New to me studio! Stripped of its acoustics :(

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unnus
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New to me studio! Stripped of its acoustics :(

Post by unnus »

Hey all! I've been lurking for a long while because I was initially planning on buying a home and doing a build from scratch. Well, the opportunity fell in my lap to buy a home in the neighborhood I was interested in, that was, coincidentally, owned by a local recording studio owner and engineer. Turns out, he used to operate said studio out of his basement prior to moving into a full commercial building, and he left the studio pretty intact, minus stripping all acoustic treatment. What an opportunity!

I'm looking to get an idea of where to start with acoustic treatment and get some insight on if I've got the right mindset starting out, it'd be much appreciated!

It's a 3 room design, consisting of a control room (hard floor, soft ceiling design), vocal room, and a live room. The live room utilizes the "room within a room" design, and I have confirmed with the previous owner this was all done properly and to code. All rooms have isolated grounds, 20amp outlet runs on separate breakers, the whole 9 yards. Saves me a ton of headache. The walls are covered in 2x2 and 2x4 acoustic ceiling tile, the live room has the same material on the ceiling (not a drop ceiling) as well. The live room and vocal booth floors are laminate flooring, while the control room is bare concrete with sealer on it. I think it's got good bones, just needs a little love.

Essentially, I'm thinking we need to gut the tiles out and redo them, as they have chips from the contact glue used on the old pyramid foam used, and chips/dents/missing bits. I'm most likely going to use the same type of tile again, as it runs about 55 cents a square foot at Lowes. On top of that, I'm thinking broadband panels and foam along the walls, and then build floor to ceiling traps for every corner. Maybe for the corner where the door is for the control room, I'm also thinking of doing a ceiling curtain rail and hanging a very thick acoustic blanket for that corner to allow walking in and out of the room?

Apologies in advance, I tried reading through as much as I can, and I do need to invest in a measurement microphone to get a baseline as well I think, so I can get tuning the right way. This is my first house (and a surprising achievement for myself at 21 years of age), and first 'bigger' studio, as well as my first live room I plan on tracking in, and I want to do it all correctly. I've included images and a floor plan I've created with the measurements I took this evening.

Thank you guys and gals in advance for any of your wonderful insight!

Control Room
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Live Room
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Vocal Booth
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Gregwor
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Re: New to me studio! Stripped of its acoustics :(

Post by Gregwor »

Congratulations on buying the home!
Essentially, I'm thinking we need to gut the tiles out and redo them, as they have chips from the contact glue used on the old pyramid foam used, and chips/dents/missing bits. I'm most likely going to use the same type of tile again, as it runs about 55 cents a square foot at Lowes.
I would yank all of the ceiling tile and ditch the idea of using ceiling tile all together. I'd toy with the idea of hanging some poly diffusers and broadband absorption on the ceiling instead. For the walls, treat them accordingly. Those ceiling tiles are far from your best option for treatment.
Maybe for the corner where the door is for the control room, I'm also thinking of doing a ceiling curtain rail and hanging a very thick acoustic blanket for that corner to allow walking in and out of the room?
Home studio builds are plagued by existing basement layouts so I'm sure the guy did the best he could laying out the studio but for the control room, I can't think of a great solution to lay things out as there is lack of symmetry and it's already below the recommended floor size.

Lastly, for any future pictures you post, can you please make them larger (max 1200px wide or tall) so that we can see them better? Thank you!

Greg
It appears that you've made the mistake most people do. You started building without consulting this forum.
DanDan
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Re: New to me studio! Stripped of its acoustics :(

Post by DanDan »

Congratulations. You may become a Mogul! If areas of tile are clean I would be inclined to just leave them there. Install treatment as normal just ignoring them.
Any place they are exposed they will still kill HF reflections, flutter echo.
How about using the 'Live Room' as the CR?
DD
Soundman2020
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Re: New to me studio! Stripped of its acoustics :(

Post by Soundman2020 »

Hi there "unnus", and welcome to the forum!

