Room Testing Software for OS X

[los marbles]

I have currently relocated to a small untreated room in my house. Long story. Anyway, I have serious issues in my little space (low frequency cancellation it seems) I need to purchase room testing software that will run on Mac OS X 10.3.9.

Can anyone direct me to this?

I need to get a handle of what's happening in here so I can get to work building/buying some traps and diffusers.

My room is very small: (L) 10'7.5" x (W) 9'1.25" x (H) 8'1"

Any help is greatly appreciated.

John

[Ethan Winer]

FuzzMeasure

[los marbles]

Thanks Ethan, however, it appears that software runs on a later OS than mine. I use an older PT mix core system which is why I run an older OS. I have a PC laptop that I use for admin stuff but I have no recording software on it.

I dunno, I'm very "green" at acoustical treatment but I have been researching this forum and other sources extensively lately. I have also read your page re: Acoustical Treatment and that has shed much light on the situation.

I do not have a big budget for this, most (all) of the money I make recording goes to a mortgage, wife, kids, auto upkeep, etc...however, treating my room needs to be done. My older system works and sounds very good and although I will upgrade this year, the acoustical treatment is priority number one. No upgrades or gear will make my work any better until I do.

I just moved my studio into my own home and previously worked in a treated environment so it was never an issue until now.

As I said in my OP, I have a bass null happening. From what I have researched so far, it seems I need to build broadband traps for all corners, back wall, behind speakers, and ceiling and sidewalls using the mirror method.

I wanted to test the room to get a clue about higher frequencies, as well as find my low end dip, and I am unclear about what I should do about diffusion (basically handling higher frequencies). Placement of diffusors and ratio between bass traps, other absorbers, diffusion is what I am looking for.

If you or anyone has any suggestions for a room my size (or experience with similar dimensions) I am all ears.

Thanks VERY much.

[DanDan]

Hi John. I would not worry about Analysis. It is expensive and takes years....:-)
The Acoustic info at RealTraps, GIK and elsewhere is concise and accurate.
You really don't need any more info than is sitting there.

Bass Trap as many corners as you can, with the biggest Bass Traps practical. There is no maximum amount. Most is best. I have had great success with SuperChunks.

Do the RFZ process with the mirror. I have found preference for thicker clouds and side panels e.g. 3 inch HF MiniTrap with gap behind or GIK traps which incorporate an airgap. The cloud is hard to do but worth it, especially if you have a hard floor.

Many people I would trust have said that Diffusors are not appropriate in small rooms at short distances. Some might disagree. One way of hedging your bets would be to include some wood strips across the front of your SuperChunks. John Sayers Productions has many pictures of John's designs which have such wood strips.

Chris at FuzzMeasure is very helpful. I am sure he would send or give you access to a legacy version of FM. If that is not possible, ask him for permission for me to send you mine ( FM2) which should work fine.

Best, Dan FitzGerald
Sound Sound - Homepage

[los marbles]

Many thanks DanDan

I emailed Chris to ask for his advice, and I had a sneaky feeling that I would be a little over my head with the analysis like you said. If Chris supplies me with some software, great...I will see what I can learn from it. I mentioned that if he was unable to supply an older version of his software if it would be ok for you to send me a copy. That is a generous offer. I'll see what he says about that and keep you posted.

I do have a hard floor and will take you advice re: the clouds. I will likely be building all these units myself, as I am saving up for some other hardware.

I am looking at roxul products that are available here in Canada. I have researched some frame designs and I am compiling information on their construction.

Your words: "Bass Trap as many corners as you can, with the biggest Bass Traps practical. There is no maximum amount. Most is best." seem to ring true with other perspectives on my situation and that is the philosophy I am garnering.

Thanks again!

[los marbles]

Also, I checked the John Sayers site (very inspiring BTW) and I see this type of design re: the wood strips.

Is this what you are referring? Would I vary the number of strips to achieve different results? I have heard that craft paper on the Owens Korning gives this effect as well. His examples show a lot of coverage on his traps (or maybe this image is not an example of what you are talking about?)

[Ethan Winer]

Originally Posted by los marbles

Your words: "Bass Trap as many corners as you can, with the biggest Bass Traps practical. There is no maximum amount. Most is best."

Yes, and it's not really even necessary to measure at all. It's not like you have to measure to know what treatment is needed. The main reason I suggest people measure their room is to give them a wake-up call, so they can see how bad their small room really is. Most people argue over 0.001 percent distortion in this A/D converter or that, ignoring literally 30+ dB peaks/ null spans in their room.

