.

This is really small and the dimensions are not favorable, a room this size will have poor acoustics. A lot posted in this thread already but it seems to be mostly about isolation. It's worth noting that with this small of a room and 5x5 footprint, no room for significant treatment, I think you would likely be better off with headphones.

lynngraber 17th October 2019 02:53 PM

I am sure you've thought of this, but what about a nice pair of headphones? The idea you can't mix on headphones is BS.

RyanC 18th October 2019 04:48 AM

This is a thread with someone doing the same thing, actually slightly larger-

Building a small 6x6 air-tight cockpit for producing, recording, and mixing

If you don't want to read the whole thing, here is a quote that pretty well sums it up-

So, in the end, of course you all were right. It's acoustically reprehensible. I won't be able to get finished mixes out of it at all. But I honestly am very satisfied it turned out the way it did because I have a much deeper appreciation for acoustic setup and I will be paying much closer attention to that the rest of my career. And I also have a tricked out little vocal booth where I can hole myself up and get some serious creative juices flowing.

VenVile 18th October 2019 11:57 AM

Quote:

Originally Posted by Soundman2020 (Post 14269805)
You have the basic idea.

It works like this: If you want to "float" a structure (any structure) so that it can't transmit vibrations into whatever it is sitting on (which is what you are trying to do with your "room in a room" that you mentioned), then you need to be sure that it really does "float"! By "float", I mean that it is decoupled from the base that it is sitting on, sort of like a boat is "decoupled" from the river bed under it, by all that water. The boat can rise and fall on the waves, completed unaffected by the river bed. You are trying to do the same with your isolated room: you want it to "float" in the same way as that boat, so that any "rising and falling" from vibrations in the room, cannot get down to the base.

OK, that's the concept, and it's simple to understand in principle.... but its a bit more complex in practice, as you already figured out!

Here's the thing: an object can only float if the "thing" that it is floating on is "soft" enough (water, for the case of the boat, rubber for your room), and it can only float for vibrations above a certain frequency. There is always a lower limit to the frequencies that it can isolate. That limiting frequency is the natural resonant frequency of the object (your room) along with the rubber. It's a resonant system, and it resonates at a specific frequency. In simple physics, it is a "Mass-Spring" system. Just like a weight sitting on a spring. There are very simple mathematical equations for calculating the frequency, and the only two things you need to know are how heavy the mass is, and how "springy" the springy is. That's what the "spring constant" is all about. Its the technical term for "springiness". That's why I asked what the spring constant was, in that earlier suggestion. Because if the spring is too "hard" (not springy enough), then the boat won't float!

Think of this: if you have a heavy weight sitting on a spring, and the weight is so heavy that it squashes the spring completely flat, then obviously, that isn't going to float! Its not going to isolate. Also, if the weight is so light that the spring isn't compressed at all (maybe with just a feather on it), then it also won't float... and it won't isolate. You have to use just the right type of spring for the weight, in order to make it "float". In fact, you need to use a spring that will compress by about 10% to 30%. If it compresses more than 30%, then it doesn't float. If it compresses less than 10%, it doesn't float. And that range also depends on the type of spring: for example, neoprene rubber has a different range than EPDM rubber, Sorbothane rubber yet another range, and a steel spring is different again.

As you can see, it's not just as simple as putting any old spring under any old weight! there's math and physics to think about, equations to do. It is very important to get the right spring for the weight of your room. If not, then either your room will over-compress the spring, and it will "bottom out", meaning that it doesn't isolate... or it will "under-compress" the spring, so it "tops out", and it won't float... and won't isolate. You have to get it right, if you want your room to actually be isolated.

It would be rather sad if you spent all that time and money and effort to build your floating room, then when it is finished you find that it does not actually isolate, because the spring you used was too hard, or too soft...

If you look at YouTube, you'll find a whole bunch of videos there of people who are trying to float their rooms with a couple of 2x4s resting on rubber pads, and a plywood deck on top... thinking that they are "floating their floor"... then at the end wondering why their room sounds like garbage, and the neighbors are still complaining! The sad truth is, that in order to float a floor properly, you need a huge amount of mass, and the exact right spring. 2x4 joists on rubber pucks is way, way short of what is needed. I'm posting a graph below that shows the actual, real, true, tested, situation, not YouTube fantasy. You can see for yourself why bits of rubber and 2x4's don't work.

That graph is for the case where you use air as the spring. Air is actually a great spring, believe it or not: far better than a coil of steel, or a piece of rubber. It is much "softer", and that's a GOOD thing! You want the spring to be as soft as possible. The harder the spring, the less it isolates.

