We've all been exposed to some degree of metal I assume and, as you may know, a lot of metal sounds like **** (in a good, maybe even great way). Between the screaming, violent lyrics, distorted strings, and aggressive drumming, a lot of people have come to generalize metal as the Devil's music (kind of like the tri-tone back hundreds of years ago. See Diabolus in Musica for more on that). Whether or not anybody agrees with this is not my concern. Rather, I want to look at blast beats, because they are abrasive to most, and I want to discuss a particularly abrasive blast beat I came up with the other day.
If you were referred here from my polyrhythm thread, you should find this especially enjoyable to let your brain play with. If you're the best, the man, a professional, daring, or really full of yourself, feel free to skip ahead to the bottom.
Ok so the premise of this blast beat is the polyrhythm 5:4. When I teach somebody 5:4, I map things out in a measure of 5/4 time with beats every 4 and every 5 17th notes. Together this sounds like this: 1, 2e, 3+4, a5, and then they come together again on beat 1. If you take your hands/sticks and try 5:4 you will, inevitably, find that your brain can only process the relationship between the rhythms so fast. After that, it becomes difficult to keep things sounding and feeling clean. Some are faster than others, but that isn't my concern here.
What I found in making this blast beat was that, to play it at speed, it is impossible to feel the relationship between the 5 and 4 (we're looking at around 600+ bpm as a requirement to truly feel the relationship, at least when you map it out as I have above). If you can feel this relationship at such a speed then you are a champion. But you can't so I won't bother patting anybody on the back.
Because I too am human, rather than map things out in the context of 4 16th and 5 16th length beats played at lightspeed, I took a different approach.
What I did was take the quarter notes (IE every 4 16ths) and the beats of 5 16ths' duration and threw them away. Instead, I gave myself a quarter note pulse (142 is nice for anybody who wants to try this) and tried to play 16ths with my feet (strait 16ths, not one note every 4 or 5 16ths), and quintuplets in my hands. Feeling the polyrhythmic relationship between my feet and hands at this speed is virtually impossible, so what I did instead, was focus on the quarter where they come together (use a metronome if you want to hear a downbeat, because your limbs will be tied up). If you can put 16ths on double bass on auto-pilot, redirect your brain to the quarter pulse and just focus on playing quintuplets with your hands in time, and pay attention to how things land together.
The bottom that you may or may not have skipped ahead to
Ok so here is how this fun little beat goes. At anywhere between 80 and 200 bpm, lay down some double bass 16th. Flip the switch in your brain so that they may go on auto-pilot. Then, focusing on the quarter note pulse, add quintuplets alternating rapidly between the snare and ride cymbal. If you're doin it rite, the upbeat should have a snare note, and the down beat should have a cymbal note (or vice versa). Each quarter note's length should contain 4 bass drum kicks and 5 stick hits. Not unlike traditional blast beats, the rapid alternation between the snare and ride cymbal should sound abrasive, however this abrasion is intensified by the extremely fast polyrhythmic relationship between your hands and feet (don't be scared by the words "extremely fast." Not much speed is actually required to play this at lower bpm).
See here for the beat written out (on a side note, I can't upload any type of file here, which is saddening to me. If someone can help, I'd be appreciative): View image: Blast Beat
EDIT: I screwed up writing the beat in finale. Forget about those triangle shaped noteheads and just pretend that they are snare beats.