its a nice change isnt it?

i wrapped mine in guilford of maine cloth, and they look identical to the GIK panels they are "copying".

tape op had a design for a cheap diffuser out of 2x2's and a backing board. mayby try those along the longer more open areas?

http://tapeop.com/articles/83/diy-diffusors/

Cool, this will make big changes in your enjoyment and sound! I could be way off on this but, if you feel you aren't tight enough and can't get more treatment, mix at lower volumes. Works wonders.

audiokid, post: 415190, member: 1 wrote: I could be way off on this but, if you feel you aren't tight enough and can't get more treatment, mix at lower volumes. Works wonders.

It's not that I can't get more treatment, it's that I'm not sure if I need anymore, although guys like Ethan Winer will tell you that you can never have enough bass absorption. ;)

And I've always mixed at volumes much lower than most of my peers, turning up occasionally to check certain details in the mix, but then I'm back down to around 75 db again.

I guess my question at this juncture is if I do in fact need to add more treatment?

If my mixes are translating well to other playback mediums outside of the control room, wouldn't this be the best indicator, the best proof that what I've done is effective?

I have treatment material left over. I just don't know that I need it, if what I'm hearing now sounds as good as it does.

Isn't the whole goal of acoustic treatment to insure that what you mix and hear in your environment translates accurately to other outside systems?

What else could I do that wouldn't perhaps start to become a detriment? While Ethan has stated many times that it's not possible to ever have too much low end treatment, I know it's true that you can in fact have too much of mid and hi frequency absorption. I want an accurate environment, but I don't want an anechoic chamber, either. And, I don't want too top end absorption where I could get to the point of having my mixes come out as hi frequency heavy, either, which could happen, if I had too much absorption at those frequencies...

Just kinda think' out loud, here...

d/

Josh Conley, post: 415181, member: 47953 wrote: its a nice change isnt it?

i wrapped mine in guilford of maine cloth, and they look identical to the GIK panels they are "copying".

tape op had a design for a cheap diffuser out of 2x2's and a backing board. mayby try those along the longer more open areas?

http://tapeop.com/articles/83/diy-diffusors/

I've already got a diffuser built, Josh. It's a 2 x 2 skyline RPG pattern, using various lengths of 2" x 2" pieces, from 1" to 4" high, placed (attached) to a 2'x2' base-plate. This was based on a design I downloaded about a year ago, and it may in fact have come from TapeOp. I think it may have even originally been a Massenburg design.

Although, my recent research has shown that diffusion is not always a "must have". It depends greatly on the dimensions of the room, and what frequencies are still problematic after absorption treatment has been installed. So, there's a chance I might not even end up installing it.

By professional standards, my mixing room is quite small - 14' 6" L x 12' 3" W x 7' 11" H - and as we all know, the smaller the room, the harder it is to successfully treat.

But, I am happy with the results I've gotten so far.

I have not sound PROOFED the room. Honestly? I don't even have any plans to do so. This would involve rebuilding the room from a structural and material replacement level, and not only do I not have the funds for that, it's really not a major concern for me. I'm far less concerned about sound leakage and transmission than I am with creating an accurate mixing environment.
I honestly don't care if a truck goes down the road in front of my house and I hear it, nor do I care about sonically isolating myself from my neighbors.

I'm still researching. I'll be glad to post updates and explain what I've done - both positive and negative, if you guys want me to.

:)

d/

I have 13 RealTraps plus foam and could have double the traps but I'm happy with what I have now. Where I sit or move around my ring is great. Thats how you will know. If I walk around my room is sounds pretty consistent everywhere too but there are still spots where I hear the bass needs more. Everything from treatment to where you position monitoring and sitting position counts. Use a measurement utility to see how it scopes out.

Here's how my room looks ( at mixing position) with 13 Traps. My room isn't ideal either.

pretty sweet looking.

how much does that thing weigh, and how do you plan to mount it?
Did you attach each piece to the one next to it, or just to the backing board, and how?
Since I'm an engineer (no, the other kind) I'm very curious about how much that backing board will flex with all that weight attached to it, expecially considering it will be built laying flat, but it will be hung -bascially sideways- for many many years.

I've been thinking about making one since I read that tape op article, so maybe I'll get to it in the next 5 years ;) lol.

Cool stuff D. I'd say now is a good time to test the room, or if your are thinking of more broadband bass traps, put them in. anything beyond the mirror points and any addition broadband bass, is going to be unique to your room, and probably more narrowband in nature. this is where your talking resonators, and other traps of this nature. also dont forget the poor mans bass trap, the open door and window.

as far as sound "proofing", the better your isolation, the worse the acoustics. the typical air gaps, and thin walls, in residential construction, let the mids/highs out, and the walls aren't massive enough to contain the lows. so from an acoustic standpoint, its not a bad thing that your in a room like yours.

theres really no way to recommend more treatment, w out knowing what needs to be treated, frequency-wise.

ive never heard any acoustician say you could have too much bass trapping in small rooms. i think off the top of my head, in general its something like 20-35 percent, of the surface area in a CR should be absorption, which some people find a bit too dead, thats a rough quote from rods book, which i don't have w me right now. ill have to double check the number, but it seems like your happy w the mids and highs, and questioning bass. ?

i would imagine, the safest way to go w no testing, would be more bass traps.

that diffusor looks awesome man. great work!

the best sounding CR ive been in is the one, in my icon pic, it has 8 ft of bass trapping area behind the rear wall.

honestly, the most noticeable thing about it, is the imaging. it holds up very well, pretty much anywhere in the room. as well as the bass. i dont have any test data yet, so i cannot comment on its actual response, but the consistency is quite remarkable.

ive had the privilege of listening in this room through the project as the equipment moved in, and monitor controllers, and EQ on the mains. i very very strongly disagree w/ a senior co worker (former owner) that his use of EQ actually improved the sounds. this is from a listening perspective, not mix, and the eq while, technically made the room flatter according to the RTA device, it made things just sound wierd. granted, this guy has insane peaks and valleys on the eq, which, of course isn;t generally whats recommend w eq. it should be only a couple of frequencies, and not much at all of it, if you use it at all. frankly, it sounds better, (more full, and more like the outside world), and its an expensive EQ but i think this guys looking to reinvent the glory days, and also, just be able to say the room is 'flat''. when i finally finish up the re model, l'll post some tests, cuz i think are much more reliable testing methods, than an RTA from the 80s, which requires you to wwave the test mic (earthworks) in a circular polishing motion, while it quantifies.

glad to hear your liking your room improvements!!!!!!!

What I noticed right away was imaging and detail - for the better... far better. ;)

I'm hearing things that are now far more defined and detailed, particularly down low with the bass guitar and kick, as well as in those upper esoteric areas of "silk" and "air".

Also, one other result I hadn't counted on - or had perhaps forgotten - is that I'm using far lesser amounts of changes to get the desired results than I used to. For example, cutting or adding EQ by just the slightest bit can be heard very clearly now, as opposed to my untreated area, where it sometimes seemed as if my changes weren't even doing anything.