So, the graphs shows four different curves, for four different weights ("psf" means "Pounds per Square Foot"). On the left side, it shows the resonant frequency that you would get for various combinations. As you already realized, what you need is to get your resonant frequency lower than the lowest frequency that you'll have in the room. In fact, for complex mathematical reasons, you need to get the resonant frequency one octave lower, which means half the frequency. You used the example of 33 Hz, which is very valid, so let's go with that: if you need to isolate frequencies at 33 Hz, then you need to make sure that the resonant frequency of your floor is less than half of that, or less than 16.5Hz. So look at the left side of the graph, locate the spot where 16.5 Hz is (call it half way between 10 Hz and 20 Hz), and draw an imaginary line across the chart there. You can immediately see that your line will NEVER meet the curves for 5 psf or 10 psf, and only just touches the curve for 30 psf, way over at the far right. So the only real option you have, is the last curve: 60 psf. Your line will hit that somewhere around the middle of the graph, at roughly the 3.0 mark. So, that means that if you ONLY used air as the spring under your floor (large air bags filled with compressed air, for example), you would need to have 3" thickness of air... and you would also need to have a floor that weights 60 pounds per square foot! So if your room is 100 square feet, the floor would have to weigh six thousand pounds! That's what you'd need for 60 psf. Now, consider that a sheet of really thick 3/4" plywood weighs about 3 pounds per square foot... I think you see the problem! You would need TWENTY LAYERS of 3/4"plywood to get enough mass on your floor! Now you can understand why those folks on YouTube don't have much success... The only reasonable way to get enough weight there, is by making a 4" thick reinforced concrete slab. Concrete is about 4 times more dense than plywood, so it can be one quarter the thickness for the same total weight.

OK, that's for an air spring: what about a rubber spring? Or a steel spring? That's a bit more complicated, but it turns out that you still need a huge amount of mass to make it work... and there's one other important point here: Even if you use rubber pads under your floor, you still have an air gap down there! And the same graph applies to that air gap! In fact, you need a larger air gap now, because the rubber and the air are in parallel, and the rubber is a worse spring than the air, so you need to have more of both, and softer rubber, to make it work.

Yes, it's complex. Floating a floor, or a room, is a Big Deal. It can't be done successfully by just putting down some random bits of rubber thingies with a wooden deck on top! There's no way that can work. For people who do know how to float a floor and how to do the math, suggestions of rubber pucks, tennis balls, bicycle inner tubes, and other types of rubber, are just plain silly. Especially when the floor on top of that is just a layer or two of plywood with some laminate flooring, or vinyl tiles on it! It's a joke in bad taste. Anybody who actually did that in real life will end up with a failure: a floor that does not float, and is probably illegal anyway! There's a thing called "building codes", which are laws and regulations that govern how you are allowed to build something. Putting unapproved materials under your floor is going to cause you major problems with that!

Ok, so getting back on track: floating your floor, or your entire room, might not even be necessary. The vast majority of home studios do NOT have floated floors... Firstly because it is usually not needed, secondly because it is really, really hard to do right (as you can see from the very simple explanation above), thirdly because you need a huge amount of weight.... that your current floor probably could not handle anyway, and would collapse... and fourthly, because it is insanely expensive to do it.

Let's start by figuring out if you even need to think about floating your floor, and if it is physically possible to do that: What type of floor do you have at present? Is it a concrete slab? A wooden floor? Something else? And what is underneath that floor? Does it rest directly on the ground, or is there another room down there below you?

If you have a wooden floor, then it is pretty much impossible to float your studio, as a wooden floor would not be able to support the huge weight of a fully floated studio. Even if you have a concrete floor, it still might not be possible, if you are on an upper floor with other rooms below you: even concrete has limits. You would have to hire a structural engineer to come take a look at your place, and tell you how much additional weight you could safely put on that floor. The only time you would probably be OK, is if your floor is a concrete slab that sits directly on the ground. And it that is the case, then you don't need to float the room in any case! A concrete slab on grade is an excellent studio floor, with good isolation all by itself, so there would be no need to float your room.

So that's the situation: You probably don't need to float, or cannot float anyway, so I would not bother wasting too much time on that. Rather, look at what you CAN do, which is to build your room such that the walls, ceiling, windows, doors, electrical system, and HVAC system are all isolated. You can still get good isolation for your studio like that, even without floating the floor.

Yep! Exactly.

