Mix room design/implementation help...

[rogersmasson]

Hi everyone,

My apologies to those who viewed my first post, and thanks to Stuart who clued me in to the correct procedures and practices on this forum. It's my first time reaching out on a forum, so I was a bit green. Onward...

My name is Rogers Masson and I am a producer/mixer and live in Nashville, Tenn, USA. My work covers different genres and has taken me all over, but I typically bring tracks back to my studio here in Nashville for mixing. I also spend a good deal of time mixing projects that are sent in to me...thank goodness for Skype and Gobbler! My mix results have been successful to a degree- clients are happy, labels are happy, songs have done well on radio in different markets, and have sold fairly well. But there are plenty of problems with my room that I can hear, which I work around and usually have to tweak in mastering, and would like to improve the room for easier/better/more honest mixes. Don't quite know how to fix the issues with the room.

Side note... This is a rented flat, and it's a live/work space. The landlord allows me to do just about anything I want, as long as I'm not tearing out walls. I can drill, cut in to walls, remove doors, install cabinets, etc. I would like to implement acoustic elements that help level out the room, but are not permanent installations. Not even sure if this is possible, but I'm willing to try just about anything. My budget is not necessarily strict, I want to do this right, but of course do not want to throw money away on things that are not going to work. Would love to do this for $500US, but I expect it's going to cost quite a bit more. Not trying to be vague, but again the right fixes will trump the costs involved.

I love to build, do a lot of woodwork and home repair in my off time. I don't want to glue foam to the wall and blindly convince myself that it's "fixed" because a brochure says it's the best thing to put in your studio since Neve. I'm looking for design ideas, advice, and the like. Thanks in advance to anyone willing to lend me some of their time and thoughts.

I've measured, taken pictures, went to the RT60 page, shot the room with some free Mac software and a mic, and even spent some horrifically embarrassing time with SketchUp...I felt like a baby deer trying to walk for the first time, it was not pretty. I'll attach everything I have- dimensions, pics, estimated RT's, results from shooting the room, primitive line drawing looking down on the space, etc. If there are any questions, or any additional information needed, just let me know and I will get answers to you straight away. I'll keep things in feet and inches, unless you would like me to post metric figures. Here are some of the stats requested in the "Before you post" page...(pictures to follow)

>I typically mix in the 70dB - 80dB range (C weighted, slow response), occasionally gaining the level to get a feel for the air moving in the low end.

>My neighbors are not an issues as my flat is located in a two story building surrounded by other businesses. It is above a mobile phone store, but my mix room is above their storage area. They are super cool, and close by 6pm every day. It's an older(by US standards anyway) building that is zoned for both residential, and business occupation. Really a fantastic location, and situation since I don't have to rent a separate studio space to run a legal business out of.

>The structure is brick and the walls are very thick (1' 6"). The floors are wood, they sag and are not level due to age. The walls are plaster over lath wood. 8" decorative crown molding where the walls meet the ceiling. The ceilings are 12' high throughout the flat.

>There is a drop ceiling in the mix room. I think that's what they are called. It is a metal frame with a bunch of acoustic tiles in the frame. This false ceiling is 2' below the actual ceiling, and covers the entire room.

>My studio is in the back of the flat, there are two separate HVAC systems, one for the front space, one for the back space.

>There is an entrance door, solid core, to the studio from a hallway. There is a very large window (98" H x 40" W) directly across from the entrance door. And a door leading out to the back deck area. This door is located on the back wall and is mainly glass framed by wood.

>There is an alcove created by two closets on either side, with solid core doors on them. This is my mix position for now, and my front wall. When in the mix position the entrance door is to my left, the window is to my right, and the door to the deck is to my back. There is a closet to my immediate left, and another of the exact same size to my immediate right which are 7’ 8” apart from each other, and they are both 3’ 7” deep. The closet walls go all the way to the ceiling, but there is a wall that is between them that comes down from the ceiling and stops at the 7' level(measured from the floor to the bottom of the wall). Very strange, perhaps it was a built in kitchen at one point.

