Old 05-01-2007, 06:58 AM   #1
anytime732
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hi,

i am curious to know if the sound that i get from my monitor speakers (fostex PM2 mk2) is true enough to mix a good song on.

i do not currently have any bass traps or any other acoustic treatment, however i do have the walls and the ceiling covered in carpet. i also have a huge server rack where i keep my rack equipment and im not sure if that will be up setting the acousitcs of the room as it is a 6ft tall metal case basicly!! half of the height of the walls is made of breeze blocks and he top hald of the walls is made of wood.

if any one knows of any way to est or improve the quality of the acoustics in the room please comment.

a pic can be dfound here; http://a661.ac-images.myspacecdn.com...bcc8d42454.jpg
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Old 05-01-2007, 09:45 AM   #2
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ive been round the monitor issue too many times in my life.
soffits/desktops etc etc .
and i dont think there is a perfect solution no matter what one spends.
an engr in LA gave me the best advice cos i dont purport to be
a gold record mixer. as follows.
try to mix n check mixes on a variety of mediums.
earbuds/mono car speakers/home hifi's up to larger speakers if you can. and i feel he is right.
cos ive seen even good mixes break down on playing back on
junk speakers. which is unfortunately what a lot of consumers have. in summary a v difficult topic to address with no perfect solution imho.
my latest love for monitoring is a little curtis 20 buk
cd/radio/clock device to see if mixes dont work on it.

some people have told me thay like the new avantone brand for mixing. not exactly cheap but not very expensive. ITS A TOUGH TOPIC !
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Old 05-01-2007, 02:17 PM   #3
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.
cos ive seen even good mixes break down on playing back on
junk speakers. which is unfortunately what a lot of consumers have.
Then they aren't good mixes. They are mixes that sound good on a particular set of speakers in a given room -- all of which is incredibly coloured if you don't have properly balanced acoustic treatment.

What most people do not seem to understand is that all rooms are essentially a filter . . . and especially small rooms . . . one big resonant comb filter.

Quote:
in summary a v difficult topic to address with no perfect solution imho.
The only thing close to a perfect solution is a well balanced monitoring system with excellent, properly controlled acoustics (and believe me there are a good many studios, even multimillion dollar studios that are putting out major releases, that have less than optimal acoustics).


I do agree that it is very helpful to have a couple of options for checking your mixes on different systems. But proper acoustics treatment can indeed make this much less of an issue. With properly balanced acoustics, you will generally find that your mixes will translate much better, and you can get your mixes to that point much more quickly, with less running back and forth to the car, etc., than with less than optimal acoustics.
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Old 05-01-2007, 02:33 PM   #4
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i was considering replacing my pm'2 with a set of krk rp-8s would that be a good idea seen as i am in a position to swap for free?
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Old 05-01-2007, 03:04 PM   #5
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i was considering replacing my pm'2 with a set of krk rp-8s would that be a good idea seen as i am in a position to swap for free?
Did you actually read any of the above?

Lots of good advise there that buying speakers wont change.

That said, try them out, if you like them better trade. Without first fixing the acoustics, the speakers wont help much.
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Old 05-01-2007, 02:04 PM   #6
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Originally Posted by anytime732 View Post
hi,
i am curious to know if the sound that i get from my monitor speakers (fostex PM2 mk2) is true enough to mix a good song on.
The Fostex monitors are **OK**, but not great (IMO they suffer from a lack of inner/transient detail, and a fairly shallow front to back imaging), BUT . . . they should be good enough to get some pretty decent mixes on.

HOWEVER, from reading your description and looking at the picture, I can *guarantee* that your acoustics problems are BY FAR greater than any possible weakness in your monitors.

To give you a starting point, have a read of my post in this thread (I make a chunk of my living as an acoustics consultant):

http://www.cockos.com/forum/showthread.php?t=7794

The original query in that post was slightly different from yours, but the answers are actually very much the same. Between what I've detailed in that post and what is contained in the linked articles, this should give you a good starting point.

