(A Rule of Thumb Guide)
First of all, welcome to Byte-Mix Sound Design.
This is my first guide, and so it may be updated and revised as I find mistakes,
or come up with better explanations.
This guide is geared toward setting up a home/project studio,
and making the most out of the setup.
DISCLAIMER: This is --NOT-- a comprehensive guide. This is strictly what I know from experience, research, listening to other home-studio musicians, and what works for me. This "guide" also assumes you are just starting out in this field.
I: Listening Position
The rule of thumb for setting up your mixing position, is you want your listening point to be 38% the length of the longest wall (a little more than 1/3 of the room). For example, if you have a room that is 15x21, then you'll want your mixing spot to be 7 ft. 11 and 3/4 inches from the back wall and in the center. There are physical and mathematical reasons which go a bit over my head, but for all intents and purposes, this is the "sweet spot" of the room.
Now, the question is where do you put your speakers? Well, for starters, you'll want the physical speakers themselves to form an equilateral triangle with the apex being between your ears. But, how far from your ears should the speakers be? Well, for one thing, you do not want the speakers flat up against the wall. Speakers generally need a bit of breathing room behind them, so let's give them about 2' from the wall. So now They're roughly 6' from your head (a little more considering pythagorean's theorem) so you'll want the same distance between the speakers. The woofers should -not- be at 50% of the room's height, but the tweeters -should- be roughly at your ear level. Now as for where the speakers should face, that should also be toward your head but not facing right at you. Let the point where they face be a little bit behind you. This will help emphasize the stereo image/instrument positions in the mix itself.
Granted, being in a home studio situation, the room many not conform to the standard, and it may be impossible to have everything positioned just so. Still, try to get it close if you can, and make logical sacrifices if you have to. God help you if you get stuck in a small perfectly square room.
II: Room Acoustics
This is probably the first thing you need to worry about. Whether you are recording, or mixing, the room will have a -very- significant impact on what you hear as well as what the microphone hears. You might ask yourself what do I need to make the most out of my room? The simple answer is acoustic treatment. However there are a lot of factors that fit into that simple answer. Why do I need it? What kind of treatment? Material? How much? Position?
Assuming you are working in a standard room with 4 walls, a flat floor and a flat ceiling: when sound is propogated from the speakers, the waves will travel out into the room, hit a surface, reflect off, and come back into your ear from all sorts of directions. These early and late reflections will significantly affect what you hear, and skew the results of anything you're working on. The goal in mixing and mastering is to have your music (the final product) translate nicely to many other rooms and systems. So, if you are working in a room with poor acoustics, anything you get sounding good in that room will likely sound like crap on someone else's system. If your room is relatively neutral, however, then what you get will likely play back nicely on other systems and in other rooms. Even in a poor room (any small rectangular room) you can get decent results if you apply acoustic treatment with some thought.
First and foremost, the most significant problem in smaller rectangular rooms is the bass response, or specifically a hyped bass response. The problem is that bass waves are very very long, and the lower the frequency, the longer the wave. These very large waves have a lot of energy, and these frequencies tend to build up in the corners of the room. Try it: put on any music with a good bit of bass, and slowly walk towards a corner. As you get closer to the corner, the bass will be louder and louder and louder, until you're in the corner where it will dominate everything else in the mix. Not to mention having the walls resonate with it, and have it reverberating back into your ears and influencing what you hear. The best way to get around this is to use a good bass trap.
Note on square rooms: Try to avoid setting up your studio in a room where the wall dimensions are the same (9x9 or 8x8 or 12x12) Square rooms are very poor for mixing and recording. There are mathematical reasons as to why which you can feel free to research yourself. If you cannot avoid it, then use as much treatment as you can without turning it into an anechoic chamber* (more on that below)
A bass trap is desiged to literally trap the wave and prevent it from re-entering the room. Usually they are made with a layer of very dense insulation like Rockwool (aka mineral fiber) They extend from the floor to the celing and sit across a corner. The wave will hit the trap, move through it, have some of the energy transfer to the foam (and then dissipated into heat energy), then move through the air behind the trap, reflect, travel back through the air, and hit the foam again. The key here is the density of the insulative foam. Standard fiber glass or pillows or bulletin board/corkboard do not have the required density to absorb such a huge wave. You'll want to use something with mineral fiber (rockwool) or something similar.
With bass traps in place a very large portion of the troubles with room acoustics will now be under control. However we're not done yet. You've still got issues with the broadband of the frequency spectrum. Usually strategic placement of absorbers and diffusors will eliminate problems in those ranges. You will want plenty of absorbtion behind your speakers, and directly over your head. Possibly a little less to your sides, and a little more behind. The smaller the room you're working in, the -more- treatment you'll be wanting to use. One trick is to have your friend walk around with a mirror along the wall at ear-level. When you see the reflection of a speaker in the mirror from your listening position, that's a spot you'll want to have some absorbtion at. Book cases can work well for both absorbtion and diffusion, and they are common and cheap solutions in the home-studio setting.
*Now, even though more acoustic treatment is better the smaller the room, you do not want to completely cover all your walls, floors, and ceilings with the stuff. What you will end up having is a very "dead" sound, similar to what an anechoic chamber accomplishes. However, mixing in that setting will create a sense of pressure, and it can be very uncomortable and possibly even disorienting. You always want the room to have a little bit of liveliness to it.
Note for vaulted ceilings: They are a good thing in that they won't be parallel with the floor. However, frequencies will tend to collect along the high points, so hanging some absorbtion just under the vault along the ceiling would not be a bad idea.
This section is far far less critical than the first two. Basically, you'll need some equipment to get yourself started: A Digital Audio Workstation, which would run on your PC, and an Audio Interface (soundcard.) There are many, many different DAWs (Digital Audio Workstation) out there. Pro Tools, Cakewalk Sonar, FL Studio, Reaper, Krystal AE, Cubase, etc. etc. Many types of software have their strengths and weaknesses, and it's up to you to figure out what you need based on what you intend to do. Are you going light on recording, but using a lot of VST/Midi? FL Studio fruity edition + Audacity would be a cheap solution for about $100. There are also many many different audio interfaces from low end to high end. M-Audio makes some good quality cheap interfaces, and then there are higher end solutions such as RME and MOTU. It really depends on your budget and your needs. If you need to record a lot of instruments at once, you'll need a mixer, and an interface with as many ins as you have outs. (so if you want to record 8 separate channels, your audio interface will need 8 individual inputs)
It all boils down to budget, and intended application. You do NOT need the super-high-end gear to make quality sounds. It's not about -what- you have, but about -how- you use it. If you learn how to do what you want to on the cheaper budget equipment and software, then it just becomes easier to achieve the same result on the higher-end gear and software.
For some more detailed guides, feel free to have a look here:
And a more in-depth article written by Ethan Winer: