room acoustics

[p_brane]

can anyone point me in the direction of any decent articles on room acoustics?

[RDR]

http://www.soundonsound.com/sos/jan0...eader_0108.htm

Any of the Studio SOS guides in sound on sound PRIOR to May 2007 are available free online, They give some brilliant real world examples of peoples studios and what was done to cure them.

[MARK ANXIOUS]

well, i had this question about 4 years ago when i really started to design a proper studio and stop fannying about with shitty bedrooms. the main issues are obviously nodes but unfortuntely you just can't change the size of your room in most cases to help this situation. so you have to use traps and foam and anything you know what to do to help solve the problems.

it was great cause at the time, the was a really huge article out in sound on sound, which really, really helped me and ever since then, i've recommended it to everyone who's asked me about the same subject.

i personally used auralex bass traps in each corner (i seem to remember them costing about 250 quid for the lot but FFS what a difference and OMG i couldn't live without them now) and built my own bass trap for the back of the room using this article (wow, this thing is incredible - you can feel the converted energy on the box, even at super low volumes)..

i've scanned in and uploaded the article. here's the link:

http://www.blackoutaudio.co.uk/audio...oTreatment.zip

[dirty_bass]

simple solution, especially if you live in rented property, buy the new jbl room correction monitors.
Stunning, and far better than faffing about with foam, unless you are an accoustic technician.
There is some great new room correction software out now, made by M-Audio I think??
I`ll find the link, but it works on the same principle as the JBLs, but is a lot cheaper.
Basically it analyses your room, and applies filters prior to your sound card output to correct for standing waves etc.

Other than that, bass traps in the corners (verticle and horizontal, anti-scatter/reflection tiles, to either side of the listening spot, and if the wall behind is close, just behind as well.
Possibly some deflectors directly above the monitoring position as well, to essentially stop any symmetrical modes being present.

All this can set you back a fair wack, more than 250.

I think the new room mode correction software costs about 250 AND it moves wherever your studio moves.

I plumped for the monitors, and man, I`m so happy I nearly cry every time I switch them on.
My mastering has improved so much since I got em

[p_brane]

cheers for the feedback guys,

@DB- dont think ill be forking out for any new monitors for a while yet so the JBL's are out. might have a look at some of the software progs though.

@MarkEG - magic mate will have a good read of this.

its a bit of an odd room really, rectangular with a window at one end and a stud wall jutting out the other, narrowing the room down to half its width. currently set up along the longest wall next to the window (its also my office). but me thinking i need to have a move around.

anyone know what effect having a window behind the monitors will make? oh there front ported by the way

once again cheers

[MARK ANXIOUS]

now, i was reading about room mode correction software. hmm this is very intererting. couldn't see anything by m-audio though???????

[MARK ANXIOUS]

cheers for the feedback guys,

@DB- dont think ill be forking out for any new monitors for a while yet so the JBL's are out. might have a look at some of the software progs though.

@MarkEG - magic mate will have a good read of this.

its a bit of an odd room really, rectangular with a window at one end and a stud wall jutting out the other, narrowing the room down to half its width. currently set up along the longest wall next to the window (its also my office). but me thinking i need to have a move around.

anyone know what effect having a window behind the monitors will make? oh there front ported by the way

once again cheers

well presumming you'll put the speakers on the wall with the window, the fact you've got a odd stud wall coming out at the back is great i would have thought cause it'll bounce the bass energy off in all sorts of directions and get rid of alot of it. also the window sounds good cause then alot of your bass energy will bugger off through the window and not be reflected back. i would work on a huge bass box at the back though (use that link i sent you to construct it) and definitely bass traps (you can order these like i did or if you're on a budget, that article tells you how to make these too)

good luck man!!!

[p_brane]

well presumming you'll put the speakers on the wall with the window, the fact you've got a odd stud wall coming out at the back is great i would have thought cause it'll bounce the bass energy off in all sorts of directions and get rid of alot of it. also the window sounds good cause then alot of your bass energy will bugger off through the window and not be reflected back. i would work on a huge bass box at the back though (use that link i sent you to construct it) and definitely bass traps (you can order these like i did or if you're on a budget, that article tells you how to make these too)

good luck man!!!

cant seem to find anything on the net about how windows effect the output. think i'm gonna move my desk around so the windows directly bhind the monitors, give it a try. the only thing then is that they'll both be bout 6" from the room corners which isnt ideal. but i know what your saying about the partition to the rear of the room, boy does the bass sound boomy stood there.


time to have a look on the sos website me thinks

[MARK ANXIOUS]

i have just done a load of reading up on this arc thing and my conclusions are simple. DONT buy it!!!!

