I play bluegrass upright bass. When I started attending jams, I felt a little left out, because just playing the rhythm and not singing, it was hard to lead a song when it came your turn. (In jams, usually the players sit in a circle, and take turns choosing and leading which song they play/sing.) I also have a pretty low opinion of my voice. But with not all that much practice, I was able to learn to sing and play at the same time. At first I tended to sing pretty much in lockstep with the rhythm I was playing. But now, I’m pretty much able to segregate the 2.
I’m by no means virtuosic - tho I am exceptionally solid. The way it feels to me as a bassplayer is - the beat is always there. I assume drummers feel the same. But whether I’m playing a busy or simple line, straight, syncopated, or crooked, a huge part of my being is aware of when the 1 beat is coming around. It is so elemental and essential, it almost becomes subcnscious. Once you have that rhythm awareness ingrained, it is easier to do other things at the same time. Does that make sense?
Singing is just layering a different pattern on top/ My biggest problem with singing is remembering the words.
But not everyone can do it. I was taking lessons a while back and ,y instructor - an amazing bassist - said he just couldn’t sing and play at the same time.
Talking is a bit of a different beast. In jams, it is not uncommon for someone to come up and ask you a question, or start a conversation. There are some songs in which I can hold up my end, others in which I can’t. Or I choose the part of the song where I’m able to talk - almost as though I’m talking in between breaths. Does that make sense?
If we are talking about Beatles’ basslines, we have to distinguish between Paul I and Paul II.
Lotta fun basslines, but nothing too difficult, as most of it is pretty poppy and stays within a basic beat.
Geddy Lee, on the other hand, is pretty amazing, to be able to sing, play bass, and foot pedals on some of Rush’s complex songs.