When I am rehearsing with my pianist I never use an amp. I also attend a semi-regular jam with a tenor sax player and a pianist; and I never bring my amp. In both cases the pianists are playing a baby grand. I don't have problem being heard, although I also dig in. In the bluegrass trio I perform with I also go "sans amp" for our rehearsals. That being said, I'm playing a carved bass that's fairly loud.
However, I would not attempt a live performance without an amp, especially if there is a drummer involved. There is an interesting interview in All About Jazz with Buell Neidlinger where the topic of playing without amplification is discussed. He also mentions the hazards of having to compete with loud drummers (which is the number one reason for using an amo IMHO).
However, I would not attempt a live performance without an amp, especially if there is a drummer involved. There is an interesting interview in All About Jazz with Buell Neidlinger where the topic of playing without amplification is discussed. He also mentions the hazards of having to compete with loud drummers (which is the number one reason for using an amo IMHO).