Now, after treatment, if I sculpt tones in the low end, or, add silk in the top, I can hear the results far more easily, quicker, and am using much less of it to get the desired results.

I really am very happy with where I am right now...and I'm not sure I'm concerned about low end at all, really. I have an open doorway behind me, and a window in front of me that I can open at any time.

My statement of there not being such a thingas having too much bass trapping came from Ethan Winer. Now to be more accurate and to put it into the correct context, what he actually said was that in a room as small as mine, there was no such thing as having too much bass trapping.

I've read that having these open areas will provide up to 1 Sabine of low frequency trapping, with the Sabine being the measurement relative to absorption coefficients, which are measured in increments from 0 to 1. 1.00 indicates a value relative to full absorption . Now, I don't know if that's true, I'd have to wait for Rod or Space or one of our other bad ass acoustics experts to chime in on this... but, there's nothing I can do about the doorway anyway. It's an old house with "coffin shaped" doorways from room to room. I suppose I could get a custom cut door installed, but again, not sure I'd really want to, especially if the open door or window is providing that much efficiency in low end absorption.

This has been a cool project and I've earned a lot through research and application. It's very cool when you do a project like this and can actually hear the results, and brother, I'm not just talking about minimal results, either. The sonic difference in this room is like night and day. It's not even the same room anymore.

Josh Conley, post: 415205, member: 47953 wrote: pretty sweet looking.

how much does that thing weigh, and how do you plan to mount it?
Did you attach each piece to the one next to it, or just to the backing board, and how?
Since I'm an engineer (no, the other kind) I'm very curious about how much that backing board will flex with all that weight attached to it, expecially considering it will be built laying flat, but it will be hung -bascially sideways- for many many years.

I've been thinking about making one since I read that tape op article, so maybe I'll get to it in the next 5 years ;) lol.

The backing board you currently see holding the various sized pieces of wood is not the one I will use - at least not alone - to attach to the wall. This was used strictly as a template from which I followed the blueprints of where to place and attach each piece.

The template board will be attached to a piece of 3/4" ply, which will then be anchored - (heavily anchored, LOL.. I was jackpot lucky and found two verticle studs on 16" centers) to the wall with a piece of acoustic rubber under-layment between the diffuser and the wall itself. I didn't just randomly choose this material... this was what was recommended with the diffuser plans.

This is a web picture of the type of insulating material I will use between the wall and the diffuser.

But.... here's the thing, after all of the labor it took to make the thing, I'm still not 100% positive that I need it. If I end up not using it, I guess I can always sel it, but this beast isn't going by standard USPS Ground.

I haven't weighed it yet, but it's not light. A wagered guess would be 75 lbs, more or less. Before I hang it, I'm gonna need to get an exact number (after I attach the piece of 3/4" ply to it) so that I can get the proper rating for the right type of anchors.

FWIW

d./

Ain't making your own acoustic stuff for your studio fun? Far more gratifying building it than just buying it. I think? I had to come up with some new ideas when my SONEX finally rotted and turning to dust after about 15 years. And I had no budget. Like zero. So ya go to industrial centers/complexes and retail shopping centers and start combing through trash dumpsters. It's amazing the quality materials you can find! And the best of recycling and lowering our green footprint. There is no shame in doing that. It's something to be proud of in fact for doing. At least in my book. The more we can recycle. The happier I get. The more prebuilt stuff ya buy? The more concerned I become for the planet's well-being. Sure everybody needs to make a living. But figuring things out for yourself is the mark of a real engineer and not a wannabe knob twiddling, computer gaming, adolescent. It's becoming something of a lost art. Like actually playing music that doesn't require software to fix. Like singing in tune because you are good and not a fraud like so many.

Guys like Ethan and Rod, no doubt, know, good from bad. They know acoustics. And their knowledge, services and experience are therefore ya if ya need it. Not all of us need it. No we don't do everything right. I'm not an acoustic engineer. I'm a hack. But I'm a good hack. So is Donny. So are many others here like Mad Max, Boswell, Chris and many others here. All professionals. All people I hold in high regards and esteem. They are all far more knowledgeable about accuracy than I am. But that's okay. In many ways, really nothing much matters except your skills. The equipment is actually secondary though others will certainly argue that. And their arguments are valid. But I don't live that way myself. I want to live longer LOL. So I don't stress over that which I can't fix or can afford to fix. That's where I shine. I'm the Queen of workarounds. No LOL... I'm not gay but I could be even if I'm not. But I am a Queen for lack of a better term. Maybe JAP à la Jewish-American Princess even though I'm an agnostic LMAO. Yeah I could lose a few grounds there. And a facelift wouldn't be bad either. But my facility is more important. I like to ingratiate myself with things and be a narcissist. But that doesn't really get ya anywhere. Well... maybe it does for the Kardassians? Especially when you marry a wrapper I mean, a rapper. (He is wrapped with money)

I had fun watching that film by Dave Grohl called Sound City. It certainly presents some very compelling information regarding studio acoustics and who designs them or doesn't design them. Everything that was wrong with that room of that studio is what was right about it. It was supposed to be bad. It was bad. But it wasn't bad. In fact it was great for what it was doing and the people it was doing it for. There is haphazard acoustics at its best! All ya want is gigantic drum sounds. And that doesn't come from a dead box with foam thingies all over the place. It doesn't even necessarily come from an acoustically accurate room. Because it's rock 'n roll. And rock 'n roll ain't a Mozart violin Concerto. And even for that Mozart violin Concerto, you'd never do that in a dead box. Though George Massenburg did something like that with his studio, ITI, back in the early 1970s when he tried to record Baroque Bach harpsichord. What a horrible sounding POS that was! At the time his entire large studio was bright pink! And I wouldn't have suggested to anyone to even breathe in there. I mean, you know you're alive in the morning when you all wake up and take a nice big fresh breath of raw Owens Corning Fiberglas. Where the pink panther is smiling at ya because the pink panther likes to breathe pink fiberglass. And of course George is the world Superstar, expert. Guess not? So the guy in 1971 that didn't know how to record Baroque Bach harpsichor, Is recording opera today. Maybe I should give George a lesson? He doesn't have a Grammy nomination for recording opera. I do. And from 22 years ago when I was a much younger scalawag. In my early 30s. He's only now catching up. Think about it LOL. He, might even find out his own equipment doesn't sound good for that genre as it was made for rock 'n roll? So I'm looking forward to see what he comes up with his operatic work? It better not sound like Earth Wind & Fire, like the harpsichord recording, did.

Primal pontification
Mx. Remy Ann David

"I'm far less concerned about sound leakage and transmission than I am with creating an accurate mixing environment."

Well, if you are going for Sun Records environment then stick with it.

Problem as I see it is simple. We live in a cluttered world truly filled with people. And people have kids and people with kids make noise and so do those that live next door to them.

Now I am not saying you need isolation, I am kinda saying you already knew your equipment and now you have touched on basic rfz techniques that allow for less interference of the actual room you are in. Wonderful thing, I remember when I had that experience.

