Old 08-15-2007, 12:43 PM   #1
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Default Acoustical Science/Philosophy Showdown

This is a spinoff from JBM's "what would you do thread"

http://www.cockos.com/forum/showthread.php?t=11718

For most recordists, the science of room acoustics ( ESPECIALLY small room acoustics) is very confusing

NAY, downright FRIGHTENING!!!

All sorts of conflicting advice, that can make even audiophile craziness look tame in comparison

We need help here!

State your case please:

Your weapons will be Science and Evidence

One time only anectdotes are NOT evidence

An Ad Hominem Attack is not an argument, argue the science and claims involved NOT the person

Watch out for Post-hoc ergo propter hoc - eating ice cream does NOT make the sun hotter, be sure the result you claim is actually caused by the acoustic treatment in question.

Watch the Argument from Authority/ Appeal to Popularity - Just because Brittney Spears sells more albums than Black Sabbath does not necessarily mean Brittney Spears is BETTER than black Sabbath. Your Science should be strong enough to stand or fall on its own, without invoking client names or acoustical deities. Provide examples if you wish, but remember the one time anectdote rule, if your claim seems to violate Occam's Razor


HAVE AT IT!!!!
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Old 08-15-2007, 02:11 PM   #2
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I guess Ill kick this off...

703 vs 705. There is a claim that one is more/less effective than another.

What exactly does "more effective" mean. Sounds rather nebulous. One may be more effective for laying on when floating down the colorado river while the other might fly further given an identical toss. Perhaps some quantifiable terms would be better

Under WHAT circumstances would I want to use 703 and what circumstances 705?
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Old 09-02-2007, 06:21 PM   #3
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Default optimum solution

Okey pipelineaudio. Occam's Razor my favourite tool. Also JBM pleasant to me . I understand that he wants and I offer the optimum solution for home recording.
Jason, hi! If you really necessary to do record in a small room, you can have only one medicine is the glass wool.

http://www.ecophon-us.com/templates/...____85032.aspx

For example I use Isover Akusto POP (60 x 120 x 1,5cm).
You should paste glasswool panels three walls of a room completely. Also it is necessary to hang up curtains from a thick fabric on the fourth wall and a windows. You can change acoustics of a room moving a curtain. It can be made for one day. Also is possible to make from glass wool bass traps and to place them in corners of a room. Finally kills acoustics of a room glass wool on a ceiling. This all.
Following theme - noise of a computer. It is absolutely simple:

http: // www.arctic-cooling.com/pc_case1.php

Separate theme - confidential parameters of microphones.

Monitors also an intimate theme and I shall refrain from advice (good monitors at Loser). Is necessary to find the distance of focusing sound of monitors. For example your model of monitors should be located three times further from you.

For mix an ideal variant: Sennheiser HD 600. For recording: Beyerdynamic DT770. Also it is possible to use AKG K 44 (55) for all.
And chairs should not creak

These are universal recipes for small universal studios. It is not necessary to spend money and time for greater if it is not business.

It is my creative laboratory:

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Old 09-02-2007, 06:45 PM   #4
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thank you for this thread. I will be watching especially when i have money to put down on treatment.
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Old 09-11-2007, 07:36 AM   #5
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Hmm.. I dont have any money or will to treat my room so what I do is close micing on a spot where the computer noise is really low and unnoticeable. By the way, the only times I use a mic is to record acoustic guitar and vocals, the rest is plugged straight to the mixer so I dont mind a little less than perfect conditions.
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Old 11-15-2007, 10:16 PM   #6
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I guess Ill kick this off...

703 vs 705. There is a claim that one is more/less effective than another.

