Temporary "FAQ"- (was "Complete Section")

knightfly wrote:

Now that you mention it Rod, it doesn't seem to tally with accepted fact - you're right, sound control is NOT a "diode" situation - what made me think my comments might be true was the idea that "the best way to stop noise is not to generate it in the first place"

It's true that this is the best way......... but a wall is definately not a diode....

I know, you were expecting more of a fight there - it's your own damn fault for bein' so logical right off the bat.

Steve - I like you just too damned much to want to fight with you...... :lol: :lol: :lol:

Given the impossibility of satisfying the "one side only" rule with more than two rooms, I think I would tend to (in those cases) use NO RC in either side of wall sections that conflict, opting instead for double framed, offset stud, multi-layer construction with no two leaves made up the same way.

Well - if the wall isn't a diode - then this really isn't an issue....... who actually created this "rule" ?

I'm remembering comments by Eric Desart regarding low freq's and solid walls, and thinking that the improved low end blocking of an ALL solid (but separate framed and offset stud) 2-leaf partition might just average out better in response than one with RC - Eric's comments (and reading I've done) about PERCIEVED sound isolation being best with UNIFORM rejection would lead me to lean toward walls that favor low end TL slightly over STC.

Well, I would have to ponder that............. I remember - shortly after we completed Power Station - I went back for a walkthrough visit - sort of just checking to make certain we didn't have any problems (i would spot things that the client may not have) ........ and when i entered the lobby - i could hear a guitar playing in the main room......... i was a bit upset because i was thinking that something was wrong with door gasketing..... but when i opened the door it felt like the front of my face was going to be ripped off due to the volume. The guitar player was the sound tech hired by the company - he was a fantastic guitarist - who had actually turned down an offer from Ozzie Osborn to go on tour so he could take the tech job. I remember thinking how effective the wall was (along with the rest of the assembly) as i looked at the volume control on this monster Marshall Amp and saw that he had it completely pegged. So isn't there really a balancing act between the low frequencies and the highs....... and thus an attempt should be made to provide in the wall the best of both possible worlds. We know that we get a large benefit in STC (150hz - 4000khz) with the use of RC - shouldn't that be a part of the equation as well?

Man, that made me thirsty - anybody up for a beer? :? Sooo, whaddaya think Rod - am I back to "think like an Acoustician" yet? Steve

Beer sounds good - and you always think like an acoustician - however - the problem is - some of this just isn't logical - Keep up the good work my friend - these people have a great asset with you here. Rod

Hey, Rod - I'm always in favor of recieving kind words, but coming from someone with your background they're even more welcome. Your comments "So isn't there really a balancing act between the low frequencies and the highs....... and thus an attempt should be made to provide in the wall the best of both possible worlds. We know that we get a large benefit in STC (150hz - 4000khz) with the use of RC - shouldn't that be a part of the equation as well? " ... Are pretty much what I was trying to say before - If you consider that RC was sort of an "accident" that was later discovered to have benefit within the "speech" range, and that acousticians including Everest have been responsible for the statement I made regarding "uniformity of isolation", (which I probably should have referred to as "uniformity of Transmission Loss") - it just seems to me that, even though RC is used successfully, that a wall might be more easily balanced in TL throughout the REAL frequency spectrum of MUSIC, by NOT using the RC and just concentrating on two separate frames with DIFFERENT characteristics. Im not sure yet, but it seems like, since lows are much harder to block than highs, that if you slanted a wall's performance more toward the lows while at the same time using 3 different thicknesses of wallboard to control the upper end Coincidence Dips, and NOT gluing layers so that each could have its own NON-coincident resonance, you might just end up with a "super wall" that could keep those "power kick drums" as under control as the ever-popular "man singing with vise-grips attached to gonads" - Hey, this is fun - I'm already ready for another beer... Steve

Im not sure yet, but it seems like, since lows are much harder to block than highs, that if you slanted a wall's performance more toward the lows while at the same time using 3 different thicknesses of wallboard to control the upper end Coincidence Dips, and NOT gluing layers so that each could have its own NON-coincident resonance, you might just end up with a "super wall" that could keep those "power kick drums" as under control as the ever-popular "man singing with vise-grips attached to gonads" - Hey, this is fun - I'm already ready for another beer... Steve

