Nice chunky analogue square bass from a korg mono poly, with a slow descending resonant cut-off. it has been overdriven.
Bit more raspy. For utter filth I suggest you run this from your sampler, into a reverb with low wet/dry ...
Driven reece bass, recorded in C, cycled (with loop points)
Another Korg Mono Poly sample. The distortion introduces some high frequencies, as does the resonance,
Another Square, this time with a little inverted filter envelope.