Revolutionary Audyssey MultEQ® technology corrects frequency and phase response not only for the engineer’s ‘sweet spot’, but also multiple points in the room
...
Sonically ‘treat’ your room – get the sound of a $50,000 treated room for a fraction of the cost – so you can finally trust the sound of your studio


what a load of bollocks. the eq system is meant for home cinema, not professional music studios. seems to me like jbl are using a similar type of technology to this too, just to sell sub-standard monitors. mind you, they work for dirty, so there's something in them. hmm i need to check this shit out. i might order a pair of these jbl's on a 14 day money back thing and see what happens.....

until then, where did i put those hair clippers?? hehe

;)

[dirty_bass]

cant seem to find anything on the net about how windows effect the output. think i'm gonna move my desk around so the windows directly bhind the monitors, give it a try. the only thing then is that they'll both be bout 6" from the room corners which isnt ideal. but i know what your saying about the partition to the rear of the room, boy does the bass sound boomy stood there.


time to have a look on the sos website me thinks

Windows are highly relfective to highs and mids, so you may get some reflection problems.
I`d get some damping behing the monitors on windows to scatter the sound, otherwise you may find you get a slightly too toppy response, with odd delay.
As I said earlier, you basically want some kind of deflective surfaces around the listening spot, so to the left and right of the listening spot, on the walls directly opposite each other. On directlyabove the listening spot as well.
You don`t necessarily need foam tiles.
For top and mid frequencies, irregularly packed book shelves etc will do just as well.
You are basically trying to scatter the sounds to sopt any regular reflections causing trouble in the stereo filed, and boomyness.
Some diffusion in the "mirror" spots of the monitors will also help. Essentially, imagine the rear wall is a mirror, and whereever the moniros are reflected in the mirror, you also want to place some kind of scattering.
Don`t over damp a room, otherwise you will get a dead response making your mids and tops absorbed too much, and destroying a natural moitoring sound.

Bass nodes, standing waves can be a problem.
Get a synth, make a pure sine wave sound.
Draw in a declining scale in the low octaves (tdown to the point where the sound becomes inaudible).
Play this scale on repeat and sit in the listening spot.

Listen out for volume changes on notes in the scale.
And dips or rises will mean you have some nodes.

You`ll want to kill the bass energy with very very thick loose particle or breathable material (the air needs to pass all the way into the material for the soundwave to be fully damped, rather than reflected).
Rockwool, or insulation.
Or commerical bass traps.
Problem areas will be top corners behind the monitors, but really it`s a very complicated problem with the bass.
Walking around the room with above bass scale playing may help in locating problem areas.

Essentially you want as little symmetry between opposing surfaces as possible, and some good deep loose material to absorbe low bass waves.

Or use some RMC software.

[Jay Pace]

simple solution, especially if you live in rented property, buy the new jbl room correction monitors.
Stunning, and far better than faffing about with foam, unless you are an accoustic technician.
There is some great new room correction software out now, made by M-Audio I think??
I`ll find the link, but it works on the same principle as the JBLs, but is a lot cheaper.
Basically it analyses your room, and applies filters prior to your sound card output to correct for standing waves etc.

Other than that, bass traps in the corners (verticle and horizontal, anti-scatter/reflection tiles, to either side of the listening spot, and if the wall behind is close, just behind as well.
Possibly some deflectors directly above the monitoring position as well, to essentially stop any symmetrical modes being present.

All this can set you back a fair wack, more than 250.

I think the new room mode correction software costs about 250 AND it moves wherever your studio moves.

I plumped for the monitors, and man, I`m so happy I nearly cry every time I switch them on.
My mastering has improved so much since I got em

Hmmmm

I read up lots on the software. There's free stuff available - FIR filters that you can input into EQ and modelling programs that will even run as VSTs. The free stuff is very unfriendly to install and set up though if you don't know linux. And you need a measurement microphone to calibrate the impulse response.

I read a fairly good thing on SOS about the principles behind it not really making sense. That you can't correct a room, and applying an EQ curve and filter over the output is just adding another layer of wrong over the original perception of wrong. Plus the room is only 'corrected' at the exact point the measurement is taken. Move your head out of this exact point and your listening to something else entirely.

The general gist I got was the you can compensate a little to improve things, but you can never correct a room using filters and the only way to properly do it is to acounstically treat the room.

All a bit out of my depth, but made intersting reading. Was one of the audio geeks at SOS writing, will see if I can dig it out.

[dirty_bass]

Nah, that`s pish, I had a chat with some of the guys at the Music Producers Guild (I suggest anyone serious about music join up, although their meetings are in london most of the time), most of the new algorythms for room treatment are sound.
Essentially it`s only the bass which causes real problems that can`t be easily solved, and due to things like phase cancelation, these can easily be dealt with to a degree good enough for most house studios.