But isolation is part of a good mixing environment. It isn't about leakage outward it is about leakage inward. In any event I am glad you are doing better in your room.

BTW...I am a moderator, not an expert.

Space, post: 415448, member: 32398 wrote:

BTW...I am a moderator, not an expert.

Well, if you're not an expert, then I don't know what the criteria for "expert" is. I've read many of your posts. You state the truth, you back it up with facts. It's been through the research and reading of your posts, along with Rod's - that I have learned the most, and have been able to actually apply principles that have shown obvious audible results.. ( yes, I'm a "lurker" in the acoustics forum LOL)

So, if you're not an expert, then you're certainly the most knowledgeable novice I've ever encountered. ;)

When I mentioned that sound transmission wasn't an issue, I should have elaborated further. I didn't mean to imply that I won't eventually get to that; I do think that it's important. Right now I've spent the funds I had available on the treatment of the room's acoustic signature; but I do have every intention of creating some isolation between me and the outside world as soon as I can afford to do so.

The good news is that I'm not a city dweller. I own my own home which is located in a rural setting, on several acres, so "noise pollution" to me isn't traffic, jack hammers, or even kids playing. My noise pollution is made up of the tree frogs and crickets in my pond out back, the owls that call to each other at night, etc.. My closest neighbor is 1000 yds away from me, and in 20 years of living here, along with rehearsals and recording, I've never had a noise complaint.

I guess what I'm saying is that at this point, my goal is more to be able to offer a well-balanced room in which to mix projects that have already been recorded, as opposed to doing any serious recording...so, at least right now, anyway, isolation is secondary in my hierarchy of needs. ;)

I do wish to express my gratitude to you for your posts, both past and present. I've learned a lot from reading them.

d/

DonnyThompson, post: 415556, member: 46114 wrote: Hello all..

I have been looking at signing up for night classes at a local university (Akron U) that would cover an introduction to acoustics.

The class I am most interested in is named - appropriately - "Introduction To Acoustics", and meets two nights a week for 2 hours, for 3 months. This class is part of a continuing education program, aimed at adults. Some classes are accredited, some are not. I'm looking for the knowledge - as opposed to the paper - so a non-credit course doesn't sway me.
Classes begin in September.

I realize that this is in no way similar to an actual degree in the science of acoustics, but I would like to take his class in the hopes of gaining more knowledge.

I am still trying to find out who the instructor is, and what his/her qualifications are.

The counselor I spoke to told me that I should take a physics refresher course first, and this makes complete sense to me.

Should I also perhaps look at taking a course in geometry or another form of relative math first as well?

It's been a very long time since I was in college, and honestly, having graduated with a Liberal Arts BA (as an English Major) in 1984, I didn't take much math during this time, other than what the requirements stipulated. My grades in basic math - geometry, algebra - were average.

I am also willing to accept the fact that I may be way out of my league here, and that based on my intellect - or lack thereof - particularly in regard to advanced maths like Trigonometry and Calculus, taking these classes could be a lesson in futility. In short, if told by resident experts here that I should forget the idea, then I would take absolutely no offense.

I realize that acoustics is a very complex field of study, and that not just anyone can grasp it.

I really want to try, to at least gain a basic level of knowledge on the subject, but am willing to accept that it may simply not be something I could ever really understand.

My ultimate goal is to be able to understand enough about the subject so that I can apply the knowledge to my own recording and mixing environment. I have no illusions, at 55, of seeking a career in the field.

any suggestions, thoughts?

d/

Space, post: 415566, member: 32398 wrote: An introductory class might get you the basics. But I would suggest that hunger is the best agent towards getting anything a person wants.

Are you still reading books? Do you buy books? Master handbook of acoustics, F. Alton Everest, is introductory all the way to the advanced and I do not know anyone that knows anything in this field that does not own a copy, myself included.

Get Rods book, its kind of a rule around here :)

It does not come fast and it does not come easy but contrary to the saying "acoustics is not intuitive" I say that it makes perfect rational sense once you know what it is you are looking at.

Other books I have and would also recommend:

Building a recording studio, Jeff Cooper (he has answered questions via email that I asked about his work)
Acoustic Design for the Home Studio, Mitch Gallagher
Sound Studio Construction on a budget, F. Alton Everest

If you can't get the basics out of these books, the acoustics 101, then read them again :) I still do :)

avare, post: 415636, member: 17005 wrote: A big +1 to Rod's book and Everest and Pohlmann. Pohlmann did the 4th edition revision as Everst had passed away. An excellent text on architectural acoustics is Architectural Acoustics by Marshall Long. I just noticed while researching this post that there is a 2nd edition. Time to update my library. It is pricy (109$ at Amazon) and worth it!

In terms of practical texts, what ever that means, one of the great texts is Guide to Acoustic Practice by Rose. You can by used copies from Amazon etc for ~$150 or download a pdf copy here:
http://downloads.bbc.co.uk/rd/pubs/archive/pdffiles/architectural-acoustics/bbc_guideacousticpractice.pdf

Enjoy!

Andre

DonnyThompson, post: 415931, member: 46114 wrote: As many here know, I've been in the process of trying to improve the acoustics of the current room I am in.

Last week, due to a family member moving back home (my mom is terminally ill and will now be in her own home with the aid of hospice and nursing) I now have another room I could use as an alternative to the room I am in now.

The reason that the new room interests me is that because measurement wise,
it seems to be fairly close to one of the Sepmeyer ratios; (in my case, it would be Sepmeyer's second ratio) which is:

H X W X L__

1.00 X 1.28 X 1.54

Here are the dimensions of the other room:

H X W X L___
8' X 9' 7" X 11' 8'

Here are the resulting ratios:

H X W X L___
1:0 X 1.22 X 1:48

Ratio Differences:

H X W X L__
-0.00 X -0.06 X -0.06

As you can see, the ratios appear to be very close, BUT... I don't know that they actually are, because I don't know how crucial it is to be exact to these ratios... so that a difference of
something as seemingly small as -0.06 could be a mile off in terms of the equation...and this is what I don't know....is it close enough to consider?

Materials in the other room would be the same as the room I am in now; 1940's Gypsum Board on walls and ceiling, hardwood floors, 2 windows, one entry.

My question is, will moving into this other room be a better situation for me in terms of dimensions, and, would it provide enough of a noticeable benefit to make it worthwhile?

I know very little about "ideal ratios" (although I'm studying as much as I can) so I turn to the experts here to tell me what they think.

I have no problem moving to the new room; nor do I have any objection to re-treating this alternate room accordingly. I guess I'm just looking for input as to whether it would serve enough benefit to make it worthwhile...

Thoughts?

d/

Kurt Foster, post: 415935, member: 7836 wrote: from what i recall reading Donny, [="http://www.acoustic.ua/forms/rr.en.html"]sepmeyer ratios[/]="http://www.acoustic…"]sepmeyer ratios[/] don't have to be exact. it's better to get as close as possible but a little off here or there isn't a deal breaker.

