Craig - Please! Let's create a group dedicated to Acoustics...

[JingleJungle]

Hi Craig, hello group... I am currently redesigning my small post-production studio and I've been hunting all over for viable info on acoustics, building Hemholtz resonators, tube traps, etc. Whatever has been contributed to these forums is way too fragmented and it takes an awful lotta time to get it all together. Could you please enquiry with the powers-to-be and ask'em if this group could be created? I do believe that this topic is definitely up EQ's alley... Please? :) best wishes from Switzerland, Paul

[Philip OKeefe]

Jingle Jungle, I'll try to answer whatever I can as often as I can, but it's not a really simple subject, and without having specific drawings and knowing what the current structural materials, budget, noise attenuation and useage issues are, no one can give you any real in depth details. Each room is as individual as the needs of the client when it comes to acoustical design. IMO, while a forum of this nature would be nice to have, getting someone great to moderate it might be difficult. There's not all that many truely "great" acoustical designers out there, and the ones that DO exist make their living off their knowledge, and giving it away in abundance is sort of like shooting themselves in the foot. And besides, chances are that it wouldn't be a overly popular forum - most people only need those services a few times in the course of their careers. And while there might be some general interest in acoustical topics, I rather doubt that it would be extensive - which is unfortunate because a general understanding of acoustics and the propagation of sound is essential to a good engineer. But back to you... I recommend you get a copy of F Alton Everest's "Master Handbook of Acoustics". It might be available at your local library, or they can probably get it through a inter-library loan for you. That should be a good starting point for you - not too technical, but it covers the basics fairly well. Best of luck with your new room, Phil O'Keefe Sound Sanctuary Recording Riverside CA http://members.aol.com/ssanctuary/index.html pokeefe777@msn.com

[JingleJungle]

Pkefee...you must be living on your 'puter keyboard, man! THe reason I would like to see a list / group is because it *should* be a proper thing to do to pool member's various positive AND negative experiences in this field. Most of the semi-pro probably will be building up and improving our studios / rooms over time, and will face different issues each time. I shall definitely buy Everest's books, as a matter of my own personal education (I shall simply order them via Amazon, forget the local bookstores :mad: )but I *still* think that sharing experiences is an invaluable service to the whole music community. A musical hug from Switzerland, Paul

[halljams]

This is a topic i too would like to see get some discussion. Ok, maby it is quite complex and difficult to cover but, i know nothing about it, and would really enjoy reading some discussion on it here. I'm sorry Phil, but the idea that someone with a strong knowledge of a subject should keep it to themselves in order to preserve a place at the top is silly, and dare i say, immature. If i really wanted to be an expert on acoustics, i would be, and i would take as much of your or anyone elses work that i wanted to and you couldn't stop me. So there! lol That is not the case though, I just think it would be an educational topic to have floating around the forum, it is a pretty big part of this whole recording thing, and it gets very little attention, so lets talk about it. :D

[Philip OKeefe]

Okay guys, a couple of points: First of all, while I do the occasional design consultation job for local municipal agencies, churches and small studios, it's not the major part of my income. I personally feel that I have an OBLIGATION to share information with people in return "payment" for all of those who freely shared the same with me as I was getting started. I'm secure enough in my own abilities and client base, and the size of "pie" is large enough that I don't worry too much about competition. There's always room for more people in any industry - if they're good, and there will always be room for me in the industry as well - as long as I can do good work, charge fairly for it and treat my clients with respect and provide them excellent customer service... ...so what I was trying to say wasn't that *I* would be unwilling to share whatever acoustical knowledge I have, but rather that there might be concerns on the part of others who REALLY make their living at it. Why would, say, Chips Davis spend a few hours "doing the math" for you when he does that for a living? Okay, he could answer questions for you on "how to do the math", and I agree that this would be somewhat different. The people that hire Mr Davis are, for the most part, in a much different financial league and have different (and more demanding / exacting needs) than most of the home recordists that populate forums like this. But remember, Musicplayer has ALL SORTS of members - from rank newbies who have just purchased a used 4 track cassette all the way up to Grammy winners with platinum on the walls. I think if you check my "record" here, you'll find that I've been willing to offer opinions and advice on just about any subject where I felt I could knowledgeably contribute - including acoustical related questions. Anyone who really wants to be an "expert" on acoustics may get a "start" on a forum like this, but it's going to take them a considerable amount of study and effort to achieve that goal. But I do agree that a general forum concerning this subject would be nice - but again, I doubt that there is sufficient interest for Musicplayer to justify it. I'm willing to admit that I may very well be wrong on this... let's see how amny posts get placed here in support of it. Phil O'Keefe Sound Sanctuary Recording Riverside CA http://members.aol.com/ssanctuary/index.html pokeefe777@msn.com

