What exactly is PRaT???

Thanks @soix , this is a bit of a mystery to me too, though I don’t doubt that it exists. Maybe it goes by other names, or feelings, when everything has that just right feeling. 

@Soix - PRaT is what you get when you engineer a sound that is harmonically lean and emphasises the leading edge of the dynamic envelope. Being a drummer, unless you are a really bad drummer (which I'm sure you aren't), I'm no doubt you are perfectly capable of hearing this if you listen to the kinds of system's favoured by "PRaT" lovers. The term started to be used in the 1980's when Linn/Naim orthodoxy was at it's height in the UK. It started to fall away when a broader range of equipment started to be popular - most of it coming from the USA.

Away from the quasi cultist aspects of this, there is an underlying germ of truth in the sense that some components can be more coherent than others. However, that coherence is exhibited in the reproduction being full frequency and having a natural musical flow i.e. the system is expressing the recording and not superimposing a tailored sonic signature on it.

Some guys may be conflating what is baked into/inherent to the track/recording itself (instruments, notes being played, etc) as aome accomplishment of their gear. Such a track may seem to have great prrrrrtttt on all kinds of equipment (because in reality it was Bonham making you feel that way).

Otherwise, and if the same track is compared on different equipment, some technical parameters can be attributed to this perception of prrrrrtttttt. On speakers...the stored energy graph can be an indicator, no huge phase shifts from crossover, etc....low power set is a prrrrttttt killer, etc

This perception also varies greatly from listener to listener and the type of music. Some guys may only listen to some sleepy boring gal whispering slowly for hours to a very slow boring string. There may not even be any percussion involved. Such listeners may not think or need to care about prrrrtttt parameters.

I was a Linn/Naim devotee in the early 80's when my interest in home audio started. My dealer espoused the Linn/Naim credo: Source-first hierarchy, Garbage in/garbage out, single speaker listening rooms, "testing" components by toe tapping and humming the melody, etc. Of course, as my music interests changed, it was hard to hum and toe tap to Schoenberg, but I sort of got what they were saying. 

I just started drum lessons again after taking 50 years off. When I was 13, it was a rock and roll backbeat that I was interested in. Now I want to swing my ride cymbals with dotted 8th's and feel the looser syncopated pulse. My drum teacher believes in the metronome, and also in ditching the metronome so you can feel the rhythm with your body. 

I think that my Linn dealer used PRaT in that way: You'll know it when you feel it, and you'll feel it with us, and not with the other guys. 

I was an art teacher most of my life, and we are always using metaphors and simile to describe the ineffable. I personally think that trying to describe the rhythmic qualities of electronic gear is like that. It points to something that may be important, but it remains out of reach. 

I've always interpreted it as speed and clarity. The attack and decay of notes are distinct and on time. Some speakers excel at this. I'm less clear about what it means for electronics but I assume the electronics play a role in creating that. 

I had a pair of speaker cables that seemed to slow the attack and it felt like notes were actually late in timing and decayed too soon. As soon as I changed cables, that disappeared.