Bass science 101
OK, here's how I did the bass.
First, I used a stock sub-bass sound in Reason's factory sound bank: Dirty South Bass.
I edited the sound a tiny bit as you can see from the shot. It's a fantastic, massive sub-bass sound - if it sounds weedy on your speakers you probably need new monitors to make dubstep. Some monitors won't play this sound at all.
Crucially I set the LFO1 destination to Oscillator 1,2 - this meant I could automate the "whomp-whomp" flutter on the bass to get a recognisable dubstep sound. However, it's important to note that most dubstep producers from Loefah down will tell you to set the LFO destination to the filter to create the classical dubstep bass sound - you should probably experiment with that first. I was lazy and just stuck with the first noise that sounded good.
I then varied the amount and the rate of the LFO manually throughout the song. It took more than ten seconds to set up a control surface to do this, so I just drew it in throughout the track:
I probably spent a total of half an hour editing this LFO automation in a couple of psses over a couple of days. That's really where the dynamics in the track come from. I also switched LFO tempo sync on and off throughout - this makes a radical difference to the sound. One of my pro producer friends says you should always leave it off for spoingy basslines.
You'll notice from the arrangement that the bassline -- well, it isn't really a bassline. It's just a series of very long bass notes on A3. I think there's some weird off-sets on where the note falls versus the measure - can't remember where it ended up, I fiddled with just where the note happened for a couple of hours. It's a seriously minimal track! The new one does a bit more musically.
When it came to the mix I tried to take out everything below 30hz and rolled off most of the top. This was to make space for the kick; I knew there'd be plenty of low end energy in the final pre-master anyway. Then I compressed it a bit to even it out.
After that, the signal went straight out to Cubase (bypassing Reason's mixer) where I stuck a multiband compressor over it, set to the Bass preset.
There are some bleeps in there too:
They started off as a stock wah-wah gutar sample that's go a slow envelope on it and a big, synced LFO on the Dr REX oscillator. Took ten seconds to do.
And there's that noise as well:
Again, just a stock SH101 noise from the raw waveforms folder with another fast LFO on it, with a lot of fader riding and delay.
There's another syncopated bassline part as well that does some subliminal blips, too.
An important part of the whole sound was that I pre-mastered at 24bit (out of SX) at a very low level, avoiding all clipping -- which resulted in an extremely weedy-sounding file. Then for the purposes of the mp3, I totally cheated and wacked this file back into another SX arrangement with a multi-band compressor over the whole mix set to the very, very nasty "FM Radio" preset, which I edited to make it sound less spitty. It's a horrible thing to do to a waveform but it does make mp3s work a lot better, and I tried to curb its worst excesses, though I don't really know what I'm doing with it. Finally I encoded it with LAME.
So there you are. Dubstep basses are a lot easier than you think and Reason gives you heaps of raw material to work with. It's the arrangements that take the time to get right.
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