Exactly! Spot on! You obviously already understand a lot of this stuff. So it's just a matter of figuring out how to put that into practice, to isolate your room.

Right. The audio range is generally considered to be 20 Hz to 20 kHz. There's actually not much going on at the extremes: the only two instruments that get down below 30 Hz, are the cathedral organ, and the concert grand piano: It's more realistic to think of the lower limit as maybe 28 Hz or so (a six-string bass gets down to about 31 Hz).

That said, even though small speakers don't have good specs for low frequency, they can still put out a lot of energy below their so-called "cut-off" frequency. A speaker where the spec says it goes down to 40 Hz, for example, could still put out a fair amount of power even at 20 Hz, which is only one octave lower.

Right! And if you do that, then your mixes sound terrible when you play them any other place outside the room!

Those two concepts don't go together, unfortunately. You can't have a really small room that is acoustically good for mixing. That's sort of like wanting a bottle of water that is dry, or a match that burns cold... :) In order to get the neutral sound that a control room must have (you are totally right about that: it must be neutral), then room has to be large enough for the acoustics to work. The specs for pro control rooms say that you need at least 215 square feet of floor space, to do that. Now, don't get too worried: you can actually get decent sound in a room that is smaller than 215 ft2: it's just easier to to it if the room is bigger. I have done rooms down to about 110 ft2 that turned out quiet successfully. But I would not go much smaller than that. The smaller it is, the harder it is to treat, and the less good the final result will be. Once again, it's all about the laws of physics... there are limits on what can be accomplished. So make our room as big as you can.

You are doing fine! :) You are asking the right questions in the right place, and you already have a good grasp of some of the concepts. It's just a matter of working through the right procedure now, step by step, and things will start to make a lot more sense.

- Stuart -

Easily the post of the century!

Stuart, I honestly cannot commend you enough for your insight, professionalism, encouragement and your willingness to share your knowledge. Your responses teach me so much, and I am truly and deeply grateful for it, and for you. Your wealth of knowledge is humbling, to say the least, and your outright willingness to share that knowledge is beyond admirable. Thank you so much, and thank you to all of you who keep this subforum alive.

Music is I'm my blood, and I have no option but to do it, and be absorbed by it. But music is one thing, and the quality of one's music is another. You guys have helps hundreds (maybe thousands over the long years) build better spaces, and contributed tremendously to helping people make better quality music, in their recording and mixing.

I can't thank you guys enough. And Stuart, I know you don't do this for praise or trophies, but you need to get a ribbon, or a medal, a pet poodle...a night out on the town...something.

Thank you again. May all of us here find prosperity, peace and happiness in our lives, musically and throughout.

Maniac 7777 19th October 2019 10:08 PM

Quote:

Originally Posted by gear_slut007 (Post 14269632)
Do you actually have this setup that you are talking about? Also, to be fair... he isn't out of place factually whatsoever and what he said is not that freaking crazy and can be approached quite simply from anyone willing to use a little brain power to approach it, like literally he covered alot but barely even broke the surface of the stuff for you to grant him such a title. Anyone can get it. I am not sure I am too familiar with the spring constant (although I assume he is talking to something to do with the tires being quite booyant and **** possibly producing ill effects and doing little to effect any sound) but resonant frequency is something to take very seriously. We do it all the time with out even noticing it. But basically what he is saying that light materials bad, heavy materials good. Porous materials not so good, dense materials probably better because the frequency at which they will resonate is lower. Everything in the world has a resonant frequency and when anything is exposed to it's resonant frequency it will experience certain phenomena mostly meaning it will start to produce excess vibrations itself thus defeating the properties of the noise cancellation for a given frequency band and harmonics and also exaggerating all sounds of a similar frequency in close proximity. An example of this is if your studio monitors resonant frequency is 33 hz (kinda low for a studio monitor to reproduce but more or less realistically feasible for a studio monitors resonant frequency) and that you are also making some music and decide to write a bass line using the C1 note (C1 note freq is 33hz and also that is for the most part an incredibly low note to being playing and not likely anyway), in theory the listener experiencing the sound would be exposed to a boosted representation of the bass line because the entire monitor itself would vibrate by nothing more than being exposed to it's resonant frequency and begin moving it's self (I say in theory because their are more variables at play here than just this stuff, IE amplifier and load etc). And so if you didn't know audible sound generally ranges from ~20hz ish i believe to some number around or above 20Khz (maybe higher say scientist) but also most studio monitors even in the 8 inch class struggle at producing bass frequencies at that level accurately so your bass is likely to be mute before it is to do this in a noticeable way unless you are applying an ungodly amount of EQ and as a result really driving your amps to push in the low end (probably slowly killing them)

Also I actually think this is a kinda sick idea for a jam room or something but I just need an incredibly small sound proof space for mixing and studio monitors that is as neutral as possible acoustically

Anyone please correct me if anything here is f'ed up beyond reconciliation I am doing my best...