[videoeditor1]

Hey there Phil, I'm backing you on this one pal. For a living, I do computer related stuff. Networks, IT security, etc. As a rule, I [b]never[/b] go on the PC related forums. I don't make my livihood common knowledge to the people in my apartment building, all my friends are aware on how much I'll extend my self to help them with their PC issues.... I tell them to call the toll free tech support for their service provider(s). In the past, I'd get apologetic calls from friends and the likes at midnite ebcause they couldn't load a CD or their modem isn't working..... Now, I find that some people I've dealt with do not understand nor appreciate the time, effort and expense it takes to be "current" with the stuff that I do. I'd much rather not deal with it. Having said that; music is my "first love". Even if I earned a living from music, I'd probably be just as judicious with the information I dispense. Most of the stuff I've learnt related to music and engineering has been fun & challenging. I'm more inclined to point people in a specific direction where they can experience the joy of discovery and understanding stuff, vs just crunching numbers and/or pulling solutions from memory and spitting out an answer. I [b]do[/b] think there are a great bunch of people on these forums. Occasionally, we get some "lazy" ones that just want a quick fix, those I avoid. I'm in the process of acoustically treating my facility. It's that area of audio where I feel least qualified. I can run the power, wire the studio, do the ventilation systems, the data storage / backup, but the acoustic treatment is when I'll whip out the checkbook. It would be nice if we had a guru or two, even if we did, I'd probably still get someone recognized or certified at it. NYC Drew

[halljams]

Jeeze , sorry Phil, i really meant all that in a light hearted way, i read it again and realize it didn't come across that way. I have tons of respect for you as an individual here on this forum, and am well aware that you are more than willing to share your knowlege with us and others. No need here for you to defend yourself. Cheers

[JingleJungle]

Phil (and NYC Drew)... don't get me wrong! I DO appreciate all the help you are providing to all the clueless, lazy, uncapable, desperate users out there. I'm one of the first that has received a lot of support from you, and have surely garnered a wealth of information from your other posts. Having said that, I do feel there's a difference when sharing tips, giving hints or suggestions to someone on how to fix a problem, vs. actually solving the whole problem and/or *materially* fixing it. If someone has the money to pay up for immediate consultancy, service and the physical execution of the job (i.e. the Platinum Grammy Artist) he should (I would) by every means do it. I do not expect him/her to then give away for free whatever has been paid for. However some amongst us do not have the luck to live in the Music Mecca - be it LA, Nashville or NY - and we gotta scrape together whatever kind of info comes our way...that's the *real* problem! In my personal case, the closest acoustics technician probably is 2 - 3 hours from where I live, they probably get paid at least $75/hr. plus travel expenses (150 miles or so). Moreover, at the end of the day I wouldn't have the guarantee they did a proper job (I'd rather make my own mistakes for that kinda money)!!! My 2 dbs' worth... Paul

[Steven Denike]

[quote]Originally posted by halljams: [b]i know nothing about itIf i really wanted to be an expert on acoustics, i would be, and i would take as much of your or anyone elses work that i wanted to and you couldn't stop me. So there! lol :D [/b][/quote] The reason you aren't an expert on acoustics is because it's SO WARM in Whitehorse that you can record outdoors all year round! Just a thought . . . Northern living allowance . . . having to use a blowtorch to loosen the lug nuts on your wheel before changing a tire . . . Gotta love it!

