Gonna put out some general stuff on room acoustics. The is all very 101 stuff, but can make a big difference in the sound of recordings in a project studio. If you're having problems with the acoustics in the room where you record, mix or both - then you may want to look into some of these concepts on the road to finding a solution.

First, before we worry about any bass treatment, let's deal with the four walls - and what's on them and why.

Whatever wall your speakers are backed up to - that's the FRONT wall.

The wall back behind where you sit is the BACK/REAR wall.

The walls on either side are the SIDE walls.





This topic isn't necessarily about Primacoustic, it's just that they do have good conceptual illustrations.

OK, first theory we're working with is LIVE END / DEAD END. In this case the DEAD end is going to be the front wall - behind the monitors. That's where you're going to put the most amount of panel. I would say a 4' tall X 8' wide is about the right system for most project studio systems. The purpose of the panel on the front wall is to absorb the acoustics in the middle portion of the wall behind the speakers.

Notice the approx 4' X 8' total panels in the pic on the front wall behind the speakers. It should be placed starting approx 3' off the floor and topping out around 7' - with 4' tall panel/s.

Speakers will typically sit with the tweeters about 48" off the floor - which is also about the average height of a person's ears off the floor while seated in a chair.

The back wall is a different matter. You can put material on it, but it still needs to be more live, because, ideally, you want to use the least amount of absorbtion possible. So, by the time you already have a big 4' X 8' dead panel on the front wall, you want to be very sparring about the kinds of materials you put on the other walls in the studio/control room. The purpose of the back wall is to diffuse the sound hitting the back wall from the speakers. And also acoustically, to balance for the dead wall on the front wall.

Here's a back wall. In nice studios you'll often see randomly-spaced wood planks on the back wall. The idea of the diffusor is to spray the sound waves into patterns in the room that are not parallel, thereby reducing comb filtering and phase cancellation - which is the stuff that kills your sound.



An inexpensive, and moveable option for diffusors are wooden slanted doors.

check here
http://www.mhsoft.nl/Diffusor.asp
http://www.mhsoft.nl/Diffusor2.asp
http://www.mhsoft.nl/DiffusorCalculator.html

I appreciate this, Dan...will try to sketch today...but basic dimensions are 27x17x8 (for the main room). The DAW desk is caddycorner in a corner...3ft from the wall on the tips...good 5 behind the speakers(middle of desk).

Vinyl on concrete floors. Wood panelling on all walls. Gotta love the 60s.

The amp "chamber" is 17x3.5...not sure on the ceiling-it may be a little different. I do have plans for it...to completely deaden one end, hang a heavy curtain, and then bass trap it as best. My thought is, that that will give me a dead vocal room, keep direct reflections out of the amp close mic, and allow me to open the curtain and put a second mic in there for chamber style verb...cause, did I mention it's all concrete block?

That chamber won't help for acoustic gtr, though...it's really too narrow to comfortably sit with any kind of mics in fron of you.

Sketch as soon as I get a few minutes to figure out what app I can draw in...

OK. Here's the rough sketch...with and without "stuff":





Dan...looking at your pictures--is that not for a mixing room? I mean, I get that in theory the room affects my mix, but isn't the main issue you're hearing is what's being canceled before hitting the mic? Is that little bit of foam behind the speakers in a room this size gonna matter when I'm in the middle of the room with acoustic in hand?

Oh yeah...since you're not inside my brain--the arrows indicate the direction speaker point.

Is that little bit of foam behind the speakers in a room this size gonna matter when I'm in the middle of the room with acoustic in hand?

Well, not just that paneling, but all the treatment you'll do on four walls. Yes, it makes a big difference in the overall sound of the room - not only when you're monitoring and mixing, but also recording with mics.

Pop, I've got more to add. That's just as far as I got last night before.

All of this is for an all-purpose single room in which you're both recording as well as mixing.

Dan, mind If I throw out a couple questions?

If the back wall panels start 3' off the floor and the tweeter height is 48" off the floor then that makes the bottom of the panels about level with the bottom of the monitors, right? Why is this? Wouldn't it be better if the panels were vertically centered behind the monitor, e.g. starting 2' off the floor?

If there's a Sub under the desk does this change the layout?

Thank you Thank you Thank you for doing this thread. I need it and am at the stage to treat my room. Did I say thank you?

17' by 27' with an amp room and a stair well to double as bass traps. I'm getting jealous!

Hey Pop, why the DAW in the corner? Bass build up, early reflection, mud city. It would seem to mean a lot of added effort to get things sounding right.

One of my thoughts when I moved in...there is no "back wall" and no immediate slap in the mix seat due to their not being a "front/back wall" like there would be in smaller bed room.

The closest "back" wall would be the ones with guitars hung. They're hung with about 6" in between over the entire length of the wall. they of course vary in size an depth.

So...it's not that I've not put thought into this...albeit, the thought may be completely wrong, but...I CAN move the desk straight on the wall opposite the guitars. The Keyboards is a two teir stand with a monitor mounted above it. But, I haven't gone to look for an LCD yet, so I have a little CRT sitting on a rack to the side right now. I certainly want to have everything where it should be before mounting that...but, that may prove challenging to the "side wall" treatment. And there is no second "side wall"...

quote:

Hey Pop, why the DAW in the corner? Bass build up, early reflection, mud city.