I've seen floors suspended like this as a way to save money, not professionally but project artist studios. Brooklyn basement stuff. Stuart is the God of this field and if the Master Speaks, I being the fool on his journey, can only shut up and listen.

93 93/93

Soundman2020 21st October 2019 01:31 AM

Quote:

Originally Posted by VenVile (Post 14271863)
Easily the post of the century!

Stuart, I honestly cannot commend you enough for your insight, professionalism, encouragement and your willingness to share your knowledge. Your responses teach me so much, and I am truly and deeply grateful for it, and for you. Your wealth of knowledge is humbling, to say the least, and your outright willingness to share that knowledge is beyond admirable. Thank you so much, and thank you to all of you who keep this subforum alive.

Music is I'm my blood, and I have no option but to do it, and be absorbed by it. But music is one thing, and the quality of one's music is another. You guys have helps hundreds (maybe thousands over the long years) build better spaces, and contributed tremendously to helping people make better quality music, in their recording and mixing.

I can't thank you guys enough. And Stuart, I know you don't do this for praise or trophies, but you need to get a ribbon, or a medal, a pet poodle...a night out on the town...something.

Thank you again. May all of us here find prosperity, peace and happiness in our lives, musically and throughout.

Wow! Thank you so much for the kind, and somewhat humbling words. Much appreciated. Very much.

- Stuart -

gear_slut007 21st October 2019 02:21 AM

Quote:

Originally Posted by RyanC (Post 14270254)
This is really small and the dimensions are not favorable, a room this size will have poor acoustics. A lot posted in this thread already but it seems to be mostly about isolation. It's worth noting that with this small of a room and 5x5 footprint, no room for significant treatment, I think you would likely be better off with headphones.

I honestly kinda agree. But I'm planning on building it anyway because I honestly just prefer working on monitors. I realize the implications but I'm willing to risk it all at the hope I may find peace in this investment

gear_slut007 21st October 2019 02:34 AM

Quote:

Originally Posted by RyanC (Post 14270254)
This is really small and the dimensions are not favorable, a room this size will have poor acoustics. A lot posted in this thread already but it seems to be mostly about isolation. It's worth noting that with this small of a room and 5x5 footprint, no room for significant treatment, I think you would likely be better off with headphones.

To add to that...

I do not plan on much treatment. Just wall to wall carpet and hopefully enough sound proofing that I can shave ~40 db off any sound that escapes. According to the calculations provided by Stuart that may be just enough so my roommate/neighbors don't hear me mixing between 65-80 dbs (probably a little high yes but I have yet to do any actual room testing and not sure what my normal range is during mixing so I need to get a db meter still). I plan to add layers and layers of OSB followed by ply wood until I get the results I am looking for. I intend to build it 5x5x5 my hopes are that the cube shape combined with wall to wall carpet and carpet padding and strategic placement of my monitors will be just enough that the setup is usable for tracking. I have had a couple bad rooms I didn't like and it was because I was putting my speakers on the long wall then realized with some experimentation that the short wall is better and that symmetrical rooms can be bad for sound but I am willing to try. It is either this or headphones only... and that is not a acceptable outcome for me

gear_slut007 21st October 2019 03:03 AM

Quote:

Originally Posted by lynngraber (Post 14270294)
I am sure you've thought of this, but what about a nice pair of headphones? The idea you can't mix on headphones is BS.

I am kinda not sure how I really feel about this... what kinda headphones would you suggest? Right now I how some mixed emotions about this. If you asked me a week ago my answer would be more biased towards saying hell no to any headphones but even they it may sound insane I am actually starting to use a pair of Logitech G930 usb gaming headphones and kinda like them. I didn't necessarily mix I more or less just track while I am creating mostly electronic music and mix while I go so as to the usefulness for headphones for a solid mixing session from an engineers perspective I cannot say. However, typically in my case for tracking I fine headphones reprehensible. And I know this is kinda a crazy perspective from someone using gaming headphones to track but that's the thing with these headphones is that they actually work because they have built in DSP for simulating room effects and the lack there of is why I typically hate headphones, lol. I've tried to do headphones but I need to feel the speakers and that is the problem. I wouldn't say I can feel anything in these headphones but I wouldn't say I couldn't either because honestly I almost can. The bass response is good and the overall response is pretty accurate so far, lol

