BLIT stands for "Band-Limited Impulse Train" where "band-limited impulse" is basically a brickwall low-pass kernel and "impulse train" means you put them at regular intervals. If you integrate such an impulse train, you get something resembling a sawtooth wave (well, there's some DC shenanigans to take care of, but that's the basic idea).felis wrote: Mon Jan 10, 2022 1:10 pm If anyone has time, could they give a layman's description of BLIT, BLEP, and BLAM.
We can also just take one of those band-limited impulses and precompute it's integral which is a "Band-Limited stEP" or BLEP for short. This way we can just generate a simple saw-wave and at every jump in the waveform subtract the difference of the simple and band-limited steps, which happens to be exactly the same as the aliasing. This is great when you're trying to do serious analog modelling, because you can just make the oscillator behave in exactly the same way it'd behave in an analog circuit and then just add the BLEPs on top and you've got rid of the aliasing.
If we integrate the BLEP itself again and again we obtain so called "higher order BLEPs" which allow us to construct band-limited piecewise polynomial waveforms of correspondingly higher orders. In particular, the 2nd order BLEP (if we take the actual "step" to be 1st order) is a one-sided Band-Limited rAMP, sometimes called a BLAM or BLAMP (which is most commonly used to construct band-limited triangles).
The technique is not limited to just BLEPs and BLAMPs as it works essentially the same for higher orders too, but since coming up with further acronyms gets tedious, usually at that point you just call it all "higher order BLEPs".