What exactly does "more effective" mean. Sounds rather nebulous. One may be more effective for laying on when floating down the colorado river while the other might fly further given an identical toss. Perhaps some quantifiable terms would be better

Under WHAT circumstances would I want to use 703 and what circumstances 705?
Well from what I understand, 705 has more mass and therefore will absorb lower freqs than 703. It also costs alot more. So, to me, it would make sense to use 705 for bass traps (eg straddling the corners) and 703 for broadband absorbers (eg mounted on walls, early reflection points, etc.) but if you're eating ice cream and drinking beer 703 will absorb down to 15hz so it's a moot point
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Old 06-01-2008, 04:13 AM   #7
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Well from what I understand, 705 has more mass and therefore will absorb lower freqs than 703. It also costs alot more. So, to me, it would make sense to use 705 for bass traps (eg straddling the corners) and 703 for broadband absorbers (eg mounted on walls, early reflection points, etc.) but if you're eating ice cream and drinking beer 703 will absorb down to 15hz so it's a moot point
No, no, no, no, no ....


they both have about the same lowest useful frequencies, it's just that 705's absorption is slightly tilted towards IT's lower frquencies, whereas 703 is more neutral. Which one you use is determined by the sonic signature of the room. neither is better. there is also 701, which is less dense and thus skewed slightly towards the higher frequencies.

NONE of this stuff can be used for bass traps, no matter what you might read on some website put up by some idiot who read one book & now thinks he's an expert. (Or some company that just wants to sell you something and knows you'll flock like sheep to an inexpensive solution) I won't mention names, but the internet is chock full of these sites.

705 don't do shite below 125Hz, I don't care if it's mounted in a corner and 2' thick. Bass energy can only be dissipated by large Helmholtz chambers, or lots & lots of panel absorbers. (or maybe a giant pair of noise-canceling headphones- Hey that's an idea: Electronic room tuning based on phase-cancellation!)
(yes, I'm kidding.)
--------------------------------

As far as small rooms go: Sadly, there is no happy solution. Since there is no support for important low frequencies, and also because all boundaries are within the Haas window, your only recourse is to make the room as dead as possible. This is not a fun way to work, does not translate well to the real world, and will likely cause to you turn up the volume to the point you will start to lose your hearing. -But at least you can get an accurate read from your nearfields.

Just the way it is. It's like asking how to get a good drum sound with 8' ceilings. same answer: You do what you can, & have fun doing it if possible, but don't kid yourself that you'll ever have the same as a pro studio.
Understand the limitations & work with them as best you can.

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Old 06-01-2008, 05:55 AM   #8
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NONE of this stuff can be used for bass traps, no matter what you might read on some website put up by some idiot who read one book & now thinks he's an expert. (Or some company that just wants to sell you something and knows you'll flock like sheep to an inexpensive solution) I won't mention names, but the internet is chock full of these sites.
Ermm... people like John Sayers and Ethan Winer are perceived as experts in the industry, both with decades of experience in building and tuning studios both large and small. And both support the fact that you CAN build working basstraps with this stuff. Of course you can't expect THE SAME results from an inexpensive solution as you would get from a Pro-solution, but YOU CAN expect results nevertheless.

Well, forums are full of people that know close to nothing and/or have no real experience in the matter but present themselves as the ultimate guru on the matter at hand (in most cases on each and every subject that comes along on the forum, don't worry, I won't mention your name either).
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Old 11-24-2008, 03:10 PM   #9
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EDIT: If you want to skip the theory and jump to the $100 room treatment recipe, go to part VI, below.

This thread is drifting dangerously off the path of hard science, but here goes (and this is partly summarizing/clarifying stuff that has been posted above):

Small rooms* are inherently difficult to use as recording spaces. The central problem is *caused by* low-frequency standing waves, but the effects are heard throughout the frequency spectrum. This is a really, really important distinction to understand. In very unscientific terms, low-frequency standing waves cause stuff in the room, as recorded, to sound generally boxy, ringy, indistinct, muddy, "peaky," and uneven. Generally cheap and unprofessional-sounding. It is *NOT* merely a condition of "too much bass" nor "bass buildup in corners" nor any of these kinds of well-intentioned misunderstandings that seem to think of bass trapping as a low-shelf filter for the room (although they may be some of the symptoms). It is a spectrum-wide, phase- and frequency-dependent distortion that happens throughout the room, and to different frequencies in different places, but happens throughout the frequency spectrum.