Quote:
i do not currently have any bass traps or any other acoustic treatment, however i do have the walls and the ceiling covered in carpet.
Using carpet all over your walls like this is a VERY imbalanced way to treat the acoustics of a room. Not that you should never use carpet for absorption, mind you . . .

The problem here is that carpet will only absorb high and mid frequencies, and it will not absorb low frequencies. Unfortunately, if you put in a whole bunch of high and mid frequency absorption without putting in equally as much low frequency absorption, you end up with an unnaturally dead, and MUDDY sounding room!

Quote:
if any one knows of any way to est or improve the quality of the acoustics in the room please comment.
In fact I DO know of a way to substantially improve the acoustics in your room!

The answer is bass traps . . . as many as you can afford to buy or build in your room.

While you can most definitely put too much high and mid frequency absorption in a room, it is pretty much impossible to put in too much low frequency absorption in a room, especially when we're talking about small rooms (i.e., the size rooms you find in a typical house or apartment).

This may seem counterintutive, but the fact of the matter is that the low frequency sound waves that are reflected off the room boundaries (walls, floor and ceiling) will cause acoustic distortion of the direct sound from your speakers by either enhancing (increasing the amplitude) or cancelling out (causing dips or even outright nulls in the frequency response) the direct sound waves coming from your monitors.

ALL rooms, and ESPECIALLY small rooms, need bass traps to get anything even close to a flat response. Most rooms will have peaks and nulls at numerous frequencies across the entire frequency spectrum having a range of a good 30 to 35 dB from top to bottom. If you address the room modes that cause the problems at those particular frequencies, you will not only reduce the amplitude (and also even out the decay time) of those problematic peaks, but also help to minimise or eliminate the dips/nulls. This means that, even though you are *absorbing* low frequency sound energy, you will actually be getting MORE bass (and and tighter, more accurate bass) than without the absorption.

So . . . it becomes a more than a little bit inconsequential to be worrying about whether your monitors are +/- 1 dB or +/- 3 dB of flat, if your room is acting like a huge filter/EQ that is skewing the frequency response of what you hear by 30 to 35 dB!

You will get more improvement (i.e., much greater accuracy) in that room by spending even $500-1000 (especially if you DIY) on proper acoustic treatment (i.e., broadband/bass traps, and balancing out the amount of high and mid frequency absorption so that you are not killing ALL the ambience in the room) than you will get in that room by spending even several thousand upgrading your monitors.

Another few articles that may be helpful to you:

http://www.realtraps.com/facts.htm

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

So . . . the short answer . . . fix your acoustics, and I wouldn't worry too much about your monitors until you treat the acoustics properly first.

Oh . . . and one other thing . . .

I would highly recommend getting those monitors OFF the desk, as I can guarantee you are getting some serious comb filtering from the sound reflected immediately from the speakers right off the surface of your desk. This will be skewing your frequency response, but it will also be playing havoc with your imaging.

I highly recommend to put them on stands, with the tweeters at ear height (or as close to it as possible).

Speaker stands should be as heavy and solid as possible, to avoid any low frequency resonances that could also cause your tweeters to move just enough to cause time smearing (which again mucks with your imaging).

The cheapest, easiest, and best solution for this I know of is to get a bunch of concrete breeze blocks and stack them up (you can glue them together with construction adhesive if needs be, to avoid instability and/or the potential that someone could bump into them and send the whole stack tumbling).

Concrete has a very low resonant frequency (somewhere down in the single digits) -- much lower than the lowest frequencies your monitors are capable of producing. This will give your speakers a very stable pedestal to work against -- this can also help tighten up your low end (as well as your imaging), because the speaker cabinet will not have the freedom to move ever so slightly when you get powerful kick drum hits -- which it can if you have your speakers sitting on unstable stands/furniture, or stands/furniture which might have a higher resonant frequency.

Hope that helps!

