letter

B

A "lip-activated" sound. This generally makes it mildly pleasurable and endows it with a directional "neutrality,"  propelling sound out or pushing it back in depending on what precedes and/or follows it..

 "bill," "Bill"

A

The "short" or flat "a" sound, more or less the noise the doctor asks you to make during your throat exam, usually functions as a simple or neutral connector for other letters and their sounds. Sometimes, though, it's "flatness" can serve to help emphasize or modify the effects of adacent letters. Some examples are shown below.

abandon