[gtrmac]

Ethan Winer has some good information on his website and some searches will get you a ton of resources about acoustics. I can tell you one thing I have found out about the subject over the years: it's an art. There are scientific principles involved but there are aesthetics also and when combined you can have some unpredictable results, sometimes not favorable. I've seen a few rooms which were designed by top firms pulled apart and "fixed". Taste and fashion have a part in this too. The best advice is to get an experienced professional to design your studio after you have selected one based on seeing and hearing some of his/her rooms.

[JingleJungle]

[quote] Northern living allowance . . . having to use a blowtorch to loosen the lug nuts on your wheel before changing a tire . . . [/quote] Northern allowance part II... Real estate prices are so low you can afford to rent spaces for a dime...or build an acoustically correct dream studio for a song & dance (even better if it goes platinum)! ;) [quote]There are scientific principles involved but there are aesthetics also and when combined you can have some unpredictable results, sometimes not favorable[/quote] I, for one, just need some good ole funky tips to get the room to sound properly - that's all... An example question would be: does a panel absorber or resonator still work properly if placed 10-20 inches behind a loaded library? What's the minimum distance between the sound source and an absorber? (whoops...that's 2 questions - sorry)... Paul

[Dogfur]

I'll vote yes for a catagory on this subject. I've really needed some advice fora couple of projects for a while. I think that an actual acoustic expert dispersing myths, sharing construction horror stories, etc... could prove very enlightening. I would certainly check in... Another $.02, Dogfur

[Philip OKeefe]

[quote]Originally posted by JingleJungle: [b] An example question would be: does a panel absorber or resonator still work properly if placed 10-20 inches behind a loaded library?[/b] Do you mean a "bookshelf unit? Several questions come into play here. First of all, what is the bookself made of, how thick is it and at what center frequency is the panel absorber designed for? Without taking all of these issue's answers into account, the basic answer is probably going to be "yes". Remember, bass frequencies are pretty much omnidirectional, have long wavelengths and pretty much "power through" all but the thickest and most massive of materials. Books and wood will provide SOME slight LF attenuation, but for the most part, they might as well not even be there as far as a 100 Hz wave is concerned. The initial question, before doing any design or acoustical "improvements" is to analyze where you're at now. Have you calculated how many Sabines of absorption you currently have in the room? Have you done axial, tangential and oblique modal analysis? Heck, have you even tried "shooting" the room with noise and an RTA or computer acoustics program to see what you're dealing with frequency wise? This isn't meant to sound condensending or rude... it's meant to be a few hints for further "keyword" searches here on Musicplayer and on the Internet and at your local library. :) Anyway, I got a bit off track. Where was I? Oh yes... At higher frequencies though, a bookcase, filled with a wide and random variety of various sized and thickness books makes for a very good budget diffuser. [b] What's the minimum distance between the sound source and an absorber? (whoops...that's 2 questions - sorry)...[/b] (in sotto - Montypythonesque voice) Sorry, you've used up your one question allowance for today. Please try again tomorrow. :D Again, it depends on frequency and type of "absorber". What specifically are we talking about here? Phil O'Keefe Sound Sanctuary Recording Riverside CA http://members.aol.com/ssanctuary/index.html email: pokeefe777@msn.com [/quote]

[videoeditor1]

Jingle, Ya know I got nothing but love for all my industrious peeps. :) Yeah, we outta fix it where a guy like you needs pointed in the right directions, like to get the ball rolling, a little "pre" production, so at least you'll have a clear pic of what's involved..etc. For the life of me, I can't remember WHY these forums were implemented, but some days it feels like we always get a guy or gal asking... "how do you get that R&B sound? What mic did you use? What outboard?" etc I'm in the process of treating my space (actually taking bids and the likes) so anything useful - I'll pass on to ya! NYC Drew

[JingleJungle]

