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 09-11-2007, 08:14 AM   #6
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Quote:
Originally Posted by pipelineaudio View Post
Your weapons will be Science and Evidence
Now, what fun would that be?

Quote:
Originally Posted by pipelineaudio View Post
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   #7
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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 11-15-2007, 10:16 PM   #8
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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?
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 11-16-2007, 12:20 AM   #9
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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   #10
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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   #11
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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   #12
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This is a totally off-topic story, but I had to mention it after cAPS mentioned:

Quote:
Originally Posted by cAPSLOCK View Post
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   #13
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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   #14
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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 06-01-2008, 04:13 AM   #15
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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   #16
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Quote:
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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   #17
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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.

Last edited by yep; 11-24-2008 at 09:15 PM.
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Old 11-24-2008, 04:20 PM   #18
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Causes and effects part II

To bring this back to sound, the problem with low frequencies is that the waveforms are much longer in terms of their cycle through positive and negative pressure. The low E on a bass guitar takes something like 33 feet to resolve in open air. If you have room dimensions less than 33 feet, especially if they are less than half of 33 feet, then that E note is not simply going to diffuse and dissolve into random room reverberation, but is instead going to settle into a fixed but haphazard path through the room, creating standing positive and negative pressure spots that are going to cause comb-filtering effects through the entire frequency spectrum. And it's not just one "snake" going through the room, because the bass amp is emitting sound pressure in all directions, and is playing other notes and harmonics of those notes that each finding their own patterns to settle into.

The net result is that you have have all sorts of effectively randomized acoustical peaks and valleys all over the room, and frequency response is different in every square foot, maybe even every inch. You're hearing a sharp ringing at 2kHz and overly-heavy bass while the guy right next to you is hearing scooped mids and papery highs. And the double cruelty is that the remarkable design of human hearing is such that your real perception is compensating for this, making the effect very hard for you to detect unless you are a practiced listener, but the mic is picking up all this ugliness just fine. So it perpetually sounds like your recordings just suck, even though it sounds groovy to you in the room.

Clap your hands and listen carefully to the decay. If you are in a typical, untreated, residential space, chances are the decay will not be the even, full-spectrum reverb we expect from a burst of white noise, but rather a ringing or boinging sound. Maybe even one that changes in pitch or "flutters." Walk a few feet away and try it in a different part of the room and it will be a different sound or pitch. What you are hearing is standing waves. Instead of sounding like the decay of a gunshot, it sounds like some weird ethnic percussion instrument.

The effect might sound subtle in the room, but it will not be subtle at all when you record it and play it back. Your ears compensate for the acoustical space that you are in, but they do not compensate for the playback of recorded material very well. We walk around and never "hear" reverb unless we are in a parking garage or a stairwell or some other unusual space, but it is present everywhere. If someone were to lead you blindfolded through your house, you'd be able to tell what room you were in just from the quality of the silence and the sound of your breathing, even though you might never be aware of how the different rooms sound in everyday life. However, if you were to take a tape recorder and walk around your house talking to yourself, the differences in sound quality would jump right out of the speakers on playback.

It is very important to understand that these are not problems that can realistically be corrected with EQ. The frequency problems can be extremely narrow, and are time-, frequency-, and phase-dependent. These problems can only be properly addressed in the room.

The problem is a big and complicated one, but fortunately, the solutions can be quite simple. Read on.
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Old 11-24-2008, 04:43 PM   #19
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Part III - getting down to brass tacks

The challenges presented by standing waves can be basically divided into two areas: recording and monitoring. Ideally, we would have a perfect acoustical space for everything, but in practice it may be easier to tailor a multi-pronged solution. I'm going to start with approaches to recording, since the things we do to get good recorded sound are important anyway, and then get onto the fun part of creating a good listening room so you can evaluate and mix your now vastly-improved recordings. But everything applies to everything, and the understanding you get by working through both problems will improve every aspect of the process.

The first and easiest way to short-circuit the problems of standing waves in recording is to record bass instruments direct. Bass guitar, synths, and other bass instruments are very well-suited to direct recording anyway. We'll get to kick drum a little later. So there's one shortcut.