FORTUNATELY, there are ways of dealing with these huge, universal, full-spectrum problems that are CHEAP, SIMPLE, and EXTREMELY NON-TECHNICAL. More later.

What happens when you make a sound in an enclosed space is that sound radiates from the source, hits the nearby surfaces, bounces off them, hits the next surface it encounters, bounces off of that, and so on, gradually diminishing in intensity as resistance from the air and materials dissipates some of the sound energy as heat energy (a phenomenon called "absorption," since it's like the air and materials are absorbing the sound). When the sound waveforms are of a physically short length compared to the size of the enclosed space, the bouncing around randomizes the direction and intensity of the reflected sound at any given point in the room, and the result is a rich, even wash of reflections that we hear as reverberation.

Imagine breaking a rack of billiards balls and you'll get the idea-- everything ends up randomly scattered around, slowing down at different rates and so on, even though they all burst out from the same place with approximately the same force. Now imagine that you hit one billiard ball a LOT harder than the others, like, you shot it out of a pool-ball gun. It bounces furiously around and around the table and settles into a pattern, making the same path around the table repeatedly until it runs out of steam. This billiard ball is not only going to create a path where it clears out the other balls by knocking them out of the way, it's also going to create higher concentrations of billiard balls in the parts of the table that are *not* in its way. So it's going to disrupt the beautifully random pattern of balls and create unnatural areas of density and emptiness.

Now imagine breaking a giant rack of balls on a HUGE billiard table, the size of a swimming pool. This time, even if you launched some balls with the pool-ball gun, the table is so big that they end up scattering and randomizing just like all the other balls. The table is too big for them to settle into the disruptive round-and-round "pattern." If you see where this is going, you're one step ahead of the game already.

To be continued...

*"small room" in this context means any room that is not big enough to diffuse the wavelengths you're working with. A suitable room size for piccolo will be different than a suitable room size for double-bass. The smallest dimension is the most important one, but the overall size and shape matters. As a rough rule of thumb, a room with the shortest dimension being about 15 feet/4.5 meters is probably usable for general recording work, making certain assumptions about isolating bass instruments and not recording a concert grand, etc. A room with any dimension smaller than 12 feet is probably going to be a problem in any realistic scenario, since you are getting into territory where acoustic guitars and lower male vocals are creating problems.

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Old 07-29-2010, 03:50 PM   #10
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Ermm... people like John Sayers and Ethan Winer are perceived as experts in the industry, both with decades of experience in building and tuning studios both large and small. And both support the fact that you CAN build working basstraps with this stuff. Of course you can't expect THE SAME results from an inexpensive solution as you would get from a Pro-solution, but YOU CAN expect results nevertheless.

Well, forums are full of people that know close to nothing and/or have no real experience in the matter but present themselves as the ultimate guru on the matter at hand (in most cases on each and every subject that comes along on the forum, don't worry, I won't mention your name either).
Just re-reding this thread now.

Ethan Winer is no expert, in fact is a total bumbling idiot. He never built a room in his life. He was a musician who read a book or two (didn't understand what he read) then decided to start selling ultra-cheap acoustic "treatments", and started a website. His website is a magical, mystical place, where the laws of physics cease to exist. I've actually corrected him on various threads several times in the past, because he was giving totally wrong advice, after which he changed his website info accordingly. I no longer waste my time.

I used to build rooms for a living, how about you? I've worked for major acoustical design firms. You?

Try actually reading the BBC books, or the Everest books, or actual sabine-absorbtion data from companies like Owens Corning.

But hey, it's your money. Do what you you want. There are a ton of companies that will gladly sell you a hunk of foam, and tell you it's a bass-absorber. They have websites, so it must be true!