--Ethan

[DanDan]

Y'All. Yes that is the wood effect I was referring to. I would be inclined to vary the strips and the gaps. Random is fine. There is a great side benefit here, you are not relying so much on the fabric for containment and aesthetics. His designs do show a lot of coverage. I would opt for a good deal less. 50-50 perhaps. Thin light wood will vibrate with bass and probably have some beneficial effect. I would rather the random and diffusing action of these strips over Kraft paper or other membranes.
A recent thread here identified Roxul HT as the least health threatening absorbent available. Between that, a stable banking system, and great health care, you Canadians are lucky!
Best DD

[los marbles]

Originally Posted by Ethan Winer

Yes, and it's not really even necessary to measure at all. It's not like you have to measure to know what treatment is needed. The main reason I suggest people measure their room is to give them a wake-up call, so they can see how bad their small room really is. Most people argue over 0.001 percent distortion in this A/D converter or that, ignoring literally 30+ dB peaks/ null spans in their room.

--Ethan

Hi Ethan, thanks for taking the time to reply to my post. In doing some online research, I stumbled across your video series and the one about resonance and ringing brought shivers to my spine...and thank you.

This was exactly the type of problem (modal ringing) I just experienced doing my first mix session in this new location (small room). I was having immense problems with several bass tracks that the artist paid good money to have on his record, and here I am automating his tracks (spending hours) bringing up certain notes, dropping others, knowing that there is a problem in my room the whole time. Sweating bullets.

You can imagine the effect my work had as it translated to other speakers.

The "one note bass" was all over the place. Your example using the click really demonstrated the point all to well.

I knew my chain was good, great player, well captured bass (I've done this enough) but not fully understanding what the exact problem was.

Well, now I know, and I'm on the case. Problem soon to be solved.

Thanks for making your wealth of knowledge easily accessible, and understandable, on the net.

[los marbles]

I have to act now on my treatment as I have about 3 weeks off before I start 3 big projects (at once) in early January. I am hoping for any advice on my traps/placement/amount.

I am going all DIY because I want to save some cash (my wife is expecting, holidays, bills, bills, bills...).

My traps are going to be 6" deep, cedar frames (I can get the boards cheap), with landscaping fabric stapled tight to the outsides, holding in 2 layers of roxul sn's 3.5" (compressed slightly to fit in the 6" frames). I will mount those a few inches from the walls, corner traps (floor to ceiling) will be angled in the corners with the edges against the two walls that meet.

All traps are 24" wide to accommodate a good fit with the roxul.

I am going to experiment with wood slats on some traps like Dan Dan mentioned.

Because of my small room size, all info I've read indicates I must go over the top with lots of bass traps. I am building 16 in total.

The corner where the door is might require another trap on the door itself as the corner trap won't be able to angle out from the wall without blocking it.

There is a diagram in the OP of my room, and I've attached I plan that I am using to figure the amount of traps I think I need. It is to scale, as in the door, closet, windows, trap size are all relative to the wall dimensions.

If any of the experience people have the time to take a look, please let me know if I am going in the right direction here.

My questions are:

Is 6" thick overkill?
Is my placement OK (I can cover the window if necessary)
Is my "cloud" substantial enough? I have a hard floor.

I'm sure I will have more questions as I build these starting later this week. Thanks in advance to anyone who may take the time to help me out with this!

[The MPCist]

FWIW, I have a few friends who just hook up a flat mic to PT, insert a Spectrum Analyzer plugin, and run pink noise.

Worth a try....

[recall]

I have been playing around with DUY-31 ANALYZER/GRAPHIC EQ over the weekend. I have it on demo at the moment. it generates pink noise from pro tools you record this back into pro tools with the graphic eq analyzing the recording. It automatically adjusts the the EQ to compensate for room issues. I guess the idea is to place this eq on the master bus with the settings it has captured. I don't like the idea myself, but it did give me some interesting info about my room. I have a big null at around 400hz which it is compensating for.

I have been trying to use REQ Wizard all morning with my 002r but I can't really get my head around it really.

I'm in the same boat as you. Fuzzmeasure looks great but will no run on my tiger setup.

[DanDan]

The plan looks pretty good. I am glad that you are taking all the advice literally. It will work and you will be delighted.
I have a couple of changes though.