The second thing, and this is one of the most important things any recordist can do, is to pick up some kind of portable recording device or microphone and walk around the spaces that are currently available to you to record in and talk or sing into the recorder. Just do it. Chances are 100 out of 100 that some parts of your usable space will sound vastly better than others, and they may not be the places you would first think of. Do not overlook bathrooms, stairwells, and hallways. Get a guitar player to walk around with an acoustic guitar while you follow her with a mic. Try it with the doors open and the doors closed. Try it in the corner and in the other corner, facing towards and away. Try it with the mic pointed one way and pointed the other. Pick up the friggen snare drum and ride cymbal and carry them around to different places in the room than wherever your older brother left them when he moved to Ohio.

You don't have to suss out every square inch of the house, just spend an hour or so. The best part of this exercise is that you will start to attune your ears to the differences in spaces and you will begin to hear them without needing a recording rig. This is an invaluable skill for anyone who wants to make recordings. The second-best part is that you will learn to make acoustical effects work for you instead of being subject to their whim and mercy. If you can get good natural resonance and reverberation by recording vocals in the kitchen or putting a guitar amp in the bathtub, it will blow away anything you can achieve with plugins.

Your recordings are getting better already.

Next up, a look at acoustical treatment.

Last edited by yep; 11-24-2008 at 06:01 PM.
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Old 11-24-2008, 05:15 PM   #20
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Good stuff, yep. Keep going. Waiting on the next installment.

Any comments on treating spaces to improve on what "just happens to be there?" You know, so I can record vocals in my studio rather than the upstairs shower? Or is this all coming in the setting up a listening room part?

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Old 11-24-2008, 05:54 PM   #21
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Part IV - principles of down and dirty acoustical treatment

First off, you CAN make great pop recordings in a low-ceilinged space. And don't let anyone tell you different. Every single Motown record in the Detroit era was made in the low-ceilinged basement of Berry Gordy's house (originally with a dirt floor, no less). Blaming the room is just excuse-making. The list of brilliant records that were cut in lousy spaces is even longer than this thread. If you plan to record the Boston Symphony Orchestra in your basement, you might need to work a little harder, but if you were able to book them for the gig then you're already beating the odds.

Having a vaulted hardwood ceiling at your disposal for drums and pianos is a neat convenience, but the really critical space is where you listen and mix. The control room (or just the spare bedroom where your computer is) is where you make the critical decisions not just about mixing, but also where you evaluate your afore-mentioned walking-around recordings and everything else. So it's pretty important to minimize the most drastic effects of room resonances and standing waves in this space, even if you decide to cut your tracks in the laundry room.

Fortunately, you can treat this room in an afternoon for less than $100 (even less if aesthetics are no object). Will it be a world-class audiophile listening room? Probably not. Will it be a vast improvement over almost any listening space that non-professionals have ever been exposed to outside the movie theater? Probably so.

Here's the deal. What we want to do is to "trap" or absorb the standing waves (convert them into heat energy, to keep a pretense of science). I'm going to start by talking about the stuff that you *don't* want to do, because there is all kinds of misinformation out there.

We want to do this without creating a totally dead space. Especially if you are recording in the same room. In any case, an anechoic chamber is both nigh-impossible to create, and also a very unpleasant place to spend time in. Trust me.

First off, covering all the walls with 2" foam is one of the worst things you can do to create a pleasant, even, natural acoustic space. Acoustical foam has its place, which is in marketing brochures. (this is an exaggeration, but the over-use and misapplication of foam and egg-crates and egg-crate foam does so much more harm than good that it's not a bad starting point to think of it is as bad, and then find exceptions to the rule).

Secondly, you do not want to get into helmholtz resonators (proper "bass traps") such as panel traps or tuned clay pots or any of that. You can easily find resources on the web that will help you calculate your room modes and so on, but honestly, you do not even need them. In a small residential space, there is basically no such thing as good bass resonance. Getting all precious about calculating the frequencies you want to corral is not just over-kill, it's counter-productive. We just want to scoop up everything in the way of low-frequency standing waves and kill it. And you don't need to understand much in the way of theory to do this.

