Well, Scroll, I learned that each professional bass player has his or her own unique approach to playing the bass. In my opinion, learning to stand-up and play the bass makes the most sense. If you learn how to play properly while standing, then you can apply the same ability to the process of sitting and playing comfortably, depending on the performance context.
When first learning to play the bass, it is easier to get the feel of it while standing. The bass, as do all of the other string instruments in the violin family, come in student sizes. Most professional players use fractionally smaller sized basses, due to the physical demands of playing the bass. The playing comfort gained from a 7/8 or 3/4 sized, proportionally constructed bass is astronomical! If the bass is too big for the student, this already cumbersome instrument becomes more challenging to master.
Thank you, V. So, the term Stand-Up Bass is what you suggest. I want to add a little more about the design evolution of the bass’s back. The back of the bass sometimes has a flattened section in order to lessen the width of the body of the bass. This was a product of trial and error on the part of bass players/luthiers. Knowing why this model came into existence will assist you in your bass playing-position set-up, whether or not your own bass has this feature.