Amp "timing" ?

Amp timing can cause speaker plodding. When this happens, advance amp timing gradually until you hear PRAT, then back off a degree or so. 

Sound is essentially changes in air pressure over time so yes sound is directly time based and there are many factors in an amplifier (and speakers) that together can result in timing differences and differences in sound. A high degree of detail, imaging and sound stage in a good high end setup is a good indicator that things are going well in regards to timing.

Lets not even get into the timing issues that may also be in the recording to start with to similar ill effect. You just have to live with those and try not to make things worse.

Btw you can easily set this using track 3 of Pink Floyd Dark Side of the Moon.

A good musician will play on, behind, or ahead of the beat, resulting in the "feel" of a musical presentation...that’s timing, and if my hifi rig does any of those things on its own I’ll assume I’ve lost my mind.

@wolf_garcia: +1