A little more on the topic of "tuned" solutions and why they are inappropriate for a home studio: In an acoustically-designed space, such as a classical concert hall, the designer has some very specific goals, typically contractual ones. For example, their design criteria might be even frequency response measured in 1/3-octave intervals, +/- 6dB in 80% of the seats, with a reverberation time of 60dB of loss after 2 seconds, and no more than 12dB loss of intensity from the front row to the back, and so on. These criteria mean that any additional absorption is potentially a deal-breaker. So if they have a 15-foot high balcony, that is going to create standing waves at say 40Hz and intervals thereof below the balcony, and they are trying to design the space to spec, which would include finding a way to tame that standing wave without soaking up any more volume intensity.

There are ways to do this by creating tuned resonant spaces with a certain proportion of size open to the treated space. If you have no life you can read up on it in McGraw Hill's Master Handbook of Acoustics or probably find some stuff on wikipedia or whatever. But unless you are designing a space with a million dollars hanging on whether row 28, seat 12b hears the unamplified orchestra at -8dB with +/- 3dB frequency response, it doesn't matter.

in the small, amplified, sweet-spot focused world of the studio control room, even in a million-dollar studio, we are perfectly free to just kill ALL the bass resonance and call it a day. In fact, this is not just a shortcut, but is actually the best approach to take in a small room with amplification, acoustically speaking.

One of the really cool things about random is that it is still random even if you randomize it some more. E.g., if you have a beach that is made of sand with some rocks in it, and you scoop out all the rocks and some of the sand, then it is still a beach made of sand, and is indistinguishable from a beach where someone forensically picked up each rock and carefully brushed every grain sand back onto the beach.

So it is with acoustics. What we want is random. Random resonance, random decay, for a nice, even, natural reverberation, and preferably a fairly short one. What we don't want is the non-random, localized, frequency-specific resonances that room modes produce. If we can scoop out all of the non-random stuff, and we get some of the random stuff as well, then who cares? The random stuff that is left over is still random. No more and no less random than it was before.

Moreover, it's not only easier but also a lot more effective to clear a beach of rocks with an overkill approach. We don't need a bunch of geologists on their knees with calipers and toothbrushes to sift the beach, and we don't need any calculations or fancy resonators to soak up problematic standing waves. What do we need?

BROADBAND ABSORPTION. How do we get it? To be continued...

Last edited by yep; 11-24-2008 at 10:04 PM.
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Old 11-24-2008, 07:20 PM   #22
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Part V Treatment principles

BROADBAND ABSORPTION is the name of the game. Easier done than said, but watch it! Both words count equally. ABSORPTION THAT IS NOT BROADBAND IS WORSE. Read that again, because Auralex all over the walls is the albatross around the neck of the well-intentioned home recordist. BROADBAND ABSORPTION. BROADBAND. BROADBAND. If you don't know what this word means then keep reading and don't stop until you understand it.

I am going to waste a paragraph on terminology. I have plastered this post with BROADBAND because I am about to switch terms and start calling BROADBAND absorbers "bass traps." I am going to do this because I would rather gouge out my left eye with a corkscrew than have it be said that some poor fool hung up a bunch of Auralex because yep said all you need is absorption. Some excruciatingly technical person is going to howl in protest that broadband corner traps are not bass traps. They will be technically correct, but that will not stop my onslaught of using the terms interchangeably. See above post for comments about proper bass traps. In the current colloquial parlance, particularly when it comes to small studio design, "bass trap" has come to mean something primarily designed to soak up low-frequency standing waves, and broadband corner traps fit the bill.

Broadband bas trapping is easy. All you need is deep absorption, preferably in the corners of the room. The reason why corners are better is twofold:

1. Like the billiard balls above, standing waves tend to settle into corners.

2. Trapping across corners gives you a lot more exposure to surface area and wavelength than similar traps on flat surfaces.

2b. As luck would have it, corners also tend to be convenient places to put the things.

Expanding on 2 a little bit, the golden rule when it comes to absorbing low frequencies is that you want absorption that is at least 1/4 of the wavelength deep. To expand further, a neat trick about absorption is that empty space between the absorber and the wall is almost as good as having that space full of absorption. In other words, a 2" deep absorber suspended 4" from the wall is nearly the same as a 6" absorber affixed flat against the wall. Even cooler, waves that hit the absorber at an angle count for the full distance they travel from when they hit the absorber to when they leave the absorber out the other side.