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Old 05-02-2007, 11:24 AM   #7
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The cheapest, easiest, and best solution for this I know of is to get a bunch of concrete breeze blocks and stack them up (you can glue them together with construction adhesive if needs be, to avoid instability and/or the potential that someone could bump into them and send the whole stack tumbling).
There is a new idea for me. I have known to get dense speaker stands, but to use cinder blocks is a great idea (and really obvious when you think about it). I just gotta figure out how to pretty em up though.

<slight hijack> What is your opinion of something like the Auralex MoPADs alone on a desktop or in conjunction with a proper dense speaker stand?

</end hijack>
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Old 05-02-2007, 12:04 PM   #8
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There is a new idea for me. I have known to get dense speaker stands, but to use cinder blocks is a great idea (and really obvious when you think about it).
Cheap, too!

Quote:
I just gotta figure out how to pretty em up though.
I usually tell people they can just drape them in any kind of nice fabric that suits their decor. You can also paint them, but I'd think that draping them with fabric would be a more elegant solution.

Hehe . . . I recommended the cinder block option to somebody in a thread at gearslutz one time, and within about 8 or 12 hours of the time I had posted the suggestion (the guy was located in China, I believe), the guy had run out and bought some cinder blocks and sawed them all in half (to stack up the halves for 2 stands) . . . the dude sawed them with a HAND SAW, FFS!!! LOL. I was stunned!

Quote:
<slight hijack> What is your opinion of something like the Auralex MoPADs alone on a desktop or in conjunction with a proper dense speaker stand?

</end hijack>
For some situations, they may offer some improvements, but IMHO they are really not an ideal solution, because I feel they could still allow for a certain amount of (very miniscule) movement of the speaker that could give you some time smearing. But if you need them to isolate the speaker a bit from a desktop that is resonating like hell, and you need to get them up a little bit off the surface of the desk, or to angle the monitors down at you so that you'll be getting a little more "correct" angle of incidence from the tweaters to your ear, then I'd say they can certainly help a bit with these things if you don't have any other options . . . but there may be better solutions.

For example, it might be better to use a couple of concrete or marble, stone (or other heavy, dense material) slabs underneath the monitors than to use foam. But then again, it depends on how much of your problem is, for example, the result of an extremely resonant (and perhaps a bit wobbly) desk . . . you may need a greater thickness of concrete/stone, etc. than you want to risk stacking on that desk to get the isolation you need! Lead is another material that could work for that kind of isolation, but that can have its own drawbacks too (for the obvious reasons).

I think in the vast majority of cases you are best getting the monitors up on separate, heavy stands, rather than setting them on your desktop or a platform attached to a desk. If you have the monitors on separate, heavy stands, the MoPads aren't likely to offer any particular benefit (other than perhaps to angle the monitors down if that's needed, but in that case you are better to either build the stands to an appropriate height and/or make adjustments to your seating height, or use something else that's dense and heavy to introduce the angle).
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Old 05-01-2007, 06:12 PM   #9
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hi,

i do not currently have any bass traps or any other acoustic treatment
Ding! There's your problem.
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Old 05-02-2007, 05:17 AM   #10
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ok, ive spoekn to a friend who has the krk rp8's and i compared them to the pm2 and the krk sounded alot better and for a free swap i think it is worth the upgrade.......

as for the acoustic treatment, does anyone know of a way to build your own bass traps, i have looked at them on the net and for what they are they seem quite pricey i wonder if anyone knows where you can get the foam and shape it yourself that might beworth a try.........

i have found two types of tiles on ebay which i thinnk will do the trick just to calm the room down, et me know which ones you thiunk would be the best...

http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=320108479325

http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=320108104175
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Old 05-02-2007, 05:46 AM   #11
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Bubba's how to guide:

http://audiominds.com/forums/index.php?showtopic=3320

Forget about that foam stuff. It will do nothing for the low end and that is what usually needs the most help. And don't even think about using egg cartons.... that old piece of advice seems to pop up from time to time in these situations and egg cartons are just a bad idea.
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Old 05-02-2007, 06:33 AM   #12
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Anytime likes the KRK's cause he's heard mine, but I agree that also a lot of it is to do with room.