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Old 09-11-2007, 08:14 AM   #11
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Originally Posted by pipelineaudio View Post
Your weapons will be Science and Evidence
Now, what fun would that be?

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Watch out for Post-hoc ergo propter hoc - eating ice cream does NOT make the sun hotter.
What???!! And I suppose that drinking beer doesn't either! I urge everyone to refrain from believing claims just because there's Latin in the vicinity! "After I hoc'd, therefor because of it" indeed! Enuff beer and I, the sun, moon and stars will all hoc!

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Watch the Argument from Authority/ Appeal to Popularity - Just because Brittney Spears sells more albums than Black Sabbath does not necessarily mean Brittney Spears is BETTER than black Sabbath.
Is there no end to this Infidel-ity? Did you not see her on the Music Awards shew? Let Black Sabbath match THAT!


Sorry, Pipe. Just one of those mornings...
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Old 09-12-2007, 08:34 AM   #12
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Good grief! I hope my bent sense of humor didn't kill the thread!

I'm afraid I'm also one of those "avoid the room whenever possible" types that close-mics everything that I don't send direct. Seems to work pretty well so far, but knowing a little more about room handling is definitely of interest.

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Old 11-16-2007, 12:20 AM   #13
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Well as to fiberglass.... I spose there are numbers that support use of the materials in certain areas:

http://rodssoundsolutions.com/files/OC_703-705.xls

That spreadsheet gives absorption coefficients across the frequency spectrum. Or you can read up on some of Ethan Winter's study of the material here (among other places):

http://www.ethanwiner.com/density/density.html

Personally I use both types

705 ACROSS corners:


703 on walls:


But there are many more aspects of using this treatment that matter quite a bit to its performance.

1. FRK or not? (back or no back)
2. In corner/On plane.
3. Space from wall
4. Total thickness.

But some of the most important..

Color of covering. I feel dark blue is the best for low frequency absorption. Orange is excellent for mids and low mids.

Proximity of a bender toy. The closer he is to a monitor, the less bad sound he will allow in your mixes.

In the end I just like to tell my clients to amaze themselves by walking up to them and speaking at them... its like a sound sponge!! cool!!!

As to rafting down the rio grande on one... (the colorado river is father for me). No way man... you want to get super itchy??? I'd use rockwool for this.

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Old 11-17-2007, 12:49 PM   #14
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Good thread, will be watching with interest as I'm having a new room added for the purpose tunage
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Old 11-19-2007, 10:20 PM   #15
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Small Room Acoustics .... there is lots of stuff to take care of reflections that wont break the bank... like couches, matresses, ect

here is a little ramble that might help

1
do some sound checks a find the spot in the room that sounds best... thats were the mic should be (usually).

2
make some recordings recordings without any room modifications.

3
Listen to your recording. (You should be familiar with the flavor that your recording device places on the sound)

4
Identify what kind of problems are present that are not assoicated with your recording device. what frequencies are too loud, ect.

5
Create your solution based on your problems. Here are a few tips to help you find a solution

research different kind of mics and the Hz response / uses associated with them

personally i'll use a cardioid dynamic ( directional ) for the close up , and try to aim it at the rooms sweet spot... and i'll use a condenser for room ambience. you could place it in the room next door or whatever.. experiment a little with that

some of the greatest (professional) music i've heard was recorded on one mic in the center of the room (speedy west and jimmy bryant)

definitly walk around the house while the music is playing and try to find a sweet spot.

