A 1977 Ibanez Silver Series 4 string Jazz bass (a Fender knockoff). My first real bass, and the one I always pick up first. I've replaced the chrome hardware with black, put in new pots and a jack, and put in EMG pickups. Black nylon flat-wound strings. It's heavy but I love it.
Second choice 4 string is a Fender jazz bass. First choice 5 string is an Ibanez SRA 555 with half rounds. It has a skinny neck only a little wider than a 4 string, which I really like.