Well - you are possibly correct - but - as we all know - ultimately - the only way to prove this one way or another - is to develope a design - analyze it the best that can be done mathematically - and then HAVE IT TESTED................ until then - i (personally) get tense suggesting anything to anyone.......... I am ready as well........... but then again - i am ALWAYS ready........... :P Rod[/quote]

" i (personally) get tense suggesting anything to anyone.......... " - Right there with ya - I'll be doing a LOT more research on my little "theories" before I deviate from tested designs - I try to remember to caution people that always ask "but what if I just..." that my answers are just (semi) educated guesses. So far, when people have followed my advice to completion they have been VERY satisfied with the results; just recently a guy in Austin finished a free-standing room following ALL my suggestions, and can't hear the drums at 10 feet away from the outside wall, all on a pretty restricted budget. He's happy; I'm ecstatic... Steve

knightfly wrote:

post your final choice in floor plans, I'd be glad to go thru the wall recomendations with you.

OK, here's my rendition of John's new awesome design: I am planning on using Rockwool and just found a local vendor for RC-1

Steve, I think you have a great natural talent for this - and that is the kind of feedback we always want to hear.......... :D :D :D Rod

Hey Rod - "I think you have a great natural talent for this " - Yeah, kind of like the "overnight success" that's only practiced his/her instrument and studied for 1/3 of their life-span... :roll: Still, I've always been a "troubleshooter" of sorts - the main thing I found to be different when getting into acoustics after years in the electronics field wasn't so much a change in mindset, as it was a change in "rules of logic" - the more familiar I get with the correct set of rules, the easier it is to apply them to a given situation. The main difficulty I find in doing this by "remote control", is the LACK of control - it's difficult to get people to give adequate info to solve a problem, when if they KNEW enough to include all the right information they wouldn't NEED us. Case in point - more often than not, when people new to the acoustics field give me room dimensions, at least 9 times out of 10 they only mention TWO. I can always tell when someone's done a fair amount of research before asking questions - it takes at least 4 less posts to get to a point where I can answer their original questions with some degree of confidence... Being in the field of industrial instrumentation, I get into a pretty varied range of technical fields, one of which is high vacuum arc melting - we have a saying about vacuum that could easily be stolen for Acoustics/sound proofing - "We Strive For Nothing" :wink: Gotta run for now, several questions left and I'm trying to finish up my small network redo; one DSL modem, one router/firewall, one switched hub, one print server, 3 printers, scanner, card reader, 2 XP machines and one 98se machine (so far) - almost there... Steve

Carl, at the risk of frustrating your efforts even more - You've GOT to be KIDDING with that floor plan, right? Seriously, the shapes are fine, but having to go through FOUR DOORS to get stuff into the main tracking room, and only ONE of those is double wide? Don't take offense at my comments, please - We've ALL been there, changing, moving, re-drawing, etc, finally hitting on the "perfect" setup, only to discover that we forgot to leave room for speakers, or a mic locker, etc - I would feel really bad if I let you build this plan without pointing these things out, especially if you're going to do ANY commercial work. It might be OK for a one-person, private project studio, but NOT for a working, for-hire facility. If I'm missing some bit of information here, please let me know - I REALLY want you to be happy with your results... Steve

John did the layout for me, all I have change is added the mic locker on to the right side of the sound lock. Believe me, if I had the room I would have seperate access to it from were the office is currently. I have taped it out on the floor in the room and my parter and I are comfortable with it. THe double door are the entry to the space so I can not change them. I am thinking of making the doors into the rooms 4 foot.

Personally, I would mirror the design top to bottom, and then live with the 2nd iso booth being a airlock entry/lobby. That way the entry with the double doors would lead almost directly to the live room. Just one man's opinion.............. Rod (flipping the layout would be easy - no need to even redraw the plans..... we used to build mirrored buildings all the time with just the original drawings - although - maybe being dyslexic helped a wee bit as well...........)

I had it that way originally. The line one bellow is my original idea I sent to John and the color image is John's design. Part of the problem is the damn pillar that's located in the sound lock. Wish I didn't have to deal with it.