I moved my setup indoors for a bit and my mixes went all over the place, its amazing what a difference it can make.

Mixing at lower levels can compensate a bit whilst you sort out the acoustics.
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Old 05-02-2007, 11:10 AM   #13
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Mixing at lower levels can compensate a bit whilst you sort out the acoustics.
Not as much as a lot of people like to think, to be honest.

It might help a little bit in that you don't hear the ringing for quite as long, but the ringing is still there . . . just quieter in *exact* proportion to the amount you've reduced the amplitude of the direct sound (this is one of the many reasons why some people incorrectly believe that EQ can fix modal ringing).

Mixing at a lower volume also doesn't do anything at all to fix modal nulls.

Further, while there are many entry level monitors that do a pretty decent job at more standard mixing levels, you lose a lot of detail and accuracy when you monitor to lower volume levels with most of these entry level monitors.
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Old 05-02-2007, 06:38 AM   #14
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i must say that is a very impressive idea but..... my studio is not that big and if i where to kit it out with that size of traps here would be no room for me!!!!!

would it still have a significant effect if i where to 20"(width) traps on the between the ceiling and the walls as shown ( http://warsaw.innova-partners.com/~c...o/IMG_0284.jpg ) and then some pannels mounted flat on all four walls.........

i know that sounds a bit confising but would it have a good enough effect to justify doing it,,,,,,??
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Old 05-02-2007, 07:31 AM   #15
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Fill every corner you can (up and down, right and left, top or bottom) with rigid fiber glass, rockwool, or compressed fluffy fiber glass. Find every corner that is out of the way and fill it, or stradle it with at least 4" of the above. Hint; use the cieling corners to miantain your floor space. The back wall is reall an effective place to treat.

Put some absorbtion at your first reflection points. You can find these by using a mirror and a friend. Anywhere you can see a speaker in the mirror (your friend moves it around for you) from your listening position is a first reflection point. 2" of rock wool or glass will work.
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Old 05-02-2007, 09:03 AM   #16
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The foam panels you linked to are NOT bass traps. These will only absorb high and mid frequencies (and probably less effectively than the carpet you are using on the walls with this particular foam).

If you are going to use foam, you would need thick foam wedges to put in corners that are designed as bass traps, like these:

http://cgi.ebay.co.uk/2-off-3ft-Acou...QQcmdZViewItem

HOWEVER, while I am happy to see that this company (unlike a number of other companies selling cheap "studio foam" off ebay) provides certified lab reports, I can tell you from looking at their lab reports that the absorption specs on this foam is NOT very good, and you will be better building some DIY panels based on either Owens Corning 703 panels or the rockwool equivalent (i.e., same density) similar to Bubba's panels. I can assure you that these will be MUCH more effective, and will also have a much greater price/performance ratio.

There are a good many discussions on various forums about DIY 703/rockwool broadband/bass traps, with loads of interesting ideas and plans for building various types of frames for hanging these panels.

One good place to look (and ask) is Ethan Winer's acoustics forum here:

http://forums.musicplayer.com/ubbthr...tlist/Board/24

There's also the Sound on Sound "Studio Design & Acoustics" forum:

http://www.soundonsound.com/forum/po...=&Board=DESIGN

John Sayers' forum is good too:

http://www.johnlsayers.com/phpBB2/index.php

Quote:
Originally Posted by anytime732 View Post
i must say that is a very impressive idea but..... my studio is not that big and if i where to kit it out with that size of traps here would be no room for me!!!!!
Well . . . do you want accuracy or not? Low frequency room modes require mass, and a good amount of coverage, to address. Sorry . . . you can't defy the laws of physics!

It is very important to treat as much of your corner space as possible. You should start with the four vertical (wall/wall) corners, and then do the wall/ceiling corners

Any panels you mount flat on the wall should have a gap between the wall and back of the panel (I usually recommend about 3 to 4 inches).

