Two terms I don't understand - please explain

Slam = dynamic impact, i.e., how well loud, fast extreme transients are rendered.

Prat (or PRaT) = Pace, Rhythm and Timing -- a component with PRaT gets your toes tapping, let's you hear an feel the drive and pulse of a tune (maybe even puts it there, in some cases, e.g., where a TT spins too fast). Pretty much the same thing as boogie factor.

Roughly, anyway.

Jan, most often slam refers to bass impact. That is you feel the sound waves hitting you rather than just hear the notes being played.

PRAT refers to Pace Rhythm And Timing. This applies to all playback media not just analogue . If a system has poor PRAT it appears slow and lifeless. Good PRAT means that it is alive much as the real event would be.

I will leave to others with more knowledge than I have to explain why we perceive something as having good PRAT.

Phaser's explanation of slam is better than mine. It refers specifically to bass transients.

Great explainations of the generally accepted interpretations of these terms; however, I'd like to point out that the Pace, Rhythm and Timing part of PRaT are misnomers. All but the most seriously flawed systems get these elements of sound reproduction correct.

All but the most grossly out of whack turntable will get pacing (tempo) right. If pacing is right, then rhythm and timing (another word for rhythm) are right.

So what leads to this impresion of better PRaT for one system vs. another, it's the ability to effortlessly reproduce dynamic range, from the very softest to the very loudest, without introducing other undesireable elements (distortion).

I'm a serious musician and we often use dynamics and accents to imply speed and motion. If you don't hear the dynamic change, then the music sounds, lifeless and uninvolving.

PRaT and Slam are the same, IMHO, except that Slam refers to bass dynamic performance.

PRaT seems to be a permanent part of our lexicon, but I think misunderstanding it might do more harm than good. I'd like to see it banished, but I'm only one vote.

In those instances where Pace is flawed, it's usually the fault of the TT or the TT's power supply variability, causing wow and flutter or speed inaccuracy. Guess what, when you fix these things you get better "slam". Applying this to other components, where electrons flow in nanoseconds is folly, IMHO.

DAve

Pace, Rhythm and Timing are nice, but I'll take Noilly Prat any day--it mixes well with gin at about 1 to 8 and makes everything sound better. ;)