Once you get into mastering, in a serious way, then you might need to look a bit deeper as you start moving into the wonderful world of anal retentive micro frequency listening and the joyful practice of identifying the frequency of a sound by ear, and then being able to quote where on the musical scale it sits.
If you aren`t looking to go this way (like I in my nerdy way am) then room mode correction is fine.
The JBL monitors aren`t being raved about by everyone in the pro community for nothing, they really do make a huge difference, and are probably more effective than a total amateur trying to correctly sound treat their room with tiles (which can go incredibly wrong as well, not all accoustic treatment is good accoustic treatment, and more treatment isn`t always better than minor treatment)

If you are getting into this area of listening standard then you really should start looking at your electrical schematics and moving from balanced to unbalanced connections in your audio path, as you will get a more transparent sound as well.
You enter a whole new world of things you can do when you get into that side of things, and I could add more to the list, but to keep things short, for most people producing techno on BOA, basic budget room treatment and also the possible addition of room mode correction will be the more economical end effective route.

[MARK ANXIOUS]

Once you get into mastering, in a serious way, then you might need to look a bit deeper as you start moving into the wonderful world of anal retentive micro frequency listening and the joyful practice of identifying the frequency of a sound by ear, and then being able to quote where on the musical scale it sits.
If you aren`t looking to go this way (like I in my nerdy way am) then room mode correction is fine.

surely, everyone SHOULD be going this way. ok if you're after a quick 12 inch release until the bank manager gives you that loan to start that hairdressing business, then great but if not, you need to get your studio treated properly. ideally a room within a room, with all the treatment would be good but it's not always practical unless you work for sony - but hey, who says it wont be in the future????

all depends on how serious you are about it like you say ;)

[TechMouse]

ok if you're after a quick 12 inch release until the bank manager gives you that loan to start that hairdressing business

That was Plan B, was it Mark?

[dirty_bass]

hmm it wasn`t M-Audio
the one I have found is
ARC by IK Multimedia

http://www.ikmultimedia.com/arc

More pricey than the one I saw before, it was in a trade mag for mastering gear, and it was cheaper.
I`ll try to locate it in my magazine shelf later

[Jay Pace]

So if all the jbl's are doing is applying an EQ curve - could this not be replicated using any other system?

Like this one?
http://drc-fir.sourceforge.net/

I'm sure the jbl's are great, but are they worth buying just to take advantage of an eq curve that could be achieved through running a piece of software and overlaying an EQ curve?

Am really in two minds about whether to sell my mackies or not. Am already worried about the cost of shipping all my kit over to argie, and it might be cheaper to sell them and buy the jbls over there if they really are that great...

Appreciate your input stevio

[MARK ANXIOUS]

So if all the jbl's are doing is applying an EQ curve - could this not be replicated using any other system?

Like this one?
http://drc-fir.sourceforge.net/

I'm sure the jbl's are great, but are they worth buying just to take advantage of an eq curve that could be achieved through running a piece of software and overlaying an EQ curve?

Am really in two minds about whether to sell my mackies or not. Am already worried about the cost of shipping all my kit over to argie, and it might be cheaper to sell them and buy the jbls over there if they really are that great...

Appreciate your input stevio

exactly, that's what i'm thinking. what exactly is ths eq software? links?

[dirty_bass]

So if all the jbl's are doing is applying an EQ curve - could this not be replicated using any other system?

Like this one?
http://drc-fir.sourceforge.net/

I'm sure the jbl's are great, but are they worth buying just to take advantage of an eq curve that could be achieved through running a piece of software and overlaying an EQ curve?

Am really in two minds about whether to sell my mackies or not. Am already worried about the cost of shipping all my kit over to argie, and it might be cheaper to sell them and buy the jbls over there if they really are that great...

Appreciate your input stevio

Well the free software you linked to, just generates the FIR correction filters.
So you still need other processing software, plus a mic, and also to really know what you are doing.
I`m sure it could be a cost effective method, but it`s all a little bit too convoluted.
I wanted new monitors so I could have a dual monitor A/B setup for even better monitoring for my mastering. The JBLs are great monitors anyway, but with room correction and after demoing them, I just couldn`t logically get anything else. You set up the mic, push a button and wham, all done.
And if I move at the end of the year (off into the country I hope) then I can set up my new place nice and quick.
I hate Mackies anyway, which is another matter altogether. I find them too sharp on the top, and not pushy enough in the mids, so I`d sell em if I had em anyway, down to personal taste, but I do prefer the traditional type of monitoring from the NS10 era (I used to use Sprit Abs 2 up till I went to the A/B setup, and I`ve been through loads of monitors, mackies, events, K rock, but the Abs 2`s have stayed with me), so my opinion is just a matter of taste.

If I was you, I`d either, get some basic room treatment done. A few scatter tiles, maybe a few bass traps in the serious problem areas.
then get the JBL`s or RMC software and keep the mackies (blargh, I`d at least invest in some adams instead of mackies). Shipping the mackies will add crazy cost anyway, and not worth it in my opinion.

[Kokotorobot]

doesn't all this eq software correction totally **** up the sound with phasing + kills your CPU reserves? i'm skeptical on this

[dirty_bass]

doesn't all this eq software correction totally **** up the sound with phasing + kills your CPU reserves? i'm skeptical on this

no, and yes.
I think in terms of CPU usage it is an extra load.
Which is why I plumped for the monitors.