Space, post: 415959, member: 32398 wrote: What I wish you would do, from this point forward, is to keep all posts related to this topic in the same thread. You have said a lot of things over the past month and they are all over the forum.

It would be really,,,really helpful, trust me ;)

Maybe change the thread name to something more accommodating to your situation.

kmetal, post: 415969, member: 37533 wrote: +1 on that, I am thinking of a graphic in Alton Everest's book where it showed the ratios, then the range of areas around that exact ratio that were considered fine. Everyone I've talked to just said that the ratios are a good guideline, but not an end all, be all. I'm far from an expert, but my thought would be when talking rooms of that size, the bigger the better, if for no other reason than a deeper bass response. I'd have to check, but I think it was in that same book, that it said to use the longest dimension, which would be diagonal, to figure out what the lowest frequency your room can contain is. I also might be imagining it in my feeble brain, I'm on two hours sleep after an 18 hr mix session that killed the mixers power supply, so I'm a bit hazy tonight, and probably should not be commenting at all.

DonnyThompson, post: 415974, member: 46114 wrote: You're absolutely right. My apologies. I'm going to limit this to one topic, one thread. Thanks, Space.

Space, post: 415986, member: 32398 wrote: Room ratios have been around for decades and rooms in general have been designed to be pleasing visually and sonically by many builders/ architects. You only have to look around the building you are in right now to recognize this is not something new, it has been around you all your life you just were not aware of this.

The inclusion of room ratios for an acoustical environment is different in that the ratios used have been tested so that the builder has a better starting place than a typical room ratio that a typical builder might use.

Alton Everest ( Master handbook of Acoustics - 4th Edition) presents 3 of the most widely used ratios developed by L.W. Sepmeyer (1965) and M.M. Louden (1971)

Height Width Length

_______________________________ _________

Sepmeyer A. 1.00 1.14 1.39

B. 1.00 1.28 1.54

C. 1.00 1.60 2.33

Louden A 1.00 1.4 1.9

B 1.00 1.3 1.9

C 1.00 1.5 2.5

It must be noted that when these ratios were being tested a ten foot tall ceiling height was assumed. In some detail, we will find out why this was an important aspect to this particular testing procedure.

Based on Loudens first ratio “A”, 1.00, 1.4, 1.9 with a ten foot tall ceiling this would produce a room with the interior finished ceiling height of 10 feet with a interior finished width of 14 feet and a depth of 19 feet. This room will have a volume of 2,660 cubic feet. Plenty of height for the sound to expand and develop and exceeds the 1500 cubic feet room volume limit determined to be the least amount of volume a quality audio environment should have.

(C.L.S. Gilford, Affiliation: British Broadcasting Corporation,“The Acoustic Design of Talks Studios and Listening Rooms” circa 1979, maintained that a “small” room based on the research done would be a room with a volume of 1500 cubic feet. Further he states “It is shown that a distinctive characteristic is that, because their dimensions are comparable with the wavelength of low-frequency sound, the sound field is characterized by strong simple standing-wave patterns which cannot be eliminated without eliminating the reverberation itself. It is shown also that for the audible effects are confined to those associated with simple axial modes and that, by careful adjustment of dimensions, provision of diffusion and the proper distribution of absorbing material, the worst faults can be avoided. “)

An interesting thing happens when we look deeper into these ratios, when we look at the single components of the room and not the end result.

The speed of sound at sea-level is considered to be 1,130 feet per second and in order to get the fundamental frequency of the height or width or length we have to use the equation F=1,130/2xD.

The height of ten feet using the above equation will produce: 1,130/20=56.5Hz. This is important to know since 56.5 Hz relates to the note A1. It actually falls 1.5Hz past the frequency of 55Hz.

The width of 14 feet using the equation F=1,130/2xD (1,130/2x14(28)) = 40.36Hz which closely correlates to 41.20Hz or E1 on a midi keyboard.

The remaining length measurement 19 feet X 2 = 38 produces 1,130/38=29.74Hz, relates closely to 29.14 (A#0/Bb0)

Using the 8 foot ceiling height and Loudens first ratio produces a room 8 feet tall, 11 feet and a few inches wide and 15 feet and a few inches deep. That is about the size of a typical bedroom or the living room in some homes.

The consideration for having a balanced proportional room is valid and worth the effort to use in any sound related type room. A few things to consider along the way. The measurements that are obtained from the ratios define the interior side of the wall.

In order to use these measurements, you must determine how much and of what thickness your interior sheathing will be. This allows you to step out the placement of the sheetrock or MDF/OSB or whatever combination you may use, in order to establish were the actual framing will be placed on the floor of your build.

To that end, ratios are not scalable...they cannot be modified and expect the same results: [[url=http://="http://www.acoustic…"]Room Sizing Tutorial | Acoustics, Audio and Video | University of Salford[/]="http://www.acoustic…"]Room Sizing Tutorial | Acoustics, Audio and Video | University of Salford[/]

DonnyThompson, post: 415996, member: 46114 wrote: This is an awesome post, Space.

Things I found very helpful - and very interesting:

"Based on Loudens first ratio “A”, 1.00, 1.4, 1.9 with a ten foot tall ceiling this would produce a room with the interior finished ceiling height of 10 feet with a interior finished width of 14 feet and a depth of 19 feet. This room will have a volume of 2,660 cubic feet. Plenty of height for the sound to expand and develop and exceeds the 1500 cubic feet room volume limit determined to be the least amount of volume a quality audio environment should have."

"The consideration for having a balanced proportional room is valid and worth the effort to use in any sound related type room. A few things to consider along the way. The measurements that are obtained from the ratios define the interior side of the wall."

I'm going to attempt to merge all these different threads/subjects into one thread/topic.

DonnyThompson, post: 415485, member: 46114 wrote: Okay... so I've been researching poly-cylindrical diffusors...

Someone check me on this please:

From what I understand, diffusion itself does not lessen the energy of frequencies, but instead, actually creates more reflection(s)... but in doing so, it lessens the intensity of these frequencies.
The smaller, scattered frequencies will have random phase as a result of their individual and random "throw" around the room, and this can result in a smoother RT decay curve in the room.

So first of all, am I correct in the basic understanding of a diffuser's main purpose?

---------------------------------------------------
Here are some details about the room, should they be required:

Room Materials:

older type sheet rock on the walls and ceiling. The house was built in the 1940's. There is insulation in the walls, although not much. It appears to me to be the cheap blown-in style of material. Between the ceiling and the floor upstairs, there is OC R19. (I know this because I put it in myself).

The floor is hard wood - oak, stained and sealed.

There is one door, pretty sure it's pine, stained and sealed.

There are two windows - L 52" x W 32"; both are newer (within the last 4 years) double pane, energy efficient.

Room dimensions:

14' 6" L x 12' 3" W x 7' 11" H

Splay:

The walls on both the L and W dimensions vary from end to end by up to two inches.
The floor and the ceiling differ in height by 2 inches... but not on an end to end basis. The difference is in the middle of the room where either the floor has settled or the ceiling has sagged.