Lower freqs are stronger towards towards the floor, and gain momentum there. They also gain momentum in corners. you could spend alot of money on diffusers, or you could place a full sized couch in the corner (with one arm rest on the ground and the other facing the ceiling).

you might be playing too loud. the guitars / vocals in rock usually have to be cranked to 11 to compete with the drummer. try putting the drummer in another room and finding a place to mic (the drums) that sounds good.

matresses are pretty useful for diffusing reflections, plus they can add some sweet reverb (if the mic is close enough to it)

the reflections of the room might sound good if they are controlled. like instead of damping the whole room, you could create a damped chamber within the room using house hold items.

if your room has a closet or doorway you can place the mattress vertically in the doorway and suspend the mic on the other side of it (bout 4 to five feet off the ground). so the matress should be inbetween the mic and the soundset, with the mic in the other room. create some walls around the mic with blankets (floor to ceiling) to catch a few soft reflections. put some densely packed blankets on the floor immediately below the mic and then suspend another one (parallel with the floor) about a foot above the blanket mass. this will help absorb excess bass

TRACK Record!! You are on the reaper forum, so you probably have track recording capabilities. all you need is a set of headphones with a long cord to go from your computer to your musician. do one or two instruments at a time... start with the drummer and move on. that way you can use eq's, reverbs, ect to fix it up and address the needs of each instrument. I have a set of extreme isolation headphones, they are great for that, but they will run you about $99.99.

good luck!!
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Old 12-03-2007, 07:07 AM   #16
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This is a totally off-topic story, but I had to mention it after cAPS mentioned:

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Well as to fiberglass....
As to rafting down the rio grande on one... (the colorado river is father for me). No way man... you want to get super itchy???
LOL LOL.

Dude, when I was at uni, we were in the control room and a friend of mine was leaning on the wall rubbing his face on thinly-covered fibreglass. He was doing it for about 10-15 minutes! All of a sudden he said: "Uhhhhh, Paul...? Can I be excused? Only, I've been rubbing my face on this stuff here and I just realised it's fibreglass. I was thinking it felt quite nice for a while..."

LOL. His cheek was red and itchy and everything.
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Old 02-07-2008, 11:15 AM   #17
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Perhaps I went (a little bit) far with my control room, though I don't think so.

I took 2 of the corners away. Now there's a 2' piece at 45 degrees made of very thick plasterboard 1-4"! Home made dampening panels adorn the walls. The panels are made from good ol' rockwool bats coated with carpet interliner and fabric. There are a series of damper/reflectors hanging from the ceiling, but most importantly I vented the room into the attic space, which also has a damped cieling and one "wall" made of rockwall and chicken wire to hold it in place. That makes the attic space open to the elements at low frequencies, so the control room below is effectively ported.

My monitors are not that big (BM5a's) and as yet I don't have any subs. The room doesn't sound overdamped and is surprisingly accurate at quite low frequencies. I'm having to move soon. I'm not looking forward to it!

I think the best way to have faith in the mixdown environment is simply to do lots of them and play the results on as many different systems of vastly varying quality in as many diverse locations as possible, of course not forgetting to try every pair of headphones, etc. as possible. So far I'm pretty happy with my results and even the more discerning clients don't gripe at my efforts much. Then if I had no gripes and was totaly happy I'm pretty sure that I would have given up with trying to improve.
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Old 03-04-2008, 04:29 PM   #18
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Ahhh, here we go! I'm new to Reaper, but not new to room acoustics and setup. Now I can contribute something to the forum!

Quote:
Originally Posted by pipelineaudio View Post
I guess Ill kick this off...

703 vs 705. There is a claim that one is more/less effective than another.

What exactly does "more effective" mean. Sounds rather nebulous. One may be more effective for laying on when floating down the colorado river while the other might fly further given an identical toss. Perhaps some quantifiable terms would be better

Under WHAT circumstances would I want to use 703 and what circumstances 705?
'Effectiveness' of each material is related to frequency. 705 is denser than 703, which means it will be more effective at absorbing the stronger low frequencies (higher density of fibers=more obstruction of airflow).

Higher frequencies don't need as much density or mass to absorb, so the differences in materials don't matter at that point. In fact, once you get above 10 pounds per cubic foot density you can start reflecting some highs and mids instead of absorbing them. 703 is 3 lbs per cubic foot, 705 is 5 lbs per cubic foot.