>There are electrical outlets on each wall. except the back wall. There is an overhead wire for a light, but I've not installed one at this point.

>Right now I just have a few pieces of wrapped 703 directly on the wall, along with a bunch of other framed stuff, instruments, etc. There are also two 6’ H x 3’ W book cases along the left and right walls that are both set in the far back corners and touch the back wall.

>I mix on a homemade desk, in the box, using Dynaudio speakers and a 32” flatscreen tv as my monitor.

>There is one rug on the floor (5’W x 8’L), and a cloth covered desk chair. There is a leather couch located in the center against the back wall. There is one small coffee table in front of the couch.

Here is the best I could do with a line drawing program. The window at the bottom of the pic is actually directly across from the door at the top of the pic. They are both 6" away from the closets on the front wall. The entrance door is 36" wide. The front wall/mix position faces North...

RoomLayout.jpg

===
Here are some pics...

The front wall/mix position left...

Front Wall Lt.jpg

The Front wall/mix position right...

Front Wall Rt.jpg

Center front wall/mix position and the weird alcove...

Center Front Wall.jpg

Back wall right (over my right shoulder when mixing)...

Back Wall Rt.jpg

Back wall left (over my left shoulder when mixing)...

Back Wall Lt.jpg

Drop ceiling...

Drop Celiling.jpg

Inside drop ceiling...

Inside Ceiling.jpg

===
Here are some numbers and graphs...
Estimated RT60

125Hz - 0.45

250Hz - 0.98

500Hz- 0.68

1kHz- 0.6

2kHz- 0.53

4kHz- 0.56

Actual RT

RevTime_Actual.png

===

Ok, that about does it for now. Again, thank you all for your insight and advice, it is greatly appreciated.

Best,

Rogers

[Sullli]

No problem dear Rogers. BTW: Seems like your design is pretty good.

[Soundman2020]

Hi Roger, and Welcome!

Great first post!!! Nice to see someone who takes the time and effort to get it right, and include all of the info!

Some comments:

>My neighbors are not an issues as my flat is located in a two story building surrounded by other businesses.

OK, so sound going out is not a problem, but what about sound coming in? Are you close to a road / freeway / hospital / industrial area / train station / airport? Do you get rain / wind / thunder / etc in your area? Any people, dogs, cats, radios., TVs, cell phones, or parking lots close by? What about inside the building? Are there any bathrooms, kitchens, elevators, water tanks, HVAC, motors, etc.? All of those and many more might make noise that you need to keep OUT of your room. You might want to get an SPL meter, and check what issues you could have, before deciding on your isolation strategy.

The structure is brick and the walls are very thick (1' 6").

Cool! That's GOOD news! Plenty of mass in there.

The floors are wood, they sag and are not level

That's NOT good news. Not at all. I'm looking in my trusty crystal ball, and I'm seeing some major floor work in your near future...

The walls are plaster over lath wood.

Also not so good. Can you take them down if need be?

The ceilings are 12' high throughout the flat.

Nice! Lucky you! You should be able to get some nice acoustics in that kind of space.

>There is a drop ceiling in the mix room. I think that's what they are called. It is a metal frame with a bunch of acoustic tiles in the frame.

Most likely that isn't doing you any good at all. Those "acoustic" ceilings are designed for office-type noise, not studios. Not a lot of use to you, as is.

>There is an alcove created by two closets on either side, with solid core doors on them.

What is inside the closets? Any chance you can gut them? You could use them for soffit mounting your monitors, or maybe for bass trapping.

Looking at your graphs, your overall RT-60 seems reasonable, but clearly you have an issue with the wildly varying levels for different frequencies. Ideally, you want that curve as flat as possible. You obviously have a bunch of issues below 400 Hz, so you should probably start with abundant deep broadband bass trapping in all the corners that you can get to (there are twelve in a rectangular room).

Also, that graph is not in fine enough detail: it is on 1/3 octave by the looks of it, so there could be even more serious issues hiding in there that you can't see. Is your software capable of generating far more detailed graphs? Waterfall plots would be even nicer!.