In other words, if a standing wave comes into a corner trap at an angle, the effective "absorption distance" counts from where the wave enters the absorber, bounces off the near wall of the corner, hits the far wall of the corner, and ends where it passes through the absorber again. So a 2'x4' panel hung across a corner with a 6" gap behind could catch a standing wave at an angle such that it gives nearly equivalent performance to a four-foot deep absorber or more. (if I were not incompetent with the interweb and computaters I would make a diagram. Maybe someone smart will help.)

Of course, a bona-fide four-foot-deep absorber would catch a lot more standing waves at a lot more angles, BUT if we get some fairly small and unobtrusive panels hung in three-way corners and along the ceiling, we can catch a LOT of standing waves while barely affecting the usable space in the room.*

So what makes a good bass trap? Anything dense, deep and absorbent. Old mattresses stacked in the corners will rival anything an acoustician can offer. Bales of hay or rolled bundles of pink fiberglass with the wrapping still on will work wonderfully when stacked floor-to-ceiling. Putting a sofa or a bed in the room is solid gold, especially if it's in a corner. An open closet full of clothes or open drawers in a dresser is a great broadband absorber. Even dirty laundry shoved in the corners of the room works, for you starving-musician types out there.

But of course, the real star of the show, the act you've all been waiting for, the professional-looking, amateur-costing, minimal-space-consuming, acoustician's-best-effort-performing product is the HOMEMADE CORNER TRAP (a.k.a DIY Realtrap knockoff).

Before I get into it, I want to give a quick plug for Ethan Winer's RealTraps. Ethan is a legend in the making, an extraordinarily helpful and knowledgeable guy, and has done more to advance the real-world understanding of acoustics among both professional and amateur studio operators than anyone in history. His RealTraps are the de facto industry standard for out-of-the-box acoustical treatment, and he is as happy to help with ripping off his products as he is when it comes to selling them. His line of RealTraps are essentially premade, ready-to-mount, good-looking panel absorbers that have all the kinks worked out of the design. He would not mind my telling you that you can make your own cheaper, but you can't get better than what he produces. His website is a treasure-trove of real-world acoustical knowledge, whether you use his products or not. RealTraps are the REAPER of the acoustical world, and if you are in a position to spend money where it's due, you can buy genuine RealTraps for not a lot more than hacking your own DIY knockoffs.

That said, next up is the money shot, making your own corner traps....

*(If we can additionally get a rug with a heavy pad on the floor, or hang something similar from the ceiling, it won't do much in the way of bass-trapping, but it will give us a lot of flexibility by way of having one dead and one live direction to angle mics along the shortest dimension of a typical room. ((Incidentally, a conventional drop-ceiling of 2x4 hardware-store acoustical tiles is one of the best room treatments you can ask for, as long as it doesn't rattle, and especially if there is some fiberglass insulation above. Although it is profoundly unglamorous-looking))
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Old 11-24-2008, 09:13 PM   #23
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Part VI - How to treat a typical residential space for less than $100 in a single day.

Materials needed:

- 2'x4' Rigid fiberglass insulation panels (aka Owens-Corning 703 or 705, aka rockwool, aka mineral wool, aka mineral board, aka ductboard). This is the key ingredient and is NOT available at Home Depot, Lowes, or conventional hardware stores. You have to order it from insulation companies or industrial supply houses. Denser and thicker is better, but if you're doing corner traps with air gaps behind, pretty much any of it is fine. In the US, a company called SPI (Specialty Products Inc) has a lot of semi-retail branches that sell 2"x2'x4' panels for around $40 per bundle of 6. Check the yellow pages and make a couple calls.

Total $40

- Fabric. this is important to wrap the panels in, since you don't want mineral fibers floating around the room. Pretty much anything is fine. Burlap is great. If you can blow through it easily, it's acoustically transparent, but that hardly matters until you get to leather or something. Fabric typically comes from rolls that are about 2 yards (6 feet) wide. 36 linear yards gives you room to make mistakes. Ikea sells plain beige light canvas for 99c per yard. I'm guessing it's similar in metric countries.

