For once, this will be a short article. Below, I've posted four simple bass instruments. I've been generating samples to use in Renoise (which, by the way, is available for Linux); I wanted a set of simple, but powerful bass sounds -- completely clean, and hugging the 16 bit maximum.
Csound to the rescue!
In theory, these instruments could be played as more than just bass. For each instrument, I generated two octaves of the notes C, Eb, Gb, and A, starting with five stringer C (the C three octaves below middle C, pch 5.00). Loaded into a tracker, each sample can also be modded to its neighbors: the C sample can be the basis for the notes B and C#. In this way, it's possible to generate two full octaves of notes from a basis set of just 8.
The basses below are the simplest I could make. I've set the demo orchestra for each to four stringer E (pch 5.04). Consider the 'pluck' version to be the model; the other three are variations.
Probably the best sounds came from repluck and wgpluck, which allow the 'pickup position' to be set; I simulated a double pickup J-bass sound, with the bridge running a little hotter than the neck.
For the wterrain instrument, I tried getting the famous Jaco 'mwah' effect. Close, but no cigar. Still interesting, though.