Here's what it sounds like when you use a bass as a rhythm guitar, lead guitar, & bass together

Does anyone else recall the original version of Big Bottom by Spinal Tap?

Oh, I actually just remembered this instrumental cover of Secondary Modern (the Elvis Costello & The Attractions song) in which I actually played the melody (sung vocally on the original) on a Fender Jazz Bass, though it trades off with the guitar for the bridge section and begins playing a counterpoint line at that point, then resumes playing the melody. I swear I am not just selfishly bumping the thread, I actually literally just remembered that I recorded this last year and it pertains to the discussion.

Jaycat, are you currently taking any kind of lessons, formal or informal? If you already play guitar and mandolin, that means you should have a good intuitive musical sense; physically, though, the instruments are so different from bass, the muscle memory involved is totally different and because of the much thicker and longer strings, you really have to use your fingers in a different way, you have to attack the strings with the meaty part of your fingers, you have to ‘dig in’ a lot more to get a good powerful tone on the strings…i guess the best way i would put it (and the words literally just now came to me, i never thought about it this way before but the discourse on the different physicality made it occur to me) - the best way i could put it is that the relationship between your right hand and the strings, is more “three dimensional” on bass than on guitar. Because the strings are so much thicker, are farther apart because there are only 4, and the action higher, you can hit them from more angles than the strings of a guitar, and these different angles result in different tonal qualities.