Total $76

- Big wire ties (aka zip ties). Anyone used to coiling wire should be familiar with these. They are the same as the plastic zip-tie handcuffs you see on TV. They are great for hanging stuff because they are super-easy to adjust. Buy 50 or more of the longest ones you can find. you'll need four per panel (24), but it's better to have extra. Figure $10.

Total $86

- Fender washers. Four per panel for a total of 24. Purely for strain relief so you can use duct tape or anything else if you feel like it. Under $3.00

Total $89

- Glue gun. Whatever. You don't actually need a glue gun, you just need some way to affix the fabric to itself. A stapler can work, too. If you're good at sewing or something, that's better. If not, a glue gun is super-easy way to just shove it all together and it doesn't matter how messy the back side is. Buy the cheapest one-- there's nothing heavy-duty about this job. $7

Total $96

- Eye hooks. You need 12 to hang six panels, but buy 20. At 10c apiece.

Total $98

Stuff you should already have:

Gloves
Pen
Tape Measure
Something to poke through fiberglass with (screwdriver or chopstick is good)

So now that you have all your materials, put on a pair of gloves and some work clothes (you are about to handle fiberglass, and it's wicked itchy if it touches skin, so wear long sleeves and prepare to do laundry after).

Start with just one panel so you get the hang of it, then you can go production-line on the next five.

1. Measure spots for 4 holes about 1/3 lengthwise and about 1/3 crosswise on the panel. punch through the panel with a poker. Small phillips screwdriver or chopstick works great. This is not precision work, just get them roughly centered, or at least far enough apart so that there is enough fiberglass so they won't rip through.

2. pick one side of the panel to be the clean "front." Through the back, stick one of the zip ties through, then put two fender washers for strain relief on the front side, then loop the wire tie back through the other hole and loop it through to the bare minimum to fix the loop. There should be a generous loop in back left over. One fender washer should fall flat against each hole on the front, in case you are not smart enough to figure that out.

3. Spread out a generous stretch of fabric and set the panel, front-side-down, upon it. Pull the fabric up and and wrap it like a present, hacking it so the zip tie loops stick through, and seal it up with the glue gun. Nobody is ever going to see anything on this side, so don't worry about being messy. Have a beer or three.

4. Back in your control room, pick the spot for your first panel, and screw two eye hooks into the ceiling, approximately 6" from the wall and spaced about the same width as your zip ties are, maybe leaning slightly towards the corner so you get a good seal (this does not have to be precision work-- the adjustable zip ties will let you finalize it by eyeball).

5. Loop two new zipties through the eyehooks, but don't connect them. Lift up the panel and loop the eyehook-hanging ziptie closest to the corner through the ziptie that's already glued into the panel. Zip it just enough to close the loop (don't pull it tight against the ceiling just yet). Do the same with the second ziptie and then step back and take a look. There should be some slack. If your zipties don't easily reach all the way through the loop, use a third ziptie in the middle (like a chain-- eyehook ziptie, joiner ziptie, panel ziptie)

6. Reach under and pull each side tight just until the panel is touching both the ceiling and the wall. Pull the ties that are run through the eyehooks, not the ties that are run through the panels (this way you can re-use the panels). Don't over-tighten or fold the panel up into the corner, just get it more or less even with both the ceiling and the wall. This can be an awkward job, reaching behind and under the panels, but it's not complicated. Aesthetics are a bigger consideration than acoustics at this point. Keep in mind that wrinkles in the fabric will tend to even out over time, assuming your gluing was not *too* drunken.

You're done! Repeat with the other five panels, sticking them wherever you can, keeping in mind that three-way corners are best. The before-and-after difference will be HUGE in a typical residential room.

Last edited by yep; 11-24-2008 at 09:27 PM.
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Old 11-24-2008, 09:33 PM   #24
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Mistaken post. Might try more later.

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Old 11-25-2008, 11:42 AM   #25
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When tracking acoustic guitar, I noticed that certain notes stood out as unusually boomy in the mix. A little study revealed that it was probably the standing waves caused by slightly less than 8 ft ceilings (and harmonics above that).