What a great find! Pretty unusual to find a house that already has a studio in it, in reasonable shape. There's a lot going for that place, but also a few things going against it

The first thing against it, is the low ceilings. Since this is a basement, that sort of goes with the territory: most basement studios start out with low headroom, and end up with even less. But there are often ways of improving on that. As Greg mentioned, "acoustic" ceiling tiles are not the best solution... It would be worthwhile taking some of those off, to see what's going on above. You might find a pleasant surprise up there, such as more space above you that could be put to good use acoustically. Or you might find nothing useful. But either way, there are better solutions that acoustic tiles, which aren't even being used correctly, and have little benefit for a studio ceiling in any case, even when they are being used correctly.

The vocal booth looks reasonably good (except for the low ceiling): Big enough to be usable, with suitable treatment, of course. Probably the usual plan for vocal booths would work OK there. It's still small, so it will have that classic "boxy" sound to it, but that can be minimized to a certain extent with the treatment.

The live room is a nice size, at nearly 250 ft2... Once again, you have that low ceiling: very low here, at just 7'2": presumably due the lost height is due to the isolation. I'd hazard a guess here and say that the isolation ceiling was built conventionally, not inside-out: If you want to go to the trouble of re-doing that as a true inside-out ceiling, you could gain back several inches of acoustic height in the room: however deep the ceiling joists are. In other words, if the ceiling joists are 2x8s, then you could potentially gain back over 7" of acoustic height in that room, and if they are 2x10s then you could potentially gain over 9" of extra height: that is very much worthwhile, for sure, if you need the best possible acoustic response in the live room. On the other hand, if this is more of a hobby studio for your own pleasure, rather than a place where you'll be recording professionally, then that's probably not worth doing that.

The problem, as Greg pointed out, is your control room: as he already mentioned, there's no way I can see of laying that out symmetrically. Symmetry is critical for a control room if you want your mixes to translate well, and sound well balanced. That's going to be a major challenge to make that room usable as a control room. I fear there may be some major surgery in store for you with that room. Without seeing the rest of the layout (a proper floor plan, showing all the rooms / walls / limitations around it, I can't even guess at what could be done to get it working. It's on the small side already: the figure of 215 ft2 floor area is often quoted as being the minimum necessary for a critical listening room. That said, I've designed a few rooms smaller than that, successfully, so it should be possible to do somthing with it. I'm suspecting that maybe a "corner control room" layout might work for it... with caveats!
The walls are covered in 2x2 and 2x4 acoustic ceiling tile,
I just noticed this.... Hmmmm... So it's the WALLS that are covered with the tiles, not just the ceiling? Definitely dump those! As I mentioned above, "acoustic" ceiling tiles don't really have much on the way of "acoustic" properties that are useful or studios, and even the little bit of good they could do depends on the being installed correctly, as they were designed to be installed: with a 16" air plenum behind them! (Or at least SOME air, even if it's only 12"). The acoustic properties of those tiles only work when they are used as designed: gluing them to the walls is not the way they were designed to be used. Many people make this mistake: they see the word "acoustic" in the product advertising, and think that it means they have great acoustic properties for any and all situations: they don't. As with all products, of any kind, then only work as designed when they are used as designed: and acoustic ceiling tiles were designed to be used in the drop ceilings of offices, shops, schools and other such spaces, along with the acoustically important air gap behind them. When used like that, they do indeed provide god acoustic properties.... as needed for offices, shops, schools, etc... but NOT as needed for recording studios! Studios ave very, very different acoustic needs, as compared to those.

Below are two images of actual test results from testing of ceiling tiles in acoustic test laboratories. The first is a table showing the results from testing the acoustic absorption if ceiling tiles when mounted correctly, using the "E400" method of ASTM C423, which basically means that they were mounted with a 400mm air gap behind (about 16"). Look at the "absorption coefficient" column: As you can see, this tile has reasonable absorption above about 500 Hz, and not-so-reasonable-but-still-partially-usable below that. Studio designers usually consider absorption coefficients of over 0.5 to be interesting, and over 0.8 to be very interesting. (0.5 implies absorption of about 3 dB. Anything less than that isn't a lot of use.)
acoustic-ceiling-tile-test-report.jpg
That's for the "E400" mounting, with a large air gap. The graph below of for various types of ceiling tile with "A" mounting, which means no air gap: The tile is directly against the wall or ceiling surface:
acoustic-ceiling-tile-against-wall-coefficient-graph.jpg
Look at the lower line on that graph: the solid line, for the "no holes" type of ceiling tile. As you can see, the coefficient for that is well below 0.1, and actually around 0.05, for most of the range. Not very impressive at all! An basically no use, acoustically. That's way less than 1dB absorption. In fact, of you look at that graph, even the specialty acoustically designed high performance tiles with holes and fissures, have pretty lousy performance when "A" mounted. There's just a small section where things get vaguely interesting, around 2 kHz. But for the low end? Nothing at all. Zilch. Nada.