This accomplishes a few things:

(1) it increases the low frequency absorption performance of those panels (i.e., the air gap causes it to act like a thicker panel), and

(2) it increases the amount of absorption surface that is usably exposed to the room.


Quote:
would it still have a significant effect if i where to 20"(width) traps on the between the ceiling and the walls as shown ( http://warsaw.innova-partners.com/~c...o/IMG_0284.jpg ) and then some pannels mounted flat on all four walls.........

i know that sounds a bit confising but would it have a good enough effect to justify doing it,,,,,,??
Yes, it would (though it will decrease the performance) . . . but it also adds to the difficulty in constructing the trap -- cutting fiberglass and/or rockwool is messy, itchy stuff.

I want to add another link that may be informative for you. To help you understand why it is so critically important to treat the corners of your room, read up on room modes and standing waves here:

http://www.isvr.soton.ac.uk/SPCG/Tut...ding-rooms.htm

This page has some excellent animations that show how low frequencies travel in a room, and demonstrates how all of the room modes gather in the corners. If you can interrupt the wave fronts at those corners, you will be able to reduce the amplitude of the reflected sound waves. Reducing the amplitude of these waves by even 6 dB in relation to the direct sound from your monitors will noticeably reduce the amount of acoustic distortion caused by the reflected sound interfering with the direct sound from your monitors.

Unfortunately for you, the smaller your room, the more you need bass traps!

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Old 05-10-2007, 08:43 AM   #17
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How big is that room? It looks really tiny.. if it's *really* small, bass trapping is probably going to be fruitless.

IMO the big thing would be to try to get your speakers set in a symetrical way in the room -

- get that right monitor away from the side wall; get both monitors away from the back wall...

- then decouple the speakers from your desk somehow; the cinder block thing..

- then try to eliminate your closest reflective surfaces; that's a pretty big, flat desk, put some fluffy cloth over it..


Otherwise, in a tiny room you'd have to figure out exactly which frequency in the bass is dominant through analysis, and then build a custom-dimensioned Helmholtz resonator to stop it.


/ funny, I have old memory sticks laying on my desk as well?
// and change...
/// and my "second monitor" is up to the right (which is ergnomically bad IMO, but if I had an LCD it would be side by side)
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Old 05-10-2007, 11:22 PM   #18
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How big is that room? It looks really tiny.. if it's *really* small, bass trapping is probably going to be fruitless.
. . . .

Otherwise, in a tiny room you'd have to figure out exactly which frequency in the bass is dominant through analysis, and then build a custom-dimensioned Helmholtz resonator to stop it.
Quite the opposite, actually. I've treated many very small rooms with bass traps, including small vocal/isolation booths. And you really need broadband bass trapping for this.

Just for example:

A 4' x 5' x 7' vocal booth will have axial modes at 141.25, 282.50 and 426.75 Hz related to the width (4 ft) dimension, 113.00. 226.00, 339.00 and 432.00 Hz for the length (5 ft) dimension and 80.71, 161.43, 242.14, 322.86, 403.57 and 484.29 Hz for the height (7 ft) dimension.

Those axial modes will create the strongest peaks and nulls, but you may also be more exposed to the effects of tangential modes in such close quarters.

Quote:
- get that right monitor away from the side wall; get both monitors away from the back wall...
Yes . . . definitely! He's basically got that one monitor seriously corner loaded, and is probably getting at a good 6 to 12 dB or so additional in the low frequency range from that corner loading.

Quote:
Otherwise, in a tiny room you'd have to figure out exactly which frequency in the bass is dominant through analysis, and then build a custom-dimensioned Helmholtz resonator to stop it.
For most small rooms, you simply need broadband trapping to cover all of the room modes (which can cause both extreme peaks AND extreme NULLS!). If, after broadband trapping, you still have one particular peaky/resonant frequency that is very stubborn, then maybe that is the time to use a tuned absorber like a Helmholtz resonator or tuned panel absorber.
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Old 05-12-2007, 07:06 AM   #19
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i'm curious.