So 705 will perform better as a bass trap due to it's higher density, but 703 will perform just as well for mids and highs.

How much difference there is in performance has been documented on Ethan's site (if memory serves), but many people have used 703 all around their rooms with good results. Making sure your panels are the right thickness and are positioned correctly is key; a 703 panel positioned correctly will outperform a 705 positioned wrong.

There are benefits for bass trapping in using 705, each person will have to decide what to use based on their budget. But there are alternatives to using Owens Corning stuff, any equivalent density rigid fiberglass or rock or mineral wool will perform similarly. I treated my room mostly with 8 lb per cubic foot density mineral wool from McMaster Carr. About $8 per 2'x4'x2" sheet, and they'll ship it anywhere in the states.

Quote:
Originally Posted by cAPSLOCK View Post
But there are many more aspects of using this treatment that matter quite a bit to its performance.

1. FRK or not? (back or no back)
2. In corner/On plane.
3. Space from wall
4. Total thickness.

cAPS
1. FRK or not?

There are tradeoffs to either. Having an FRK backing facing into the room can increase the effectiveness of the material at lower frequencies. This happens because as the air vibrates at the bass frequencies the paper or foil backing vibrates in sympathy and is then damped by the fiberglass. It absorbs a bit more energy this way as opposed to plain.

The tradeoff is that some mid and high frequencies will bounce off because they aren't strong enough to cause the backing to vibrate or to penetrate the paper or foil. This can work great for treating a practice space or live recording room where you want to control the bass but not make the room too dead. But for a critical listening room for mixing you want the room to be controlled and clean, not contributing any of it's own reverberation. So I wouldn't recommend using faced panels for a small mixing room.

2. In corner/on plane, 3. Space from wall

I hope I'm understanding this right, that you're referring to placing panels straddling the room corners versus placing them flush with the wall surface.

Placing strictly absorptive panels straddling room corners gives significantly better absorptive performance than on walls for a few reasons.

1) Bass frequencies build up in corners where surfaces meet. Simple addition, sound reflects off surfaces and bounces around, two or more surfaces meeting means more sound builds up there. So placing absorption at those points will do more for controlling sound, particularly critical bass frequencies, than placing them elsewhere. Wall/wall junctions, wall/ceiling junctions, wall/floor junctions, are all good places for bass traps. But if you can manage putting panels at wall/wall/ceiling junctions or wall/wall/floor junctions where three surfaces meet it's even better.

2) Placing absorptive panels at corners also gives you a large air space behind the panel while minimizing the loss of space in the room. A two foot wide panel placed straddling a corner will leave a large triangular air space behind it, which will help absorption.

Sound will pass through the panel and some of it will be absorbed, but the sound that isn't will bounce off the walls behind the panel and be absorbed again on the return trip. And the bigger the air space behind the panel, the lower the frequencies it will absorb (to a point), because the longer bass waves will have a bit of room to form and be absorbed a second time when they hit the panel.

Think of it like this: you bounce a ball off a wall. If you put a panel flush against the wall, the ball will just bounce off of it. It might not bounce as far because the panel is there.

But if you move the panel away from the wall and throw the ball behind the panel, it will bounce back and forth between them.

Now sound waves go through the panel and not behind it, but you get the idea. Once they're through, if they have room, they'll bounce off the wall and be absorbed again.

Lower frequencies have longer wavelengths, so the bigger the airspace the more effective the absorption at lower frequencies. Think of a bigger ball that needs more room.

Bass frequency wavelengths can be several feet long, but obviously putting a panel several feet off a wall is not very practical. But it's not really necessary because there is a lot of energy that can be absorbed at a quarter or even an eighth of the total wavelength.

But that's all talking about bass trapping. For mids and highs, which have shorter wavelengths that are easier to absorb, placing panels on walls will work fine, although spacing them off the wall by a couple inches or so will help them absorb to lower frequencies. More bass absorption is always a good thing.