- Stuart -

[rogersmasson]

Hey Stuart,

Thank you so much for the kind words, taking the time to read my post, and for sending over some solid comments/quests. I’ll try to answer as best I can, in the order you asked. I don’t quite know how to do the cool “quote” thing you did, or if I’m even posting this reply correctly, but I’ll do my best...

Sound going out is not a problem at all, and in many ways sound coming in isn’t really either. There is a street that runs along the window side(East) of my building, and depending on the time of day it can be fairly busy, mainly in the mornings. At night, not much traffic at all. The speed limit is very slow though, and it doesn’t really bother me, or hasn’t anyway. No parking structures, not much city noise actually. The building is not connected to any other structure. We get all kinds of weather here in Tenn, across the spectrum really. Thunderstorms, wind, snow, heat, etc. Inside the building, across the hallway from the entrance door to my mix room is a bathroom. But I’m the only one that uses it. All of the plumbing for the unit below me is in the far corner of my flat, so I never hear it at all. Air conditioner units are located on the roof, again in the far corner of the building away from my mix room. The average dB level, just the ambient noise in the room is approx. 45dB at this point(C weighted, slow response). I’ve basically zoned out any noise from the street while I’ve mixed. A car goes by, I ignore it and stay focused on my mix. Since I know what it is, I know how to set it aside while I’m working. Not sure if that makes sense, I guess I’ve just made the best of my situation and carried on. I would like it to be quieter, more focused, but don’t think it would bother me much if the room was not completely isolated from outside noise. I think the frequency response of the room, the honesty of it, is more of a priority at this point.

Agreed on the ceiling, but was hopeful I might be able to put it to use and not take it out. Oh well.

The closets are basically empty at this point, bare with no shelves. I keep some guitar cases in one, and some wood working tools in the other. I figured they would be great for bass trapping, but don’t know how to best approach that. Just fill them with massive amounts of insulation?

Glad to hear my RT-60 seems reasonable. Thought the low frequencies were way out of whack, but I expected that considering I have not bass trapping at this point. I noticed a major dip at 1kHz, in every test I do. Could that mean a node that is canceling out that frequency? Or perhaps the ceiling tiles?

I’ll get a better graph together and post that asap. The program I used was just a free mac thing called FuzzMeasure and that’s the best it offered. It does do waterfall, but again I think it might just be a cheap quick picture. Let me research this and get back to you.

Again, thank you so much for your insight and advice.

[rogersmasson]

Oops, sorry Stuart, forgot to give you the ambient noise level in the mix room...

average is between 36dB and 38dB

[Soundman2020]

I don’t quite know how to do the cool “quote” thing you did, or if I’m even posting this reply correctly, but I’ll do my best...

You're doing fine! The quote thing is easy: just copy and past the text you want to quote, highlight it with the mouse, and click on the "Quote" button just above the area where you type your answer. Bingo! Or you can type the word "quote" between square brackets "[ ]" just before the text you want to appear as quoted, and then type "/quote" between square brackets at the end. It will look like this on screen, but without the spaces: [ quote ] This is where you put the test you want to quote. [ / quote ], but when you send it, it comes up as quoted text.

OK, so based on what you say, isolation is not your major goal right now, and treatment is. You want the room to have fairly flat response and consistent RT60 times. Sounds like a good goal!

I figured they would be great for bass trapping, but don’t know how to best approach that. Just fill them with massive amounts of insulation?

Yup! That will work fairly well. The other thing you could do is to do that for the bottom third and top third of each closet, then use the center section to soffit-mount your speakers, which has major worthwhile benefits: tightens your bass, eliminates mid-range comb filtering and reflections from the front wall, gives you a great stereo image, etc. Basically, you just install your speakers inside the closet space and put a new, much bigger front panel around each one, made of heavy wood or some other dense material with a hole cut in the middle of the exact shape and size so that your speaker can just fit in with its front panel poking through to be flush with the soffit panel. It's a bit more complex than that, and we can go into all the details if you decide to go that road (which is highly recommended), but that gives you the basic idea: your speakers would appear to be built into the front wall of your room. You also have enough room height that your speakers will not be centered on the vertical axis, which is great, and there will be plenty of room above the soffits for bass trapping.

