Microphone Transient Response
A transient is a short duration with a high level peak. Transient response is to the ability of a microphone to respond to these transient peaks. A slow transient response will determine a smooth transition but will lose detail, which a short response will gain in detail but sound harsher. In a certain way, slow responses homogenize transitions and attacks, conferring to them a round, pleasant, warm, and touching sound. Conversely, short responses will make a recording very precise, but harsh, naked, exposed, dry. To a certain extent, the former ones beef up the sound and amalgamate it, while the latter ones make the voice or the instrument sound feeble, isolated, lonely.
The following diagram shows the transient of a dynamic microphone, which is similar to that of ribbon microphones.
As we can see, it's peaks are well rounded up. And indeed, they sound round! The next diagram shows the same transient, but recorded with a condenser microphone.
In this case, there is no rounding. The sound has harsh peaks, which can be easily recognized by our ear. Because of their sensitivity, condenser microphones are well suited for capturing ambient sound. During far recording, the sound produced by the voice or the instruments mixes with the natural reflections of the hall, with the result that it becomes rounded. The far distance compensates and rounds up the transients that, otherwise, would not be acceptable.
We can imagine the transient curve as a series of bits. The more sampling bits we have, and the sharpest and more detailed the transients will be. Lower sampling rates are more imprecise, but round up sound.