But seriously, outside my collection of cheap headphones and drummer isolation headphones (10 pairs all kinds of brands) I recently got a pair of Sennheiser HD 6XX and I hate the sound also despite the good reviews, I literally prefer my closed back drumming isolation headphones (Vic Firth or CAD) for tracking over these although I could see them being pretty dope for vocal sessions so far. I have about 8 hours in them so I know I am still a ways from burning them in but yea, what are your suggestions for a set of headphones? I have been told I could need a tube amp to get the best out of the HD 6XX so I'm looking for one but mostly been held up because I really want something rack mountable but almost all of them seem to be desktop because the tubes which I don't really like

I am also looking for a pair of planar headphones as I heard they tend to produce better stereo images or at least tend to have a wider more natural image. In general I just don't love headphones but this pair of Logitech G930 gaming headphones are literally the only competition right now and I'm starting to like them but either way I am only looking into headphones as an alternate option. I am definitely trying to build this room. I seriously can't live on just headphones

Starlight 21st October 2019 11:21 AM

Quote:

Originally Posted by gear_slut007 (Post 14276464)
I intend to build it 5x5x5 my hopes are that the cube shape combined with wall to wall carpet and carpet padding and strategic placement of my monitors will be just enough that the setup is usable for tracking.

5 feet x 5 feet x 5 feet. Are you really wanting to build an impossible challenge for yourself? And only 5 feet high? What plans do you have to treat the modal activity between 112Hz (0-0-1, 0-1-0 and 0-0-1 modes) and 823Hz (the Schroeder frequency)? Carpet and carpet padding will only treat the highest of frequencies, somwhere upwards of 8kHz so they cannot be your plan.

I don't want to dampen your enthusiam but dude, you need to take a reality check before you waste your time and money doing something stupid.

b0se 21st October 2019 11:51 AM

Indeed, 5x5 would have terrible acoustics. Headphones would be a better (relative) option. The notion you can't mix on them is unfounded.

1) You don't need a tube amp, that's only recommended for audiophile playback. For mixing, avoid at all costs as it colours the sound. You want a clean headphone amp that will easily power the cans. The new Rupert Neve headphone amp is only $400 and will work wonders for that.

2) EQ your headphones. I have Focal Clears and the difference is astounding. I use CraveEQ based on the curve measured and suggested from this list. I tested many EQs for this (Equilibrium, Fab Flter etc) and Crave sounded the most transparent and effortless.

https://cravedsp.com/

Avoid Sonarworks. I own it, and it sounds awful compared to Crave + EQ curve from the above list. Another option—which I have not used personally but have heard good things about—is Tonebooster's Morphit .

3) Lastly, and this is incredibly important, follow up the EQ plugin with Goodhertz CanOpener. It simulates speaker crossfeed in your headphones making the experience far more natural. Crucial for mixing.

If you're an OSX user, the rather marvellous app AudioHijack is all you need to place the EQ and CanOpener between your sound source (app, DAW or entire system) and your audio interface.

@ Soundman2020 - hats off for offering such insight, and @ VenVile - a lovely post indeed!

lynngraber 21st October 2019 06:04 PM

HD600 powered by a Grace m900 with Sonarworks correction is a good start. If the headphones sound "bad", they may actually be telling you what you need to hear. Most consumer cans are hyped in the lows and highs to make whatever goes through them sound good.

The HD600 are not, but they require a good amp to drive them at 300ohms

gear_slut007 26th October 2019 01:46 AM

Quote:

Originally Posted by Starlight (Post 14276891)
5 feet x 5 feet x 5 feet. Are you really wanting to build an impossible challenge for yourself? And only 5 feet high? What plans do you have to treat the modal activity between 112Hz (0-0-1, 0-1-0 and 0-0-1 modes) and 823Hz (the Schroeder frequency)? Carpet and carpet padding will only treat the highest of frequencies, somwhere upwards of 8kHz so they cannot be your plan.

I don't want to dampen your enthusiam but dude, you need to take a reality check before you waste your time and money doing something stupid.

Yea, idk. I am over the top all the time. Perhaps I need to take it down a notch but I've concluded my honest goal in this project would be to reduce my noise by 40 db so as to not piss off anyone that should be good enough according to the math provided by stuart but you make some fair points most of which I am not all to familiar with