Now, I know that the elite acousticians will say "always fix the room, don't depend on fixing it in the mix", but as a practical matter, I was able to set a parameteric equalizer to focus narrowly on the problem frequencies and pull them down just enough to where it sounded natural.

Negative effects ? I really didn't notice any. Maybe the "phase errors" would show up in a big mix. I don't know.
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Old 11-25-2008, 12:23 PM   #26
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Quote:
Originally Posted by Vyasa View Post
When tracking acoustic guitar, I noticed that certain notes stood out as unusually boomy in the mix. A little study revealed that it was probably the standing waves caused by slightly less than 8 ft ceilings (and harmonics above that).
You also could have experimented with the mic position... there might have been a more "even" spot to record it.

Yep, thanks for posting this...
I have read a lot of it before... and right now I'm thinking about building some absorbers and it's good for me to read it again...

Eddy

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Old 11-25-2008, 12:31 PM   #27
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Quote:
You also could have experimented with the mic position... there might have been a more "even" spot to record it.
Good idea; and I should have mentioned that I did try that.
In theory, all resonance modes will be cancelled at the exact center of a room. So I tyipcally had the guitarist very close to the center of a smnall room. But since this was a floor-to-ceiling resonance, and I was confined to normal chair height, I couldn't make the resonance disapp-ear by changing positions.....or at least I couldn't find any postion that did, moving both the mikes and the player.

Anyway, my only point is that, while room treatment may be preferrable, don't completely discout the idea of using parametric EQ. It does work in many "bad" acoustic situations. On that same subject: an automatic feedback eliminator is, in essence, noting the resonant frequencies of a room and then knocking the response down with a very high Q parametric equalizer, so recording through a feedback eliminator has worked for me also.
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Old 11-25-2008, 12:56 PM   #28
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Quote:
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In theory, all resonance modes will be cancelled at the exact center of a room.
Are you sure?? I have no theory to back this up, but I thought that the center of a room is not ideal...

And your point about EQ is taken!

EDIT:
I've looked up some articles (http://www.realtraps.com/art_room-setup.htm) and you're right, the resonance modes are cancelled in the center. But I think the center is not the ideal place to listen or record...

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Old 11-25-2008, 03:21 PM   #29
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Quote:
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Are you sure?? I have no theory to back this up, but I thought that the center of a room is not ideal...
yea, how i understand it, it's the other way around.
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Old 11-25-2008, 03:51 PM   #30
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Actually, I am not really "correct". The LOWEST resonance mode always has a null at the center of the room, but higher harmonics may have peaks there.
Swiped from another site:
Quote:
"The first resonance peaks for any given room dimensions occur at room boundaries. For a 14-foot-wide room, a 40.3-Hz peak occurs at the each side wall. The null for this frequency occurs halfway between the two walls. If you sit dead-center, you'll probably hear a dip in the frequency response at about 40.3 Hz. This spot will also have a peak at the resonant frequency's second harmonic, 80.6 Hz. The second harmonic will also have nulls about a quarter of the way from the walls (see figure 6). The center spot will have another dip at 120.9 Hz, the third resonance (which has nulls one-third the distance from the walls) and a peak at 161.2 Hz, and so on.

Now, move your speaker along the front wall to the first resonance's null, which is the middle of the room's width. When you energize the room with the resonant frequency of the width (in our case, 40.3 Hz) from the null of that frequency (the middle of the room's width), the response should be less boomy. Unfortunately, the speaker's also playing at the peak of the second harmonic, which means that, when you play 80.6 Hz, the response will be even louder. "
All modes will have peaks at the walls, so that is where you definitely don't want to be close to. For other positions, it becomes a very complicated modal analysis that involve all three dimensions of the room.
Higher frequencies are dissipated and absorbed more easily than low frequency resonances, so that is why there is so much greater concern about the lower ones. High frequency modes exist in theory, but as a practical matter, the are dissipated enough to not be a big problem.
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Old 11-25-2008, 06:59 PM   #31
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Quote:
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...I know that the elite acousticians will say "always fix the room, don't depend on fixing it in the mix", but as a practical matter, I was able to set a parameteric equalizer to focus narrowly on the problem frequencies and pull them down just enough to where it sounded natural.