Frames
A solid frame covers quite an amount of surface area. This diminishes the effect of your Traps. RealTraps and GIK's have perforated frames. There are various shots at DIY frames at studiotips. One in particular used standard hang ceiling metal to construct perforated frames. Pretty much a copy of the commercial ones.

Bass Traps
6 inches is good. It would be beneficial to use Fibre Batts with FRK facing. I don't know the density of Roxul s n s and I wonder is it stiff enough. Note that 705 is 6 lbs per cubic foot which is approx 96kG/cubic metre. I think Roxul HT80 is similar.
These dense boards are easy to work with and don't sag.
They can be actually stiff enough to use simply wrapped in fabric. A little area of resin can form hard hanging spots in the fibre. No frame. You need to get hold of one panel to feel this out, experiment.
Having said all that, Superchunks would perform much better and use the much lighter and cheaper 703 sns etc. There are also less attachment and framing issues.
Regarding the Door/CornerTrap conflict. A six inch panel flat in the corner is much better than none. If it is practical, consider leaving the door open when mixing. An opening has great absorption figures.


RFZ
3.5 inches is plenty. No FRK. Hang them out from the wall 3.5 inches or so. Again you need to feel this out and chose an optimum density which won't sag or else use a more supportive but perforated frame. Ethan and Glenn have done their homework!
Double the cloud, no doubt- Four Traps.
Use the Mirror to find spots for the side Traps.
Has that closet a door? Remove it? and replace with a heavy curtain or hanging.
Hang a thick wool piece of wall art on the doors.

Front and Back Walls.
We have dealt with certainties up to now. From here on some experimentation is needed to identify where to put Traps, or not.
Ethan has an article somewhere about treating the front wall, or not. I wouldn't unless you have a good reason. One such reason would be a flutter echo between front and back walls. Use sharp handclaps to trigger these. Get a friend to temporarily hold a panel in place to kill that echo. Hang the trap there. A couple of lighter traps on just one of the two walls should sort that out. At this stage it is a matter of tweaking and seasoning to taste. Here's a design I did for LittleDylan Studios. The owner, Brendan, finally chose to use SuperChunks to save money. They are delighted with the results.
Good luck, DD

[memphisindie]

FFtea and an interface with a flat mic.
studiotoolz » Spectrum Analyzer

[los marbles]

Thanks again DanDan.

The framing idea is excellent...I am having trouble finding the page at studio tips, I need to see/read about how to construct this. I was going to cut out holes in the wood frames, but this idea is better.

I am not exactly clear what "superchunks" means...but from reading a bit at studiotips, I think it refers to a technique of creating a wedge by cutting triangles out of rockwool and fitting them into a corner. That would take up less space and sounds more efficient.

I am leaning towards Roxul sn's for a few reasons, easy to get where I am, Home Depot carries it for a $30/bag (60ft2). I called every hardware/building supply store I could find in my area and no one carries the rockboard. From what I've read, it is cheaper than the Owens Corning and specs out the same. It's also safe.

I figure if it can stand in a wall between two studs, it can stand in a frame supported by fabric, even some insulation adhesive to help. Maybe not?

I don't know what Roxul HT80 is. I checked their products list (Rockboard 80?)

I am all ears if there is a better solution that is $ effective.

I will double the ceiling traps as you say.

There is no door on the closet, just a heavy cloth hanging there.

I can do the same for the door. I do leave it open when I mix and I notice a difference in here when I close it.

I will read more on the front wall situation later today.

Cheers DanDan (and everyone else who posted here)

I have some clients coming over and I have to clean up a bit...

[DanDan]

Superchunks Acoustics Forum • View topic - Studiotips SuperChunk
Superchunks rule. GIK TriTraps seem similar

A wooden open frame design, again very GIK
http://www.bobgolds.com/TrapKiwishred/home.htm

Bob's site also has absorption coefficients for most fibres including all the Roxuls.

Safe and Sound will be fine in a SuperChunk. Not sure if it will sag or not in frames. There is always the balance between rigidity and availability.
Always.

Some great deeper info at Ethan Winer - Home Page

I have contacted Chris at Fuzz, encouraging him to make an earlier FM available for the many of us who haven't gone to Leopard yet. He always delivers.

Best, DD

[Ethan Winer]

Originally Posted by DanDan

Ethan has an article somewhere about treating the front wall, or not.