I noticed a major dip at 1kHz, in every test I do.

I saw that too, but I'm guessing it is a deficiency in the test setup itself: maybe the crossovers in your speakers, or the response curve of your mic / preamp / interface, or something like that. What mic and speakers did you use for the testing?

Could that mean a node that is canceling out that frequency? Or perhaps the ceiling tiles?

I don't think so, since it is so high up in the spectrum. I wouldn't expect to see modal issues at 1.2 kHz: your modes should be very close and even at that point. Modal issues are normally below about 300 Hz, rarely above. That's why I'm suspecting speaker/mic/interface. I'd eliminate those first. If you can provide the specs (make/model) of your speakers and text mic, I can try to figure out if they might be responsible. Or you could just try with totally different speakers and mic, and see if the 1.2 kHz issue goes away.

I’ll get a better graph together and post that asap. The program I used was just a free mac thing called FuzzMeasure and that’s the best it offered. It does do waterfall, but again I think it might just be a cheap quick picture. Let me research this and get back to you.

If you have access to a PC, instead of a Mac, then you can get REW (stand for Room Eq Wizard), and its pretty good. It's also free: you can download it from Home Theater Shack (you have to register first, I think, but that's also free).

- Stuart -

[rogersmasson]

Ok, next reply I’ll give the “quotes” a go...

Yes, would love a room with a fairly flat response and consistent RT60 times! I know it’s going to be a challenge, and hope it can be done.

Front wall-
Do you think it would work to fill the closets with 703 and build a front wall that essentially sits inside of the alcove? I’ll include some more pics focused on the alcove so you have a better feel for the space. The dimensions on the line drawing from my first post are correct. Not sure if that would give me enough width between the speakers(?). And would that change my 38% mix position? I suppose it would, but not a concern for me.

I love soffit mounted speakers by the way. My favorite rooms, everywhere I’ve worked, have always had soffit mounted speakers. Love the focus, the bass, the everything!

Front1.JPG

FrontTop.JPG

FrontInside1.JPG

FrontInside2.JPG

1kHz dippy doo-
I’m using Dynaudio MI-5’s, not soffit mounted, and an analysis device I borrowed today from the mastering facility I use is called an IVIE model IE-30A, which has an omni fancy mic attached to it that looks quite a lot like an Earthworks mic. I’ll attach a couple pics of it, and it’s freq view of my room. The 1kHz dip is gone, I suspect due to the more accurate analysis equipment, but now I see a serious dip at 50Hz. Yikes! You were right about potential problems lurking about below 400kHz.

LowFreqs.JPG

MidFreqs.JPG

HiFreqs.JPG

PC-
I’ll borrow one from a buddy and load on that software. Thanks for the lead on that, really appreciate it.

Drop ceiling-
Do you think if I hung a bunch of free swinging and randomly placed 4” 703 (2” on either side of fiberboard or pegboard) in the open area between the ceiling tiles and the ceiling, that it would allow me to keep the ceiling tiles up? Just trying to avoid ripping all that crap out, call me lazy! In other words, is there a way to actually use the drop ceiling to my advantage? Perhaps taking out random tiles, and replacing them with fabric frames that allow more sound waves to travel up and in to be soaked up by the hanging baffles?

My building-
I'll include some pics of the building itself so you have a better picture of what I'm dealing with.

Best,

Rogers

Looking from my deck in to the mix room...

BackDoorToStudio.JPG

Looking up from the parking lot behind my building. I've got the entire top floor of the building, with my studio in the back section you see here...

Back.JPG

This is the street side looking up at my place. The studio is where the last window is located to the left of the picture...

Side.JPG

And this is the other side of the building, look down towards the back parking lot...

OtherSide.JPG

[rogersmasson]

Forgot to add this info...

Regarding the frequency response picture of the room, I shot the room with white noise, at 60dB.