Negative effects ? I really didn't notice any. Maybe the "phase errors" would show up in a big mix. I don't know.
Let's back up for a second.

Assuming that there were acoustical effects due to standing waves embedded in your recording, ordinary eq would not "fix" them any more than you can make a miked solid-body electric guitar sound like a great acoustic by applying eq.

However, the fact of the complexity of acoustical effects does not in any way imply that room artifacts are necessarily "bad," they're just there, like the different resonances of an acoustic guitar. Acoustical effects are what make a viola sound different from a piano or a woman's voice, even if all three are playing the same note with similar dominant harmonic overtones. The difference between instrument designs and bedroom studios is that bedrooms are rarely designed with hundreds of years of acoustical trial-and-error in mind.

We would not consider an acoustic guitar to be "fixed" if we eliminated the resonances (yes, standing waves) that were designed into the instrument. The ideal acoustic guitar sound is NOT the pure sound of steel strings, not even close.

I put so many posts above the actual recipe for room treatment is for exactly this reason. Few singers sound better in a dead iso booth than they sound in the bathtub, and the bathroom can be a great place to record all kinds of stuff, even though it is probably the most distorted room in the building. But it is almost certainly not the ideal place to use as a control room.

The only criterion that matters for making recordings is whether they sound good. Technically, you could say the same about mixing, but mixing and evaluation decisions usually require a certain degree of reproducible accuracy. If you're getting great recordings without having to think about acoustics, then more power to you.

But for a lot of home recordists, there is a frustrating gap between the satisfying sounds they achieve in the real world, and the unsatifactory sounds they are producing on record. And some attention to acoustics can help.
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Old 11-26-2008, 03:11 AM   #32
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I glad you cleared that up Yep, in a nut shell, if it sounds good, it is good.

I have found the best spots for recording are indeed near a corner of my room.
I surmise this is because of the difference in refelections, ie very short ones from the wall, and the longest ones from the other parts of the room, as opposed to ones of similar length converging at the same place.

I also find, believe it or not that playing acoustic guitar in my space sounds good about 2 - 3 feet in front of a long mirror (please no jokes), I thought I was imagining it at first, but it works the same way as your vocalist in the bathroom in principal, it sounds a little bit similar to an exciter.

Reminds me of the time I asked a tree surgeon the correct way to prune this tree I had, his answer?

"There is a right way and a wrong way to prune that tree.......
.... and they both work!"
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Old 11-26-2008, 07:46 AM   #33
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This is an excellent thread! Your very clear description of acoustics has opened up a world to me. I picture myself in the not-so-distant future, walking around my basement with a microphone, clapping my hands and listening to the recording. I can also picture mic cables running upstairs to my bathroom.

Please keep posting!
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Old 11-26-2008, 12:39 PM   #34
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Readers of this thread may be interested in things like "shooting their rooms"; which means doing a spectrum analysis of their rooms with a spectrum analyzer.

This is one that I have had my eye on for a long time, but I haven't really tried it:
http://www.trueaudio.com/

I had good luck compensating my rooms with the very inexpensive Behringer untracurve pro. It had a built-in RTA (real time analyzer). But think I will try out the TrueAudio RTA as soon as I get time.
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Old 01-22-2009, 10:16 AM   #35
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Quote:
Originally Posted by yep View Post
Part VI - How to treat a typical residential space for less than $100 in a single day.
Here is a tutorial I wrote a few years back essentially outlining all of this.... with pics for those who like that sort of thing:

http://audiominds.com/forums/index.php?topic=3320.0
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Old 01-30-2009, 04:50 AM   #36
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Quote:
Originally Posted by Bubbagump View Post
Here is a tutorial I wrote a few years back essentially outlining all of this.... with pics for those who like that sort of thing:

http://audiominds.com/forums/index.php?showtopic=3320
Would you by chance have another link to this? Audiominds isn't accepting registrations anymore
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Old 01-30-2009, 12:05 PM   #37
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Give us a few days. We are moving to new board software after which it will be wide open again.
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Old 01-31-2009, 06:00 AM   #38
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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   #39
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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   #40
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Quote:
Originally Posted by ringing phone View Post
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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