So the room is not exactly square.
------------------------------------------------------

The most obvious question is, do I need diffusion of any type at all?

If the answer to this is yes, or probably, then I'll continue...

Before I continue with my questions, I should tell you that I have been doing a lot of research on my own... I'm not trying to be lazy here. I have looked on the web to find the answers to these questions, but I've either not been able to find the answers, or I have run into contradictory information. It's also very possile that I'm not asking the correct questions... That being said...

If diffusion would be beneficial in my situation...

1. would I be better off using a poly-cylindrical form of diffusion as opposed to the "skyline" type that I have already built?

2. if I can - or should - consider using poly diffusion in my room, does anyone know where I could find the formula needed to calculate the size and/or amount of the poly cylindrical diffusion that I need... width, depth, curve, etc.

3. can I make a diffuser of this type that serves 2 separate purposes - those being diffusion and absorption?

For example, along the wall behind me, where the wall meets the ceiling, could I run a 12' length of poly diffusion along this section, but in doing so, also add absorption material inside the diffuser?

If this is possible - because I'm dealing with a half cylinder shape - I would think that something like Roxul would be better to use, than trying to fit and meld rigid glass with the shape... (and also allowing myself enough room for a 2" air gap between the insulation and the wall).

Would any of this serve a purpose that would be worthwhile? Or am I into a more esoteric type of treatment which leans towards diminishing return?

Any info would be greatly appreciated ;)

d/

.

Audiofreek, post: 415988, member: 45862 wrote: Poly cylindrical diffusers aren't really that complicated. They are the poor mans solution to diffusion, and there is no formula per say, but it is nessesary to put some fluffy insulation behind them to dampen any resonances if you are sealing off the tops and bottoms. If you have the time and patience to build skyline diffusers they do a much better job at actual diffusion, rather than just scattering the reflections. I guess you could calculate the resonance of the diffuser if it is sealed, and tune it to trap a specific frequency as well. They do not have to be one half of a circle, they can be bent into a gentle arc as well. It it not recommended the two be placed side by side without any gap as they create a focusing parabolic effect. If you need to place them side by side some absorption between.

kmetal, post: 415990, member: 37533 wrote: I'm not aware of any sort of calculations or formulas for diffusion, as there are for like absorbstion coefficients. I think it gets pretty complicated pretty fast, and I've never seen anything like that in any of the books I've read. Although I do believe there are requirements for the volume (physical room volume) for you to actually achieve a "truly" diffuse environment/diffusion. You really should check your local library d, and see if they have the master handbook of acoustics, by f Alton Everest. That's where I got it, and had it for a few years lol. It covers a lot of the stuff you've been investigating lately, and you don't need a PhD to understand it.

I'd really be more concerned about bass trapping, than management of the mids highs. What you have built already for diffusors is probably gonna be just fine, considering the size of the room.

Audiofreek, post: 416000, member: 45862 wrote: There will be some absorption with the type of polys I have seen. The thin 1/8th plywood will allow bass to penetrate and be absorbed somewhat by the fluffy fibreglass,as well a consuming some energy while entering and exiting the diffuser.Mids and highs will bounce off, but who knows what the cut off frequency will be, and phase relationships at the the cross over point will have changed, due to the exiting waves starting at zero, and the reflected waves keeping the same relationship with themselves.

My original intent in asking about poly cylindrical diffusion, was to treat the areas where the wall corners meet the ceiling - which is a corner in itself.

Through my recent research, I don't believe that my room is big enough to take advantage of the potential benefits of diffusion.. In fact, it falls far below the minimums that I have researched.

As of this writing, and from what I learned thus far, I think that I should stick with absorption as the main element of treatment - broadband and corner bass trap treatments.

Although, I'm perfectly happy to be told that my theory is flawed and that I'm wrong. ;)

I am picking up Rod's book this week, and Andre has been kind enough to send me some info that I plan on beginning to study this weekend.

Sooner or later, I'm gonna start to grasp this.

Update:

One of the benefits I've noticed as a result of my recent treatment is with tracking. I recorded a friend's vocal in my mix space last week, I had him stand near the center of the room, distance to mic was around 5-6 inches, with a broadband cloud directly above him, broadband panels on either side of him (wall mounted), hardwood flooring. The track came out sounding very nice; smooth, warm, with a nice edgy presence - but it was good edgy presence... the pleasing kind without harsh/peaky transients. It didn't sound "dead"- it sounded real. Nice detail, air and silk. It was a very "listenable" track.

Of course, this is a testament to his voice and his mic technique as well, he's a veteran, so he knows how to "work" the mic.

I needed to use very little EQ - besides my go-to HPF - which I pretty much assign to everything, the frequencies of which varies from track to track - it required just a bit of attenuation around his personal sibilant range
(-3db @ 4.7k ). I also used some smooth, gentle compression, ( Eventide Ultrachannel, 3:1, -10db, 20ms attack, 150 ms release, little-to-no makeup gain) but beyond that, I really didn't need to do anything else to it. Besides the obvious benefits regarding mixing, I can only assume that the treatment I've installed in the room has also resulted in a nicer room for tracking - at least for vocals, anyway.

We tried two mics on his voice, an AKG 414EB and a Neumann U89. While very similar, the 89 worked better for him on this particular track (with my own voice I prefer the 414EB) although that could certainly change as range and song styles do.

I'm working on a rough mix now and will post samples in the next few days.

06/22/2014 Update:

Some observations regarding the recent treatment:

Translation

A vast improvement on the translation of my mixes to playback systems outside my mixing space. Much more accuracy. ( Of course, the downside to being this accurate is that bad mixes are clearly obvious as well.) ;)

Imaging

I'm hearing far more detail in mixes, both L to R and in Depth as well. This detail became most apparent after installing the cloud above my mix position.

Tone

I find myself having to use far less corrective EQ to accomplish what I want to hear. Let me rephrase that... I'm finding that when I adjust EQ, it appears to be far more effective with much smaller increments than the amounts I used to have to use to achieve the same result(s) - which I've since found out were inaccurate results.

Diffusion

I've yet to install any, as of this writing. Space has suggested reading material for me, and Andre was incredibly generous and sent me study material. I've decided that I'm not going to add any diffusion until I study more on the subject.

Absorption vs Reflective

As of this writing, the ratios of absorption to reflective surface(s) are about even to each other. I didn't really plan it that way, but so far this is the way it has worked out. While I have broadband and bass treatment, I also have hardwood flooring and untreated areas of walls and ceilings.

Recording

While my intention was to create an environment that was more accurate for mixing, I've had the chance since to record several vocal tracks, and the results are incredible. The vocals aren't hyped in any way, there's nothing there that jumps out to the untrained ear, but what I'm hearing is a much greater sense of "natural" tone, and the vocal tracks are much easier to sculpt, and require far less tonal sculpting.
I thought at first that perhaps it might be a kind of "placebo effect" - a power of suggestion - assuming that these tracks would automatically sound better because of the treatment - but it really is there.
It's not my imagination.
I've gone back and listened to vocal tracks I recorded in the past and there's a substantial difference to the way they sound. The older tracks sound "hollow" in comparison.
I need to mention that I listened to these vocal tracks outside of my mix space... I took a collection of old and new vocal tracks and played them back in my car, and the newer tracks sound far more natural compared to the older ones that were recorded before I treated the room.