Here you go:

Front Wall Absorption

--Ethan

[los marbles]

Originally Posted by Ethan Winer

Here you go:

Front Wall Absorption

--Ethan

Interesting. It would seem from your article that there is not enough volume (at low listening volume) escaping the back of the speakers to really impact the listening position.

Is this only true in larger rooms? How about a small room like mine where I may only be about 4 feet from the front wall?

Thanks Ethan.

[Ethan Winer]

Originally Posted by los marbles

How about a small room like mine where I may only be about 4 feet from the front wall?

Same thing. The rear wall behind you is a much more important source of early reflections. This is not to say that absorption in the front is never useful. It can be as valid a place as anywhere else for general ambience reduction. But it's not a direct reflection point for the speakers. And if you absorb the rear wall, sound won't bounce off that wall back toward the front.

--Ethan

[los marbles]

Putting together the guidance I am recieving here, and the recommended reading, I have made some alterations to my plan. I am building the corner wedges based on this idea:

Corner Traps finally finished! - Home Theater Systems - Electronics and Forum - HomeTheaterShack

I am building traps based on this idea:

Steven P. Helm: DIY Bass Traps

(Thanks DanDan for the links/ideas in the right directions)

Not sure if I mentioned DanDan, Chris got back to me with a version of Fuzzmeasure that works with my OS. I will get more into it once my construction is complete to fine tune things.

I am not putting traps directly behind my speakers, I understand what you're saying Ethan...makes perfect sense to me. If there is an issue, I'll look at it later.

I have attached a revised wall plan and a picture of the corner with my door. I can't get a corner wedge in there. That is in the back of my room so I want good corner trapping. I don't always have the luxury of having my door open. I could either: turn my system around (back is front, visa versa) or come up with another idea (guys?). DanDan mentioned hanging a thick wool cloth on the door, I am worried that wont cut in a small room in such need of tightening up.

My "side left" will be 32" wide, not 24" wide as pictured.

Some the revised plan is based on DanDan's work in the room he attached in his earlier post.

I contacted roxul about the rockboard 60 product for the traps (not the corners, I'll use the sn's for those). Hopefully it prices out ok AND they can ship a small order.

I contacted GIK earlier and they offered to help me with my room, but if I am not purchasing their product, I don't want to waste their time. They seem like great guys though.

Any further thoughts?

[los marbles]

I found a local supplier of fibrex (from a roxul rep oddly). I am posting the specs here because I don't understand the rating (understand the freqs. but not the rating) and hoping someone will take a quick look and give an opinion.

I am going to use it for the traps and use the less denser roxul sn's for the corner wedges as recommended by another source. I read that less than 3lbs/cubic foot is the way to go for those.

[avare]

Originally Posted by los marbles

I found a local supplier of fibrex (from a roxul rep oddly). I am posting the specs here because I don't understand the rating (understand the freqs. but not the rating) and hoping someone will take a quick look and give an opinion.

I am going to use it for the traps and use the less denser roxul sn's for the corner wedges as recommended by another source. I read that less than 3lbs/cubic foot is the way to go for those.

You can use any of them. The best is the 1240. The rating is an average over several frequency bands. Not of value for music absorption purposes.

Andre

[DanDan]

I replied yesterday but it has strangely disappeared.
Trying to remember my comments-
That Superchunk design you found is deceptively clever. Copy it and you won't run into a couple of issues.
The Stephen Helm is the one I couldn't find. Great design also.
The wool art on the door suggestion was to kill flutter echo.
That back door is a pain. However I have done tests recently which showed that opening such a door works well for Bass Trapping, as one would assume.
I would encourage the larger 34 inch wide SuperChunk design.
The Fibrex figures look good to me. I just noticed Andre joining in. He is probably familiar with Fibrex. Hi Andre, will the 40 be stiff enough not to sag in the cloud, or should we go to 60? As always, availability will rule, so at worst you might have to add some very thin supporting struts or wires to your frames. Not the end of the world.
Chris of Fuzz,Measure delivered, as always, thats why I encourage support for him and ETF, rather than the free one.
Little options- Two Bass Traps across the Back Wall Ceiling corner?
One more Bass Trap on the Front Wall Ceiling Corner.

Good luck with it.
DD

[los marbles]

What an education I'm getting....

Andre...Thanks for chiming in, appreciated: I just talked to Mike at Fibrex and he tells me the density for the 1240 product is 3lbs/ft3. Sounds light, no? The density increases with the product number, 1280 being the densest.