4. Total thickness

For bass trapping in corners, four inches is effective but six is even better. Most people do four, and if they're positioned right they'll work nicely.

For wall mounted first reflection panels and general mid and high end absorption two inches works fine although spacing them from the wall a couple inches will help them work better to lower frequencies.


I really dove into all this stuff when I treated my room a few years back, so if there's anything I can do to help please just ask. I don't know everything by any means, but I'll be glad to share anything I do know. I actually co-moderated Ethan Winer's Acoustics forum for a few months a couple years ago at his request, and I learned everything I know about room treatment and acoustics from him.

I hope this helps!
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Old 01-31-2009, 06:00 AM   #19
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super-awesome-o thread!

Yep, your posts have explained the concepts here so clearly, it's really all making sense now. Great job, thankyou!
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Old 01-31-2009, 09:08 AM   #20
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Hey thanks for the info. I have a couple of questions...can anyone help?

1. When you go around your huose with a mic and a recorder...should it be any old mic? Or should you use the one you use for acuostic, the one you use for vocals...? Or do you just sing/ say "Here I am in the corner of the kitchen.....here I am in the middle of the TV room..."...then take this back to your daw and listen on your monitors? If you use any old mic...wouldn't you get basically inaccurate info?

2. Can you eliminate room issues by mixing at rather quiet levels?

thanks
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Old 01-31-2009, 02:11 PM   #21
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Hey thanks for the info. I have a couple of questions...can anyone help?

1. When you go around your huose with a mic and a recorder...should it be any old mic? Or should you use the one you use for acuostic, the one you use for vocals...? Or do you just sing/ say "Here I am in the corner of the kitchen.....here I am in the middle of the TV room..."...then take this back to your daw and listen on your monitors? If you use any old mic...wouldn't you get basically inaccurate info?

2. Can you eliminate room issues by mixing at rather quiet levels?

thanks
1. Sure, whatever. Different mics with different pickup patterns will pick up more or less of the room sound depending on how you hold the mic and so forth, but this is just ear-training, it's not an exact science. Spend another twelve minutes and try it with three different mics if you like.

Unless I miss my guess, the differences will not be so subtle that you need to get all precious about which mic best reveals the differences between the kitchen and the living room. I think it will be pretty obvious without too much thought or effort.

2. No, volume has nothing to do with it. At any volume, you CAN mitigate the room effects by listening closer to the speakers ("nearfield" monitoring), because the closer you get to the speakers, the more you increase the ratio of direct sound to reflected sound (like turning down the reverb), but it's still not going to solve the serious standing wave problems that practically all residential spaces have.
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Old 02-15-2010, 05:16 AM   #22
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... if your claim seems to violate Occam's Razor

...
Why do people say this silly line from a movie? Is it because it has the word "razor" in it? LOL!

Occam's Razor is at best a suggestion of causes not a law. Geez, computer software defects prove time and again, sometimes the simplest apparent causes are not the real ones, LOL!

"the scientific method, Occam's razor is not considered an irrefutable principle of logic, and certainly not a scientific result.[6][7][8][9]"

[6] Philosophy of Chemistry, Vol. 3, pp. 3-28, (1997).
[7] ^ a b c Alan Baker, Simplicity, Stanford Encyclopedia of Philosophy, (2004) http://plato.stanford.edu/entries/simplicity/
[8] ^ a b c d e f g Courtney A, Courtney M: Comments Regarding "On the Nature Of Science", Physics in Canada, Vol. 64, No. 3 (2008), p7-8.
# ^ a b c d e f Dieter Gernert, Ockham's Razor and Its Improper Use, Journal of Scientific Exploration, Vol. 21, No. 1, pp. 135-140, (2007).
[9] ^ a b c d Elliott Sober, Let’s Razor Occam’s Razor, p. 73-93, from Dudley Knowles (ed.) Explanation and Its Limits, Cambridge University Press (1994).
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Old 03-07-2010, 06:58 PM   #23
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Originally Posted by flmason View Post
Why do people say this silly line from a movie? Is it because it has the word "razor" in it? LOL!