Further Treatment

I'm not really sure at this point. I'm going to cease any further treatment until I have put some time into studying. For all I know, I may have too much treatment in place... I'm not saying I do, I'm saying that at this juncture, I don't know. Andre has sent me some priceless study materials, and until I dig into this material, I'm putting a temporary hold on any further steps. I want to know that any further treatment I add is genuinely needed, and I want to know the whys and the hows before I just blindly throw up more OC, Roxul, or Diffusion. There's no point in adding anything further until I know why I should be adding it.

Special Thanks

I've got a long way to go and much to learn, and I don't know if I'm done with my project yet; time and lots of studying will tell.
I'd like to thank everyone who took interest in my project... but especially to Space and Andre, Your advice and assistance was priceless. Sincere thanks to both of you for taking the time to help.
You directed me down the right paths and helped me to find many of the answers on my own, and this was important.
We can all be told what to do, step by step... but ...it's a lazy approach, and one in which we don't retain knowledge. Discovering and learning things on our own is the only way to truly retain the knowledge.
Thank you both for giving me the road maps from which I could do this correctly. :)

d./

Good on ya' D!!

Welcome to the final preparation for the wormhole of acoustic knowledge and an accurate environment. (The rest of the world generally refers to it as "insanity".)

I've been busier than a kat in a litterbox and have only had time to watch from the sidelines, but it's great to see someone else get that "eureka" moment! Congrats!!!

A good environment trumps all the damn hardware simulators, plug-ins, samplers and synthetic digital whizmadiddle you can stack on a hard drive.

Most everyone has the 3 or 4 "perfect" sessions in their career... e.g., needing little to zero processing after the recording process to achieve an acceptable final mix product. I've had the joy and outrageous fortune of having had at least 3 or 4 per YEAR here... and why I hammer on folks to get it right at the beginning... it's so much more enjoyable, ain't it?!?

Rock on!!!

Only one problem though...

Pix or it didn't happen. ;)

Okay... so here's my next situation...

After further research, including Ethan Winer's site, the material that Andre sent me, reading back through Space's posts, and various other accurate resources of info, I believe that I need further low-end treatment.

As I was looking at the room yesterday, I realized that I have been ignoring 4 major corners... and these are the corners on every wall -where the walls meets the ceiling. Because treating corners is one of the issues that I have learned as being fundamental, I'm thinking about fabricating traps that run the entire span of where all the walls meet the ceiling.

I have two trap frames, already built, that I saved from my old control room when I had a commercial facility. The frames are 10' long, 4"deep, and 12" wide, covered with an acoustically transparent fabric. They are currently empty.

My thought is to fill these with Roxul (I'm out of 703, and have an entire bale of 3" batts of Roxul left) and mount them with a 4 inch space between the Roxul and the boundary (ceiling) to extend the efficiency of the treatment. , I was thinking that it would be best to mount these to the ceiling, with the fabric covered side pointed down - towards the floor - as opposed to mounting it to the wall with the fabric covered side facing out and into the room. My reasoning for this is that I currently have quite a bit of broadband treatment mounted to the walls already, pointed in and towards the room, and I'm a little concerned that in ignoring these other corners mentioned, that I may not be treating the areas that perhaps need it the most...however, money is starting to get a bit tight, so I'm looking at the most efficient methods as well, and attempting to use materials I already have.

I have a suspicion that may or may not be valid - and that is that treating the span of the wall/ceiling that I currently face in the mix position, and which is closest to me in distance, is going to be important. Also, the wall behind me, and its corner at the ceiling, would seem to me to be the next most important area of treatment.

3 questions:

1. Does the above description seem to be a logical form of treatment?

2. Should I instead consider treatment measures of these corners by using a form of polycylindrical/half-circle shell that would cover the corners?

3. Either way, is it possible that I can accomplish sufficient trapping and attenuation of low end frequencies by treating only two of the wall/ceiling corner spans? Or, will it be necessary to treat all the areas where the walls meet the ceiling?

Apologies in advance if this appears to be a no-brainer for our resident experts... I really did go through quite a bit of reading material last night and this morning, trying to find the answer(s) on my own, and I wasn't able to come up with any answer pertaining to this particular situation...

Thoughts?

It's pretty simple actually, when it comes to Diffusion vs Absorption...

What do your waterfalls show?? How much ring are you gettin'?

The more LF ringing, indicates need for more absorption. If you're weak in the low mids, etc... diffusion is the easy answer.

Now, how much of what is the rocket surgery, but like any surgeon, you need to look at the problem to diagnose the surgical procedure.

Donny
first don't pay attention to anything the hot dog guy has to say. his only motivation is to sell room treatments. he has made some very outrageous claims in the past and i personally think he is full of sh*t. he does manufacture some products that work well but so do a lot of others. really they are just narrow band absorbers and they are nothing that you can't build yourself. i think they are ugly as well. his idea is to cover the whole room with them. echhh! this is from a guy to has said right here that a Mackie mixer is as good as a large format console or boutique mic pres ... what a maroon!

you're making a mountain out of a mole hill. i am far from an expert but i have done many rooms. this is a fix all approach and not scientific at all but any rectangular can be made better with a few simple steps. bass trap all four corners with superchunks. they will serve as broadband bass traps which in a dimensionally challenged room is what you want.

place absorption on the front wall and the side walls. i like to cover the front wall as much as possible but that may be overkill so i would say "season to taste" in your case. the side walls should get no more than necessary to tame errant reflection. the goal is not to absorb everything but to eliminate stray reflections. use the mirror on the wall trick . everywhere you can see reflections of the monitors place treatment. do pay attention to the trihedral corners.

last diffuse the rear wall. lot of ideas to do this ranging from bookcases to custom builds ... you need to decide if something works or not. i tend to lean to the 7 well types myself.

if all that doesn't do it for you then it's time to call in the pros for a consultation ...

Now this is a good idea... minimal weight, minimal framing... easy enough for even my carpentry-challenged mind to grasp.

"...everywhere you can see reflections of the monitors place treatment. .."

I've done this, in the beginning stages of the project.

"last diffuse the rear wall. lot of ideas to do this ranging from bookcases to custom builds ... you need to decide if something works or not."