I think my last post explained my thoughts...wrong as they may be. Electrically, it can't be on the wall where the guitars hang. I'd rather it be on that end of the room, leaving the other end for listening.

So, it's either on the wall where the keys are (reversing the key station and DAW)...or flat on the wall opposite guitars--but, it seems to me that would cause weirdness since there would be a direct slap on the right side, and NONE on the left...I figured caddy corner at least the slap would be both indirect and equal.

You could put your DAW desk in front of the wall with the amp chamber. This would make your back wall the farthest away from the mix position, and that is usually better, as the reflections are later. You may have to move the guitars to facilitate putting up absorption on the side walls for a reflection free zone.

Like Dot said you need 4' high by 6'-8' wide on the wall behind the DAW desk. I would put the same absorption as a "cloud" hung from the ceiling over the DAW desk. I would also do 4' high by 4' wide on the side walls by your monitors. The way to determine where to put the side absorbers, and cloud overhead, is to sit in the mix position and have someone take a mirror and hold it on the side wall, or ceiling. When you can see the monitor speaker in the mirror, that is where to center your absorber.

This is a good start to a good mix station.

Bass traps in all four corners and maybe some of those bi-fold doors on the back wall and you're pretty good.

I made my own absorbers from 2" rigid fiberglass covered with fabric, and my own bass traps, too with thicker 5" and wooden frames. I have 4 of the 2'x 4' x 2" thick absorbers on stands for use as portable gobos. Put them around a vocalist and it makes a huge difference in any room.

If you are handy, that is a lot cheaper way to go and a lot of people think more effective than foam.

just my 2¢

Good thread. I would move the daw where the keys are and face the wall instead of the corner. Sure there may be a big slap right there but a slap is easier to treat than a resonant corner. Absorption behind the monitors, to the sides and a cloud above is the best place to start. You would be suprised how much difference a cloud makes. Imaging becomes MUCH better when there isn't a 10ms delay on everything from the ceiling reflection.

Fiberglass absorbers do work best and can be cheaper than foam of the same thickness. I'd use 4" thickness if you can because the thicker the absorber the lower the frequency absorbed.

I think Dot suggested a 3' hight simply because the reflections below 3' would be trapped behind the desk anyway.

Nick Fournier

I heard your new mp3, pop. I think it's a gnarly tune and the recording sounds totally rad... The guitar solo is super bitchin, dude... For now on I'm going to call you Yngwie Ray Vaughnn, cool?

I do hear the boxyness Dan is talking about though...

The lead vocal is sooo clean. If it was me I'd try to EQ some grit and compress some sheen on it... But I realize you are more into Hall and Oates than Audioslave, so to each his own.

It doesn't sound bad by any stretch, to me.

I did do a double-take on your lyrics though... For a second I thought you said...

"Like a crack head on the sidewalk..."



-Dusty

I just picked up 10 2'X 4' sheets of 2 inch thick rigid fiberglass yesterday and might have to get more as I would like some portable bariers as well.

I need to paint the room before I arrange things and my wife insists that I bring her a fabric sample for approval before I buy a ton for panel covering.

I stacked raw fiberglass sheets around the room today and it inspired me to get cracking with the room transformation.

quote:

I do hear the boxyness Dan is talking about though...

In something besides the electric gtrs?

I realized when I did it the room was an issue with them...but it's not the room the studio is in -they were done in the little closet/chamber/concrete room...I've sat with the dry vocals, and I just don't hear an issue.

I'm still blown away by people not digging the vocal. I was looking at what kind of organs I'd have to sell to buy that mic I love that sound so much...I've gone back to the 87ai tracks and they sound weird and peaky like a 57 in comparison. I wonder if the closer I get to the sound I'm looking for the less people will dig it across the board...like there's underlying reasons why Jonatha Brooke and Maia Sharp and kindred don't sell.

And guys...the "corner"? I'm fully willing to move stuff and treat as a "whole", but putting the focus on the behind the monitors space...it's treating the mixing space, and frankly--me do good with mixing. Dan brings up the problem of the mic'd tracks...frequencies not making the mics for cancellation...it doesn't matter one hill of beans where my DAW is to fix the "issue at hand".

Again...I'm willing to rearrange for the total treatment, but if your main concern is where I've placed the DAW, I think you're missing the issue.

I'm beginning to think that the best thing to do is treat the little 13x4 for amps and vocals...and get some kind of portable diffussor/baffle type thing to section off an area to record ac gtr.

How come no one's mentioned the ceiling? It really seems to me, that if parallel surfaces are the issue...aren't the two MOST parallel, and in this room, the closest together, the biggest issue? They're 8 feet a part, and evenly parallel throughout...even if I place everything in the room all squared up, the second closest parallel surface is 17'--and they ALL have things hung, or CD shelves...or something to break them up...

quote:

And guys...the "corner"? I'm fully willing to move stuff and treat as a "whole", but putting the focus on the behind the monitors space...it's treating the mixing space, and frankly--me do good with mixing. Dan brings up the problem of the mic'd tracks...frequencies not making the mics for cancellation...it doesn't matter one hill of beans where my DAW is to fix the "issue at hand".

It does if it makes it harder to hear the flaws in the mix or makes getting the good mix more work. For example, are the vocal issues because its what it takes to get them sounding good in a challenged space? Besides, you need to treat the hell out of that corner for tracking. You may as well get the mix station out of the way!