Man, turn yer back for 15 minutes and they write a book... :evil: ... Oh well - Carl, that black thing is a pillar? Crap... Well, if you're comfy with your tape "walk-thru", that's the main thing for now. Widening the doors would probably be a good thing. I put 4 foot doors in my first studio, and it was probably the ONLY smart thing I did. As tied up as things are getting for me, I'd appreciate it if you could review a couple of the threads here (mainly the "complete section" one, and lay out what YOU think each wall section should be - then I can hopefully get caught up and make suggestions for any CHANGES, and why - the board is getting too popular for me to have enough time to do everything from scratch on a case-by-case basis, sorry... Steve

knightfly wrote:

lay out what YOU think each wall section should be

What do you mean? Like how I figured to create the walls? If that's it I was going to make them: 2x4 metal stud with rockwool > vinyl barrier (still looking for something cheaper but just as good as the Auralexpesive Sheet Block) > Philips/Dietrich RC-1 > 5/8" Firecheck Sheetrock > Homasote > 1/2" sheetrock > primer and paint. Floors (concrete base): neopren pucks w/ wood 2x6 and rockwool > vinyl barrier > 3/4' T&G OSB > 5/8" MDF > flooring (maple in live room, carpet in vocal booth, carpet and laminate flooring in control room)

Here I go adding to your confusion. I used in a previous design (1998) 1/8" Neoprene Sheet rubber in place of the Auralex Vinyl. I Personally think that if you just triple layer your control room/live room walls with Drywall you will just fine. I did that for my spot and am Quite happy with the sound deadening I have achieved. Bryan Giles Another Alternative is GAF Tri-Ply Roofing Roll. it is 37.00 a roll (40" x 30' long) Just as effective if you ask me. :) Finally I know someone has had to told you this or you read it elsewhere. That vinyl sheet needs to be placed between sheets of drywall to be most effective. On the floor and on the walls

giles117 wrote:

GAF Tri-Ply Roofing Roll. it is 37.00 a roll (40" x 30' long)

Yeah, I saw that on a back post and found some local vendors. But I can't find any good specs for it to know which type to buy. What are you using? All the Tri-Ply I saw listed was some asphalt thing. If I know what model number or thickness to get I would go that way. Or at least I can cover the existing walls with it to isolate the shell from my rooms I am building since some of my neighbor there are loud musicians too!

Hmm didn't realize there were multiple brands. I Used the rolls that Home Depot Carries. The Product is about 1/8 to 1/4" Thick. Wish I knew a model number . Don't remember there being one on the package. Just Tri-Ply was all that was listed. and the price being about $37.00 a roll. Has a smooth surface on one side and a honeycomb like surface on the other side. Bryan Giles

Here's the only spec sheet I could find, check out page 2: http://www.gaf.com/Content/Documents/50034.pdf What is the stock number for Home Depot, I will run out and get some from there ASAP!!!

Carl, you are making it tuff on me. The stuff I used is on a roll. It is not felt, it actually looks like rubber. The physical description I gave you is the best I can do. Here is a pic of what it may look like on the surcafe. <img src="http://www.johnlsayers.com/Studio/Images/Giles/LR_Floor_Mat.jpg" /img> That is the smooth srface, like I said the other surface is kind of a raised checkered (think honeycomb) Surface. It might be the #75. It is very heavy. Bryan Giles I'll Check it after church today and let you know what the part #, etc.. is

Sorry to be tuff on you. I just want to make sure I get the right stuff. My local Home Depot didn't have it and the guy tried selling me some other tar membrane stuff. I will just go to the local vendors that I know carry it. Thanks so much for the help and pic, I'll print it and take it in to make sure it's the same stuff. Man, I want to get this place built!

Carl, what's poppin. Had a Play to mix yesterday so I got in very late. Anyway the Correct stuff is GAF Tri-Ply TP4. Bryan Giles

COOL! Thanks so much.