I guess I've been holding off on this because I don't know enough about it - diffusion in general. I mean, I know what it's supposed to do, I'm just not sure how it pertains to my room, and I've heard stories of how misplaced diffusion can result in actual comb filtering in the room. I have an RPG type "skyline" diffusor that I made from plans I downloaded from the BBC. It's all finished... I just haven't mounted it yet, because it's pretty heavy, and I want to be sure that it will be of actual benefit. I've been reading past posts by Space, as well as through some reading material that Andre was kind enough to send me, and over the past few days I'm trying to focus on the subject of diffusion. I guess I'd just kinda like to know what to expect before I put the thing up, which will involve some pretty hefty anchors and screws. Actually, I've come to the point where I'd like to know about anything I am thinking about installing. I don't wanna be one of those guys who just starts randomly throwing stuff up on the walls and ceiling without knowing first what the result will be ( and I'm not saying that this is what you are saying to do... I'm saying I want to know about the treatments before I decide to use them. :)

And, if diffusion is simply nothing much other than an erratic surface, well, with all the erratic surfaces I already have - things like chairs, shelves, etc., again, I'm not sure I actually need the skyline BBC diffuser I built.

Thanks Kurt.

I use RealTraps (bass traps), they work for me and look great! Way better than open fiber that leaches into my breathing. Sonic Waves move fiber, and that isn't something I take lightly. So, think about your health first and foremost. People using open insulation and un approved products can keep it. Bookcases, a Lazyboy, stacks of records. Open back shelving... clouds (y)

I agree with Kurt on almost everything. I think there is so much overkill hype and BS in this industry. My room sounds great and it isn't rocket science. If I suck, its because I suck now. When you are able to mix a track that translates to your car, you got it man. The rest is getting to know your game, which has never stopped for me.

You can hear the bass accumulate real easy when you walk around. The mirror is a no brainer.
I really like the diffusion science. I have all sorts of diffusion already, but I want to build stuff that looks cool too so I am a visual guy because that also gets me work. Its fun impressing people too. ;)

Sounds like you have a great handle on all this and super advise from so many. Looking forward to hearing you smile when its all done and you are mixing away..

What baffles me,

When checking out studios and I see pics of mixing desks in a boxy room with bare walls and speakers in each corner. I don't know how they do it. And some of these are studios that claim to be Mastering. go figure.

i am not speaking of using open fiber absorbers. the chunks are fabricated from 702 or 704 (rigid fiberglass). if you are concerned about fibers cover them with Gulliford of Main fabric.

often what looks like a bare wall is really an acoustic panel. i bought some office partitions and took the feet off them and then screwed them to the wall through the metal frames. still looked like bare walls but really absorptive.

Donny .... what i am describing is a typical LEDE c/r. put the diffusors along the back wall and centered to the axis where the monitors are firing. diffusion remedies slap and flutter echos. i wouldn't think comb filtering would be a problem, in fact they do just the opposite. i have seen diffusers in vx booths used to eliminate comb filtering.

a poor mans spherical reflective slats are fence pickets. not exactly pretty, but you could sand them and make them pretty. thats what used to be up before i refinished this place, one of the studios i work at. i didnt make the reflective slats, a luthier did, but i did similar slat work in some other rooms in this facility, and i installed the ones pictured. the trick is the spacing between the slats, so your absorbing the bass you want, and reflecting the stuff you want. this was the 7th certified LEDE room in the US, designed by dan zellman in NYC, and Phil greene, engineer. notice fabric covers rigid insulation in the front/L/R dead side(s). theres anywhere from no space, to about 2-3 feet between the walls w/ the insulation mounted, and the fabric framed shell. the room was tuned during construction by putting the ceiling on hinges to get the proper angle, and by placing reflective pieces of ply wood on top of some of the insulation. the front wall was modified, to produce and extra 5 db below 60 or 80, to increase the efficiency of the bass drivers, by making them work less hard, and minimize distortion. i know ive been posting these pics a lot lately, just excited to see this thing nearing 'done'. as done as studios ever get, which seems like they are always morphing in some way. im gonna just start a thread of my builds. id be happy to answer any questions i can, and i can ask Phil anything about this setup i don't know. i also spoke w rod as well, so i ave some notes from him, some of which id have to pm to you. that mixer makes a killer desk to hold a track ball/qwrty keyoard. still working out the power supply issues, and some other kinks. its made me very weary of buying expensive things w out trying them, or having a tech go completely thru it. anyway, if there is anything you find interesting on diffusion, im all ears anyone :)

p.s ive been putting up some stained lattice to cover the seems, its lookin good. thats my boss in the pic, we were mixing some local death metal i recorded.

diggin' the Astatic D104 ..... what are you using it for?

Well, this is kinda embarrassing, I don't even know what the Astatic D104 is, lol, so I'm not using it for anything at the moment. Just looked it up, it's one of the mics, on the rack lol. I honestly think it's just for decoration at the moment. Were still wiring everything up. I'll have at try it out one of these days.

Do you have any experience w them?

Kurt Foster, post: 416251, member: 7836 wrote:

Donny .... what i am describing is a typical LEDE c/r. put the diffusors along the back wall and centered to the axis where the monitors are firing. diffusion remedies slap and flutter echos. i wouldn't think comb filtering would be a problem, in fact they do just the opposite. i have seen diffusers in vx booths used to eliminate comb filtering.

I understand what you ar saying, pal, and I do understand the concept of a LEDE mixing room... but, it's confusing to me how this would work with small bedroom "studios"... because unless the wall behind me is completely treated with diffusion, there's still going to be quite a bit of reflection back there to have to deal with, no?

I think that the LEDE concept would work great in a room that was sized big enough - to put some space between the mixing position and the wall behind it. And, I do understand that I can't ignore the wall behind my speakers - just because my speakers are firing away from that wall doesn't mean that reflective and standing waves aren't back there, especially in the room I'm in, which is pretty small compared to the standards of a professional studio. So again, I'm not sure that I can treat my room the same way professional large rooms are treated.

I'm not doubting that with enough money, I could get optimum results out of my room, for the room I'm in.... but... those optimum results are still never going to be of true professional standards, because of the size, dimension, and build.

In comparison to control rooms that were built from the ground up with acoustics in mind as the general factor, I think that my room is only ever going to get so good before I start seeing diminishing returns.

IMHO of course.

KMetal

Well, this is kinda embarrassing, I don't even know what the Astatic D104 is, lol, so I'm not using it for anything at the moment. Just looked it up, it's one of the mics, on the rack lol. I honestly think it's just for decoration at the moment. Were still wiring everything up. I'll have at try it out one of these days. Do you have any experience w them?

i had one back in the 70's. it was a power mic for CB /HAM radios. i haven't really ever heard of one being used for recording. might be good for talk back because you have to squeeze the handle to "key" them up. i ran the mic full volume (over modulating the radio) and with a 50 watt linear amp. it would make a huge "clunk" noise when i keyed up. i bought mine new i think it was about 100 bucks.

Donny;

it's confusing to me how this would work with small bedroom "studios"... because unless the wall behind me is completely treated with diffusion, there's still going to be quite a bit of reflection back there to have to deal with, no?

i bought a Leslie speaker from a studio in Sacramento once and later i learned it belonged to a very reputable professor who was almost "famous". i think his name was Dr Hong or something like that (i'll try to look it up.) anyway the studio had a very narrow / small c/r stuffed with a Euphonics digital console with the racks all in an adjacent machine room. on the rear wall of the c/r they had a diffuser system that looked a lot like that Acoustic Ramp system. so i wouldn't say that a small room doesn't need diffusion or at least benefit from it. they don't have to go wall to wall and remember they will be flanked with the chunks which will eat up at least 4 feet.