I have alot of that thin carpet (about 1/8" thick) that is used to cover cabs. would that work for covering? or should I get something thinner? it's going on a bass trap that is going to be positioned behind the drummer who is also behind a shield in a 80x 25 room.
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Old 05-12-2007, 07:43 AM   #20
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i'm curious.

I have alot of that thin carpet (about 1/8" thick) that is used to cover cabs. would that work for covering? or should I get something thinner? it's going on a bass trap that is going to be positioned behind the drummer who is also behind a shield in a 80x 25 room.
Can you blow through the carpet? If not, it wont work as well.

Also, broadband traping is even more important in smaller rooms. Trap as much as you can. make the room COMPLETELY dead. There is no good reflections in a small room.
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Old 05-14-2007, 09:09 AM   #21
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Just for example:
113.00. 226.00, 339.00 and 432.00 Hz for the length (5 ft)
Where can he get a broad band absorber that *evenly* reduces 4 octaves at those *specific* frequencies, while not creating a valley elsewhere, that will also fit in a 4x5 room and still leave room for other stuff...?

If he's got a tiny (4x5) room, it's always going to have bass problems at appreciable volumes, even if he puts some of Winer's broad band traps in the corners - and then, he's not going to have a "room" left over.



Quote:
then maybe that is the time to use a tuned absorber like a Helmholtz resonator or tuned panel absorber.
Sort of like "in a tiny room you'd have to figure out exactly which frequency in the bass is dominant through analysis, and then build a custom-dimensioned Helmholtz resonator to stop it."
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Old 05-14-2007, 08:49 PM   #22
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Does'nt have to evenly absorb, or target, specific frequencies.

It has to absorb as much as you can fit/afford. You cant over do it.

That idea relates to killing the high frequency "air" in nice sized and shaped rooms. At lower frequencies, you want maximum absorbtion in any room. More so for the small ones.

You are correct in assuming that a 4x5 room is going to sound crappy no matter what, its just a matter of how crappy.

Traping can go on the cieling to wall corners just as well.
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Old 05-14-2007, 09:04 PM   #23
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Where can he get a broad band absorber that *evenly* reduces 4 octaves at those *specific* frequencies, while not creating a valley elsewhere, that will also fit in a 4x5 room and still leave room for other stuff...?
Chip, broadband absorbers DO NOT create nulls/dips in the frequency response. Rather, they actually REDUCE the severity of, or eliminate, nulls/dips in frequency response, as well as reducing peaks.

The peaks and nulls are BOTH caused by the phase interference of the room reflections with the direct source sound at various points in the room. If you put broadband absorption in a room, you reduce the reflections that cause both peaks and nulls, and therefore your entire frequency response evens out, and the decay time becomes more uniform.

If you can reduce the amplitude of those reflections by even as much as 6 dB or so in relation to the direct sound from source, you will noticeably reduce the severity of both peaks and nulls.

A lot of people get confused and think that putting absorption in a room can cause you to end up with LESS bass . . . but indeed you will get MORE bass where before there were nulls, and you will of course reduce the peaks.

Tuned absorption targets only one frequency or frequency range, and ignores all the rest . . . and therefore does not take care of all the other peaks and nulls that are absolutely there across the frequency spectrum (in ALL small rooms) whether you notice them or not. Most small rooms have peaks and nulls across the entire frequency spectrum somewhere in the range of 30 to 35 dB from top to bottom.

Some of those peaks and nulls occur in very narrow bandwidths, so a lot of times people do not notice them (especially the nulls) when they are listening in a room . . . but you will most certainly notice how much you were missing when you treat the room properly with broadband absorption, and you get back so much of the sound that was previously inaudible due to phase cancellation at modal frequencies. The other thing is that so many of those very narrow band peaks and nulls will get entirely missed by 1/3-octave band pink noise testing which so many people traditionally use for room acoustics analysis/RTA. That's simply not fine enough resolution to get an accurate sense of what's *really* going on in your room.

The bottom line is that ALL small rooms NEED broadband absorption to get anything even remotely close to an even frequency response. That is simply the best and most cost-effective way to treat small rooms, and I think pretty much any acoustician worth his salt will tell you the same.