[rogersmasson]

Ok, I know this was really easy for the rest of you, but I had the hardest time figuring out SketchUp. Had a major breakthrough today though! Of course, this has left me a day behind on my mixes...but I know how to draw on the computer!

One thing I can't figure out for the life of me is how to reduce the .skp file size so I can post it on here. I'm sure it's been covered but I am having trouble located just how to go from a 1.5mb file down to a 700k file. Or how to link the file so anyone who wishes to view it can download it. Help would be greatly appreciated.

So here is a jpg of my room finally, in it's SketchUp form, thanks for any help and suggestions you may have.

Best,

Rogers

The RogMahal2.jpg

[Soundman2020]

Ok, I know this was really easy for the rest of you,

Riiight! We all learned it in ten minutes! Not!!!! Yeah, it takes a little while to get your head around the basics, but once you do, it all makes sense, and it's a really powerful tool... as you just discovered! Glad you mastered it!

One thing I can't figure out for the life of me is how to reduce the .skp file size so I can post it on here. I'm sure it's been covered but I am having trouble located just how to go from a 1.5mb file down to a 700k file.

Window -> Model Info -> Statistics -> Purge Unused. That will get rid of anything in the file that doesn't belong any more. One of the quirks of SketchUp is that when you delete something, it doesn't actually get deleted from the file yet! You have to purge it to finally get rid of it. Also, beware of downloading models form the internet: they can eat up space in your file like you wouldn't believe! I once thought it would be cool to put a detailed drum kit in one model of a live room, and it suddenly jumped to about 14 MB, then was really hard to move around on-screen!

Just a word to the wise....

- Stuart -

[rogersmasson]

Rock!

Stuart, thanks so much for the info. After some strategic purging, I'm within the upload size margins. Here is my room in SketchUp land...

The RogMahal_P.skp

Any design help/ideas would be greatly appreciated.

Best,

Rogers

[Soundman2020]

Hmmmmm.... you say your landlord will let you do a lot of things, so here's a curve ball: Is there any chance at all that he'll let you remove those closets completely? Meaning: take of the doors, and also take down the partitions that separate them from the alcove? It would be great if you could do that (maybe promising to rebuild them if you ever leave, or to replace them with something similar). It would give you the space you need to do the front of your room properly. You would then have the whole front of the room, open, wall to wall, except for the strange wall above the center, but you could make really good use of all that extra space.


- Stuart -

[rogersmasson]

Not much of a curve ball, I believe that I could do that. That is such a funky alcove/wall/thing. I think it was an add on as it's drywall and not plaster. That would add 3'7" to the length of the room, and 6'6" to the width by taking out the closets, and the wall above the center section.

I was trying to do something somewhat modular, and possibly removable/moveable since the building is not mine. Also, and probably more importantly, I've got tons of producing/mixing work going and that type of de-construction tends to take a great deal of time to re-construct.

With that said I'm open to option and ideas. Is there any way to use the closets and all the space between the closets as bass trapping? Or is it just too massive in the overall room to be of any use acoustically? Also, if I built a modular type of front wall that fit in to the space between the speakers, would my speakers be too close together for a good stereo image?

Thanks again for the info.

Best,

Rogers

[gullfo]

you should take out the closets and alcove and make it into a proper soffit and trapping. also consider a false ceiling since you have the height and use that space for a lot more trapping. out of your budget but an inner isolation wall would be best and since you're using angled treatments and such, the landlord shouldn't see it as an issue and you could take the treatments with you. consider soffit components for the front of the room so they can be moved easily. the false ceiling is really a layer of rigid insulation and cloth on a frame. this could also be modular. if not, clouds - just absorptive should do it.

[rogersmasson]

Hey Glenn,

Thanks so much for the info. I've seen quite a few of your posts, and they all have such valuable information.

Looks like that's what I'm going to have to do, go ahead and remove the closets/etc.

Would you happen to have a SketchUp version of the jpg you attached? Just so I can check out the angles and such. Thank you again for your help and consideration.

Best,

Rogers