Pokefee Well, thank you very much for your help.. Yes, I did do my math homework on room modes and I've got the resonant frequencies and harmonics *almost* worked out (the room is slightly irregular in shape, you see). Anyway, Brian (remember *that* MP film?): 1) the bookcase, bookshelf (call it whatever) does not have a back panel and will be placed about 1.5 ft from the rear wall...Yes I am aware of the omnidirectionality of bass frequencies but it's the absorber's mechanics and idiosyncrasies that I can't fully fathom at this stage. You may aware, for example, that depending on where the port is placed on a Helmholtz resonator a different formula should be used (just to complicate things further), ditto for the resonator's shape... 2) I would like to place a resonator or tube trap for the bass frequencies *behind* the console, between the mixer and the front wall (3 ft away). In effect it would be slightly behind the monitor stands. Given that it takes some distance to create the lo-freq wave, this placement may be totally useless and/or counterproductive. Ideas? NYC... thanx man, you're such a pro... With respect & thanx, Paul [stranded in an acoustical quagmire]

[halljams]

Well there, ya see, i'm learnin' shit already! Keep yappin you two! As for livin in the north, You guys might be thankful to have a good friend up here in a couple years. I'll gladly show you several uses for a blow torch. Not to mention where to fish, ride you bike and snow mobile. Well i might not show you where to fish....well, Unless a good conversation on acoustics is going to part of the afternoon. Cheers JH

[JingleJungle]

Halljams... I was just about forgetting... all those acoustic formulas work @about 71 degrees F. Now someone might try to work 'em out for you latitude & longitude, and definitely rework them for the polar temperatures of the nordic studios. BTW, what kind of HF damping effect does a snowstorm make? Is it dependent on the shape / size / humidity of the snowflake or more on the density of the snowfall? :) Paul (Sunny & balmy here in Lugano, Switzerland, despite the season)

[halljams]

[QUOTE]Originally posted by JingleJungle: [QB]Halljams... I was just about forgetting... all those acoustic formulas work @about 71 degrees F. My igloo is solar powered so that is only a problem on cloudy days. I try to use medium density snow for the side walls of my mixing room and softer fresh un-packed powdered squares wrapped in moose hide for the ceiling and back wall. The floor has taken me several years to get just right as i have had to layer several sheets of ice over the uneven ground of this godforsaken glacier which is constantly rumling and moving. Talk about a noise floor! As for tempature, yes, it is a factor but i have learned to compensate for the dry arctic air coupled with the cooler temps by comparing the whale and walrus sounds i so love to record, with some really good live bootleg Jimi Hendrix feedback recordings done at sea level that i got from this guy who went sledding past on some corporate getaway a few years ago. In exchange he took two of our women and one dog. None of whom were doing any good for the group at the time. Any other considerations?

[JingleJungle]

That's the way, brother... I'd give away [almost] anything for some good Hendrix bootlegs! Wail on Paul

[halljams]

[quote]Originally posted by JingleJungle: [b] Wail on [/b][/quote] Of coarse, you mean; Whale on.

[Philip OKeefe]

[quote]Originally posted by JingleJungle: [b] I would like to place a resonator or tube trap for the bass frequencies *behind* the console, between the mixer and the front wall (3 ft away). In effect it would be slightly behind the monitor stands. Given that it takes some distance to create the lo-freq wave, this placement may be totally useless and/or counterproductive. Ideas? [/b][/quote] I see no reason why you can't put it there, but again, you need to calculate how many Sabines of absorption you have already, and how much more you need, and at what frequencies, before you decide on what treatment. IMO, getting the bass traps into corners (especially trihedrial corners, where two walls and the floor or ceiling converge) is a good place to go if you have the room for them there. You might also want to consider a large bass trap behind the rear wall diffusers, so going behind the bookcase is also a good place to put some LF control. I'm really simplifying and generalizing here, because it's just too dang hard to give any hard and fast rules without knowing exactly what you're dealing with from viewing building plans, but think of where you'd put a subwoofer. It's not as critical as the placement of your mains or nearfields, because of the omnidirectionality of the frequencies involved. Most small rooms don't need to worry as much that they have "too much" LF absorption - most such rooms have way too little. But just throwing up tons of Hemholtz resonators, corner traps and panel resonators isn't going to even out the overall RT60 time of the room across the frequency spectrum - which is what you're after. Again, there's no substitute for "the math" and that's where I really can't help you. Phil O'Keefe Sound Sanctuary Recording Riverside CA http://members.aol.com/ssanctuary/index.html email: pokeefe777@msn.com