So . . .

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then maybe that is the time to use a tuned absorber like a Helmholtz resonator or tuned panel absorber.
Sort of like "in a tiny room you'd have to figure out exactly which frequency in the bass is dominant through analysis, and then build a custom-dimensioned Helmholtz resonator to stop it."
My point being that your assertion that bass trapping (i.e. broadband bass trapping) would most likely be "fruitless" is *entirely* incorrect, as is your recommendation for a tuned trap (which, again, only addresses a very narrow band) to the *exclusion* of broadband trapping.

And back to this:

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Originally Posted by chip mcdonald View Post
Where can he get a broad band absorber that *evenly* reduces 4 octaves at those *specific* frequencies, while not creating a valley elsewhere,
Off the top of my head, I can't think of ANY absorbers/absorption materials on the planet (at least not that could reasonably be used for interior acoustics treatment ) in that have a flat absorption curve (unless you count an open window or doorway), and it is a huge (and unfortunately widely held) misconception that a flat absorption curve is needed (even if in certain instances it might be preferable), because of the principles I've discussed above.

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that will also fit in a 4x5 room and still leave room for other stuff...?
Typical panels made from at least 3-4 inch thickness of OC 703/705 (or the rockwool equivalent), be they commercially manufactured or DIY will offer SUBSTANTIAL improvement across the entire frequency range in a room like that (most definitely *including* even the lowest frequencies I listed as axial modes for that room). This will give you a MUCH flatter frequency response across the entire spectrum than using tuned traps in a small room such as this, and even using tuned traps you don't just use one and call it good . . . you have to have such absorbers evenly distributed throughout the room for best results, and preferably in the corners, where ALL of the room modes are present. This is where you need to break those wave fronts to get the most effective reduction of room modes.

Tuned traps are most often an inefficient use of space in small rooms, because the tuned traps will typically take up as much or more space as a typical broadband panel absorber, and will not lead to an *overall* flatter frequency response in the room unless used *in addition to* broadband traps.

So . . . if you treat a small room such as this with broadband bass traps and you STILL have one very stubborn low frequency peak, then -- and ONLY then -- you might consider adding a tuned trap . . . if you have room.

Last edited by scottdru; 05-14-2007 at 10:19 PM.
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Old 05-16-2007, 12:02 PM   #24
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Originally Posted by scottdru View Post

My point being that your assertion that bass trapping (i.e. broadband bass trapping) would most likely be "fruitless" is *entirely* incorrect, as is your recommendation for a tuned trap
He's talking about wanting to put something flat on the wall, and having basically a non-existent budget since he's talking about "trading up" to KRK 8's for the difference in what he has now - which I think is probably around about a $200 difference.

He can buy one broadband absorber from Ethan Winer for about that much.

So, in one situation he's got crappy speakers in a crappy room, but with *how much* of a low-frequency improvement? On the other hand he could have less crappy speakers in the crappy room that might have +/- *how much* of a difference - in an area where his crappy monitors has a sketchy/rolled off response to begin with?

If he gets the monitors he'll have a slight more accurate mid/high direct sound, same crappy room response (but maybe a better low end from the monitors to begin with); one presumes he won't be straddled with a 4x5 room forever, in which case skills learned on the better monitors would translate to a larger room AND he'd still have the monitors he's used to using.

I'd rather be in that situation, than to have a nice bass trap but having to listen to crappy monitors with my slightly-better-bass response-but-still-crappy room.


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if you treat a small room such as this with broadband bass traps and you STILL have one very stubborn low frequency peak, then -- and ONLY then -- you might consider adding a tuned trap . . . if you have room.

.. of course, he should have just had Storyk design his teeny tiny room to begin with, and he wouldn't have any problems to begin with. Simple!

The guy is obviously on a tight/non-existent budget and has crappy monitors. A $200 monitor upgrade is going to yield more returns than a $200 bass trap in his situation.

IMO.
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