So, to cut a long, boring story short, those tiles on the walls are what are causing your rooms to have that somewhat dull, rather lifeless, but "boomy" or "muddy" sound to them. They are not doing what the rooms need, acoustically. And in fact, they are doing the opposite! Small rooms need major low frequency absorption, some controlled mid-range absorption, and little to no absorption in the highs. Your tiles do the opposite. Somewhat like carpeting, they do the total opposite of what the rooms need, acoustically.
The live room and vocal booth floors are laminate flooring, while the control room is bare concrete with sealer on it.
:thu: Excellent! In both cases! That's a really good start.
Essentially, I'm thinking we need to gut the tiles out and redo them,
Gut them, yes, absolutely, but don't redo them! Instead, design the treatment that each room actually needs, and put that in, instead. Determining what that is, requires some testing and carefully working through a bit of basic acoustics, but isn't that hard to do.
On top of that, I'm thinking broadband panels and foam along the walls,
Perhaps, but only as needed. But forget foam: The typical then "acoustic foam" that you often see advertised, with the wavy surface, or wedges, is pretty much the same as acoustic tiles... :) (OK, maybe that's a bit harsh: it's slightly better, but not by much). Rather than just throwing up stuff at random, you should first plan what you want each room to sound like, then do some acoustic testing to see how it is behaving right now, then design the treatment that is needed to take it from "how it is behaving right now", to "what you want it to sound like".
I'm also thinking of doing a ceiling curtain rail and hanging a very thick acoustic blanket for that corner to allow walking in and out of the room?
Bad idea.... acoustic blankets are for industrial applications, not studios. Firstly, the look pretty ugly, and second, then sound even worse... :)
and I do need to invest in a measurement microphone to get a baseline as well I think,
Right! I'm not sure if you have seen this, but it should put you in the right track: How to calibrate and use REW to test and tune your room acoustics
Apologies in advance, I tried reading through as much as I can,
Great! In addition to the forum itself (there's no better place on the planet, actually.... :) ), you should probably also read "Master Handbook of Acoustics" by F. Alton Everest (that's sort of the Bible for acoustics). That will give you the basics for understanding acoustics, so you can get a handle on what's wrong with your rooms, and what treatment you'll need to design to get them where they need to be.

For the control room, there's a document with the cryptic title "ITU BS.1116-3" which you can google then download. It defines the acoustic response that a "critical listening room" needs. A control room is exactly that: a critical listening room. So the acoustic response they define in that document is what you should be aiming for with your control room. The specifications are very clear, very well defined. You only need to look at chapters 7 and 8 in that document, as the rest is not applicable to control rooms, but those two chapters are. But to summarize; the acoustic response of a control room must be absolutely neutral. The room must not add anything to the sound coming out of the speakers, and must not take anything away. It most not "color" the sound in any way. That refers to frequency response, phase response, and also time domain response. In fact, the time-domain response is the most important part of the room acoustics. Most people assume that they should be aiming to get the frequency response flat, and that's a nice goal to have (although achievable in small rooms), but a far better goal is to have flat time-domain response: in other words, all frequencies decay at the same rate across the entire spectrum, with no frequency "ringing out" longer (or shorter) than any other, and with the overall decay time being the correct one for that size room. If you can get flat time domain response, then your frequency response will be pretty darn close to flat as well, and then you could use digital tuning for the final tweaks.

So that's the way I see your studio right now: Good possibilities, a decent sized live room, reasonable vocal booth, but problematic control room shape, and low ceilings, with the currently remaining treatment needing to be taken out and replaced with stuff that actually does what the rooms need.

- Stuart -
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