The parts of this tutorial are designed to be read in sequence, not individually.
To begin: an anecdote.
I started making music with Impulse Tracker. After a few years of gaining decidedly un-professional results with that, I moved onto Buzz. Yippee! Effects! I happily threw my sounds into a ton of reverbs, filters, delays, distortions, phasers and so on. In some ways, of course, this was an improvement. My sounds at least had a bit of depth and character. But somehow the real fundamental problem, an "unprofessional" sound, was still there. My tracks sounded weak, thin, and simply a lot quieter than professional stuff; the mixes always sounded wonky, elements not really fitting with each other.
Slowly I came to realise the problem. I was not really using, nor even being aware of, any EQ or compression. After all, they were both a bit scary, I didnt really understand them, and besides - they were boring, compared to my funky range of drastic FX processing. Silly me. I should have realised that...
Think of it this way. You are building a house. Exciting things like flangers and filter-delays are like the designer purple wallpaper or expensive thick-pile carpet. They make your house look welcoming, or fashionable, or comfortable to live in. EQ and compression on the other are making sure the bricks are mortared together and the walls are strong enough to support a roof. And at the end of the day - sure, your designer wallpaper may be lovely, but if the kitchen has collapsed into rubble and the bedroom door is only three inches wide, your house wont be much cop.
My mistake, and I think the mistake made by many learning producers, is to be tempted by the more exciting task of choosing the colour scheme and leather sofas, when my walls could be knocked down by a sneeze and my roof is made of paper. Get the fundamentals sorted first! Otherwise the frilly stuff actually just gets in your way and makes it harder to even work out what your problems are!
Hence this tutorial.
Now I could simply do a lightning quick tutorial on compression - I could say, for example, "for basslines it's best to compress at a ratio of 3:1, threshold -6db" or whatever. (Thats a totally fictional example by the way). But this is only so much use. Of course, I encountered a lot of advice and information about EQ and compression while I learnt. But I know that I never began feeling truly confident in such engineering matters, never really felt I understood any of it, until I put all the pieces together, joined the dots, and worked out that these 2 subjects, and so much more, are all deeply inter-related. So, it is my ambitious aim to map out this whole territory. I present not a strictly practical tutorial, but rather a way of thinking, which I personally found led to a greater understanding, which in turn had many practical benefits.
My central concept is that producers in the digital domain are effectively working inside a box. The starting point will be to define this box, by exploring a few fundamental concepts and limitations of digital audio. Next, I shall investigate each 'dimension' of the box in turn, covering first EQ, then compression. Finally I shall put both of them together, and in doing so, unleash the awesome power of multiband compression.
A word of warning. I have no qualifications. I dont know the difference between dBu and dBv. I dont understand Fast Fourier Transforms. So if you want rock-solid theory and maths, you may be let down. I aim instead to explain the basic concepts, such as they are useful to the practical matter of producing dance music. Naturally, being dnbscene.com, this will relate to drumnbass, but it relates just as well to any form of dance music. Most of my experience lately has been making 4/4. In fact, it pretty much relates to any kind of music whatsoever, although you wouldnt want to treat a folk ensemble recording in the same savage fashion you can get away with in techstep.
Anyway - enough excuses and disclaimers... Lets discover our box (no sniggering at the back please)...