I am ordering thru a local supplier so I will get what's best based on recommendations from more knowledgable people (namely YOU) I can even get it FRK faced by my supplier here.

If all the density affects is the sag factor, attaching a few wires for braces seems like little trouble.

DanDan, I will follow your recommendations with the ceiling corners. As I can't have my door open all the time, I was thinking of a four inch thick trap (not a corner wedge, but a framed trap) that sits against the wall in the corner. It could have a small air gap from the back wall of 1" and it wouldn't be angled out. It would parallel that wall. Please check out my idea sketch. I will cover the door with something as well for the reflections.

I can do 34" superchunk in two corners, The closet opening is only 16" away from the front right corner, I could get away with the 17" side that a 24" superchunk face would provide, but any bigger would be sticking out too far into the closet entrance. I have a tape machine parked there.

Can I fish any more of your valuable time for comments?

[DanDan]

I think by all this careful consideration you have come up with an optimum design. I get more education every time I do this also.
Do remember when you are itching and cussing, it will work- spectacularly.
The 4 inch panel by the door is a good idea, as is the gap behind. I may have mentioned FRK before. On consideration, forget that. I have noticed frequently that Rockwool (Fibrex is similar) is specified for acoustic work at higher densities than FibreGlass. I don't know why that is. Perhaps FibreGlass has longer fibres and is more 'efficient'. I would be very interested to hear the answer to this from someone more knowledgeable than me. Because of this I guess the higher densities of the Fibrex seem appropriate, even the 80, which might eliminate the need for supports. I would defer to Andre's wisdom on this, as he probably knows Fibrex. Judge the gap over your cloud well. Bigger is better of course but the room needs to feel good. Speaking of which. I have installed CFL bulbs, which don't get too hot, behind Traps, with a spectacular Lighting effect.
You can see that at Sound Sound - Gear
Very disturbingly this cheap effect gets more positive comments than my treasured but ugly V76 preamp!
Best Regards, DD

[Ethan Winer]

Originally Posted by DanDan

I have installed CFL bulbs, which don't get too hot, behind Traps, with a spectacular Lighting effect.

Awesome Dan! I too have lights behind many of the panels in my living room, but they're regular incandescents on a Variac dimmer. Usually kept very dim for watching movies etc.

--Ethan

[los marbles]

I love the light idea too, I was wondering what to do about my ceiling light. Now it's a bonus as opposed to a pain to deal with.

Thanks alot everyone (especially DanDan) for all your help. I only have a few weeks off before I start 3 big projects at once so I have to get building.

I do a lot of video game audio in this tiny room, but I also do some small budget records and I also have a film score coming up in january.

I will likely have a few more questions as the build goes on...

Cheers!

[DanDan]

Hi Ethan, LM, I know, the Lights! They get more attention than 100K of dream recording equipment! Thanks for the kind comments. I am looking forward to hearing from LM again when the room is done.
Happy Christmas, DD

[AudioWarehouse]

Originally Posted by DanDan

Bass Trap as many corners as you can, with the biggest Bass Traps practical. There is no maximum amount. Most is best.

Dan,

What's the science behind this?

I think you'd agree you can have 'too much' mid/hi absorption leaving a 'too dry' acoustic (what the 'too dry' is is for another day's discussion) so why shouldn't that be the case with low end i.e excessive bass trapping with drop the low end RT down too much?

[Ethan Winer]

Originally Posted by AudioWarehouse

why shouldn't that be the case with low end i.e excessive bass trapping with drop the low end RT down too much?

This is very simple really. Peaks and nulls and ringing at mid and high frequencies are easy to totally tame using relatively thin absorption. Diffusors can be helpful too in larger spaces. But low frequencies are very difficult to fix. Even if you pack 20 bass traps into a bedroom size control room, there will still be peaks and nulls and ringing. So not only can you not have too much bass trapping in a typical size room, it's very difficult to even have enough.

Also, small rooms don't really have reverb unless the entire room is totally bare. It's more like a few individual echoes that decay fairly quickly. So let's call it ambience. Small room ambience does not generally sound very good, so it's best to kill it. Or you can use diffusion to reduce the coherence of the echoes so it's more like true reverb than metallic sounding flutter. But diffusion is a mid/high frequency issue. You can't really break up bass waves that way.

--Ethan