Thought I'd ressurect this thread rather than write everything twice, had a Q from Fitz over on HR about ceilings and hadn't noticed much on that area in this thread - Keep in mind that (hopefully) our minds are not stagnant pools of amorphous gelatin with no noticeable shifts in patterns, shapes or awareness, so a couple of things I bring up here may slightly contradict earlier statements - don't panic, nothing major, just means I'm not dead yet (rumors have been maliciously exaggerated) :? Oh, yeah, ceilings... Here is part of Rick's post from HR (sorry Rick, getting tired of spewing out the same things in multiple places and wanted to make sure this got included in this particular thread, since it's fast becoming the "FAQ" I've yet to write... "Say, on CEILINGS, with 3 layers of Gypbd, would you fasten the first layer with minimal screws, as the next layers screws would also help fasten the previous layers? Alternating joints? Caulk each layers joints? How bout RC, will it hold the weight of 3 layers? Seems like the weight would negate the vibration capability of the RC flange, by pulling down on it. Would you float the ceiling gypbd panels between walls, or hang the ceiling gypbd first, so the wall gypbd helps supports the ceiling panels at the wall/ceiling intersection, like normal construction? Normal construction uses no blkng between joists at the wall intersection perpendicular to the joists. How about studio joists? Do you block them?" In order - On a first layer, it would be tempting to use fewer screws (all of this next is assuming you're using RC) but if you do, there's a possibility that the first layer could sag between screws, leaving a gap that would be hard to "suck up" with the screws for the second layer. Plus, because we ARE using RC, there's almost no reason NOT to use as many screws as it takes to get good holding. Remember, this is a ceiling (gravity, pain, etc.) Alternating joints and full caulking are a given ANYWHERE - RC and weight - Same as a car's springs - if you were designing a car the size of a Cadillac but only had springs for a Volkswagen, you'd have to use MORE springs, right? Same with RC - What you're trying for is a correct spring RATE, so if you want three FULL thickness layers on RC that's designed for TWO, put the RC on closer spacing to compensate. The Dietrich RC Deluxe, for example, will hold two full layers no problem. If you want three, cut the spacing down from 24" to 16" centers and you're good to go. If you were to use TWO layers of 5/8" rock with a thinner, 1/4" or 3/8" center layer (about the same performance as using sheet blok between two 5/8" but MUCH cheaper) then I'd split the difference and use 20" centers for the RC. Floating ceiling layers between walls - For most situations, this would be my first choice. Gives more vibration isolation between walls and ceiling. There are so many scenarios here, depending on what is being built where and in what order, that it's nearly impossible to describe each situation and prescribe for it. Remember, the goal (whether we achieve it or not) is TWO mass centers separated by ONE air space, in any direction you want to look (floor, ceiling, walls, doors, windows...) Blocking between ceiling joists, where possible, should be done as a continuous part of the OUTER leaf of the ceiling, which (usually) will include the above floor's subfloor mass. This blocking should be fortified with a couple layers of gypsum and sealed. Where walls that are parallel to ceiling joists meet the ceiling, an extra joist can be added to line up with the outer wall leaf. This should also have a couple layers of wallboard added because wood isn't as good for isolation as gypsum. I hope this answers some questions - here's an example, to clarify -

And here's an example of how to achieve part of the goal - Note the new drawing, this is just one way to achieve isolation of framing to avoid flanking thru wall into ceiling frame -

With a detail of the DIY sway bracket -

Hey Steve, I've just gotten into this whole building studios thing quite recently. I've already learnt a fair amount after reading what you and a lot of other people have been saying here, and it's helped me quite a bit. Anyways, I'd like to ask if you could help me by giving me some tips on soundproofing a room for band practices and basic recordings. My building has 6 flats in it, all attached side by side. Each apartment has 3 floors, and each apartment is separated by a wall. The top floor has 2 bedrooms and a bathroom, middle floor has a lounge, kitchen and a bathroom and the bottom floor a a spare room and a garage. Now I'd like to convert the bottom floor spare room into a sound proof room. The walls are concrete and 24 cm thick, as is the ceiling. I want to build a wall to close off the spare room downstairs and need some advice on that. The width of the room is 4m and length is 5m. I'd also like to know what I must then add to the rest of the walls inside the room to keep the noise to a minimum. There's also a window, and I would like to seal it off, how? How to I attach the RC to the wall and the dry wall/gypsum and how many layers should I use? I'm a bit confused, but what are the differences between gypsum and drywall? Or is it the same thing? What would you reccomend? What exaclty is rockwool? I read around but didn't find any good explanations, maybe I just missed them. What should I use for the ceiling? We only have to worry about the 2 walls already there and the third one I want to build, because the one at the end of the room is 3/4 underground. How this works is you enter the house via the middle floor, and to get to the back garden, there is a slanted drive way on the side of the flats. So the ground level in front of the house is high than the back, and thats why the room is 3/4 below the ground from the front. The room is however level. I've got the feeling I've just written the biggest load of crap and you won't understand, but I hope you do. Please let me know if you can offer me any advice and if you understand what I wrote. Rafal