"i had one back in the 70's. it was a power mic for CB /HAM radios."

I remember those! If you had a CB you just had to have a power mic, that was the big thing.
"Hey y'all this is The Purple Pirate, KSQ-7788, Signing off."

Uhm... yeah. Okay...go ahead and laugh. For a brief period between '74 and '75 I was one of "those" people.

"on the rear wall of the c/r they had a diffuser system that looked a lot like that Acoustic Ramp system. so i wouldn't say that a small room doesn't need diffusion or at least benefit from it. they don't have to go wall to wall and remember they will be flanked with the chunks which will eat up at least 4 feet."

Well, that's the one thing I hadn't considered... I was mistakenly under the impression that with an LEDE room, the rear wall was diffusion only, no bass traps. I'm understanding better now what you are saying.

So, I'm assuming that this studio had a rep for putting out good sounding mixes?
What are your thoughts on the Ramp diffusion system? Have you ever mixed in a room with these in place?
One thing's for sure, they look to be a whole lot lighter in weight than the BBC 2D Diffuser I built.

And finally... whatever happened to the Leslie? LOL... Man, I want one so bad ... The double stack with the rotating speaker and horn. Although I honestly don't know where I'd put it.

Thanks Kurt. ;)

Well, that's the one thing I hadn't considered... I was mistakenly under the impression that with an LEDE room, the rear wall was diffusion only, no bass traps. I'm understanding better now what you are saying.

If you look at the rear wall of the pic, where the futon is, those things that stick out on either side are bass traps, about 4ft deep.

Also fwiw when I had my bedroom setup, about 7x11x12, it was pretty nasty around 78hz. I build two tuned resonators for the front corners, and took the door off of my closet on the rear wall, for some bass trapping. It could have used much much more. i built a bunch of 2x4 rokwool panels set up the RFZ ike you have except i useda moving blanket for a cloud (man what a diff a cloud makes, very overlooked by a lot of noobs) anyway i had a pretty dead rear wall w 2 pannels next to each other. and a dead front wall.

i didnt have one of tose pretty diffusiors you made but, the diff bbetween the untreated back wall and treted one was subjectivvely noticable. one idea i contemplated was putting diffusive things on the side walls behind my head, basically in between the side panel and rear wall, where the L/R walls where parallel, and bare. this might be something to consider, but again i dont have any scientific references for diffusion. from what i do know, is there is a good chance itd be better than bare walls, most likely, but how much better, and at what frequencies, i dunno.

if it were me and i couldn't find the answer, id probably just mount the diffusors in the potential areas, and listen, and test w REW. My bass test results, tested w/in .2 db of my math calculations for my room mode, w nothing more than a cheap interface and radio shack meter. At this point, not that you have the basicdirect reflections covered, ill echo max and say, its time to test, to find out your specific problem frequencies/areas.

superchunks, ill are broadband in nature, and will take some mids/highs out as well as some bass. so maybe some clever diffusion would help maintain life, so your not making snare drums sound like the 80s again w insane verb, unless thats our thing. or maybe adding some reflective strips to the super chunks could help. but really, i think most people would say its time to test your room and see what you've got, cuz otherwise its quite a bit of speculation on anything specific to your room and needs.

The results of the cloud that I installed were immediately apparent. Suddenly, I had definition and clarity that wasn't there before... and, the imaging was vastly improved as well.

Immediately after installing it ( I used 3" of OC 703 with a 3" air gap between the cloud and the ceiling) I was hearing things L,R, Center and Depth that I had never heard before.
It was astounding... and a great relief to know that what I had done made such a difference in a positive way.
I'm sure that the wall mounted broadband absorbers that I put up on either wall to my left and right helped a lot too, but that very first "lightbulb" moment was after installing the cloud.

In other related news, I'm ordering Rod's book today. I'm gonna wait on putting up any diffusion until I get a chance to read that part of his book.

I feel as if I need a better grasp of what it is, the best type of diffusion for my situation, and, last but not least, what it will do to my room, good... or bad.

I've been really good about avoiding "random" forms of treatment, and instead of believing everything I've read on the web, instead, I've stayed true to following known, accurate methods, up to this point in the project.
So, I haven't been "guessing" thus far - and I don't wanna start guessing now, either.

Money-wise, I can't afford to. I want to stick with accurate information, provided by an expert. ;)

d/

not to spoil it for u man, but unless there are significant changes in the 2nd edition of rods book, he doesnt touch much on diffusion, he only says what it is and does. due to size limitations in most home studios, he didn't feel it was worth getting deep into, and offered his approach, which was an RFZ w bass trapping (as much bas trapping as possible). so iif your looking for small room diffusion tips, they arent in there.

i know your trying to avoid the guesswork, so testing your room is gonna give the experts the info they need to interpret.

if i were gonna do trial and error, id mount the diffusor to a mic stand so i dont bang up the walls. but again, im not an expert, i do have a solid foundation of the basics though.

kmetal, post: 416317, member: 37533 wrote: not to spoil it for u man, but unless there are significant changes in the 2nd edition of rods book, he doesnt touch much on diffusion, he only says what it is and does. due to size limitations in most home studios, he didn't feel it was worth getting deep into, and offered his approach, which was an RFZ w bass trapping (as much bas trapping as possible). so iif your looking for small room diffusion tips, they arent in there.

i know your trying to avoid the guesswork, so testing your room is gonna give the experts the info they need to interpret.

if i were gonna do trial and error, id mount the diffusor to a mic stand so i dont bang up the walls. but again, im not an expert, i do have a solid foundation of the basics though.

Well...and this is only a guess... maybe he didn't feel the need to mention it for the exact same reason as to why I have been so hesitant about using it - because, as you mentioned, due to size limitations of most home studios in general, he didn't feel it was as important to cover as other methods. And this is exactly what my doubts have been based on all along regarding diffusion...because I too have a fairly small space, so perhaps diffusion isn't the best route for me, and instead I should focus on as much bass trapping as I can.

:)

My big question on this is still, would that diffusor be better than a bare flat wall? At what frequency? And is there a way ( that doesn't require an advanced math degree)to calculate this, based on the sequence of the diffusors pattern and the surrounding dimensions/materials? Or is it just kinda, put it up and see what it does?

Rods book some w some killer excel based calculators for the pertinent stuff covered in the book, TL value, cavity spaces resonant frequency, room modes, all really useful stuff. That book is worth it's weight in gold man, it's paid for itself over and over again, and the knowledge I got from that book allowed me to weasel my way into an engineering job at my studio :)

From all my research, and conversations, I think your on the right track about bass trapping. Are you planning on getting the free REW testing software? You don't even need to buy anything, just use your interface, and a mic. It has a calibration file for the radio shack spl meter, but I think pretty much any mic would work, and get ya in the ballpark.

i guess i'm going to have to dig out my copy of Everest and read up diffusion in small rooms.