Input buffer on dig.amps

Whats this do what amps do and do not use this,thanks
I'm not an expert, but have been looking at buffers. The primary purpose of buffers is often to get better impedance matches among sources/preamps/amps.

Take a look at the the Burson Buffer or the Audio Horizons unit advertised here for stand alone units to see what they do. The Burson has a high input impedance and a very low output impedance of less than 50 ohms. It allows sources or preamps with output impedances on the high side to work with amps that have less than large input impedances.

The Wyred ice amps have a jfet buffer. Many traditional SS ampos have jfet input stages, BTW.

A buffer can also add dynamics to a system lacking in dynamics. Obviously, a tube buffer can add some tube warmth.
I have an Accustic Arts Tube Reference DAC with an output impedance of 33 ohms. The unit has a bit rough/harsh upper midrange. Would the Burson help to ameliorate this?