Occam's Razor is at best a suggestion of causes not a law. Geez, computer software defects prove time and again, sometimes the simplest apparent causes are not the real ones, LOL!

"the scientific method, Occam's razor is not considered an irrefutable principle of logic, and certainly not a scientific result.[6][7][8][9]"

[6] Philosophy of Chemistry, Vol. 3, pp. 3-28, (1997).
[7] ^ a b c Alan Baker, Simplicity, Stanford Encyclopedia of Philosophy, (2004) http://plato.stanford.edu/entries/simplicity/
[8] ^ a b c d e f g Courtney A, Courtney M: Comments Regarding "On the Nature Of Science", Physics in Canada, Vol. 64, No. 3 (2008), p7-8.
# ^ a b c d e f Dieter Gernert, Ockham's Razor and Its Improper Use, Journal of Scientific Exploration, Vol. 21, No. 1, pp. 135-140, (2007).
[9] ^ a b c d Elliott Sober, Let’s Razor Occam’s Razor, p. 73-93, from Dudley Knowles (ed.) Explanation and Its Limits, Cambridge University Press (1994).
occam's razor is an heuristic - 'the simplest correct solution is the best one' the wikipedia article is pretty good http://en.wikipedia.org/wiki/Occam%27s_razor

but the thing to keep in mind is that Occam's razor is used to choose between competing correct accounts, not just competing accounts and is a kind of measure of utility rather than correctness(because it assumes equivalent correctness amongst the competing accounts)
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Old 03-07-2010, 10:23 PM   #24
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the anechoic chamber; is it the holy grail when all is said and done?
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Old 03-08-2010, 07:08 PM   #25
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the anechoic chamber; is it the holy grail when all is said and done?
No.

An anechoic chamber is an extraordinary unpleasant place to spend time in, and is certainly not the ideal place for either recording or monitoring.

The "holy grail", if there is one, is probably a space with at least two rooms: an ideal concert hall, with a big, natural, "blooming" full-frequency resonance, and a small, intimate, short-decay "listening room", like a large, idealized living room.
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Old 11-03-2017, 12:51 AM   #26
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One time only anectdotes are NOT evidence

HAVE AT IT!!!!
Just an amateurish experiment, not true science, no replication, nothing but anecdotal evidence...

But, I seek not to change the world, make money, convince others; I seek only a better recorded guitar sound, for myself given my unique setup and gear (i.e. cheap amateur-entry level stuff).

I was told that 'blankets' could not treat a room, so... I tried it anyway!

In this non-replicated experiment (N=1), I have this to report: The blankets improved the quality of the recorded guitar.

Here is my experimental 'treated room' / recording booth:



Results:

I noticed less background noise, less harshness, less 'robotic' metallic distortion/artifacts (note: cheap condenser microphone - blue yeti that I detest), and also less random spikes in the harmonics/overtones. Somehow, this experiment made me not want to toss the microphone in the garbage anymore...

Draw backs? It's hot in there!!! lol
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Old 02-26-2019, 09:23 PM   #27
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Default Sound control curtains?

My music room is 10 by 14 and I am treating it based on Yep's recomendations. Since I have things against most of the walls and corners I'm going to put 4 OC 703 panels on 3 way corners of the ceiling/walls, 1 more OC panel on a 2 way corner of the ceiling/wall, my 6th panel split in 1/2 placed on the early reflection points of the side walls.

My back wall is a wooden door to a hall way and sliding closet doors, these take up almost the entire width of the wall. Inside the closet is a file cabinet and music gear (i.e. no clothing).

I'm thinking the next think to treat is the back wall reflection. Would sound control curtains hanging off of the back wall in front of the closet be useful?

Something like:

https://smile.amazon.com/Moondream-S...-1-spons&psc=1

Last edited by fep; 02-26-2019 at 09:29 PM.
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