PRat: a DAC or transport thing?


Hi folks, I would like to know if PRaT is more related to DAC or transport? Could I improve PRaT by using a contemporary top flight transport (instead of the 10 year old Accuphase DP-90)? Thank you. Btw, I'm using the matching Accuphase DC-91 DAC.

Chris
dazzdax
As Judge Potter Stewart said of pornography, "I shall not today attempt further to define the kinds of material I understand to be embraced . . . but I know it when I see it . . . "

PRAT is pretty much in this same elusive category. It's also a kind of holy grail that's only revealed once a number of problems have been resolved through both additive and subtractive effects. Once other problems are resolved, the most stubborn gating factor for most systems is probably the DAC/transport clock. Nuances of timing, pitch, and timbre are revealed in the reduction of treble smear and bass wooliness caused by even low levels of jitter. It's much easier to get PRAT from a vinyl source. I've had four different clocks in my CDP, as well as many other mods, and only the best clock will get your foot tapping.

Dave
sean, i proably ignore this aspect of recorded music, as i tend to concentradte on timbre and tonal balance.

i believe it is a term which applies only to recorded music.

i tend to think in terms of live music and try to relate to recorded music as if it were live.
Gregm: Yes, i would venture to say that phase linearity is a good portion of what contributes to "PRAT". As Dazzdax also added, an added bit of "warmth" can sometimes help this out too. As Dgarretson also pointed out, when things are right, your toes are tapping. The system is singing and you can't help but get into the groove. This is a natural reaction to music, whether it is live or recorded.

In that respect, i have to ask Mrtennis how often he finds himself wanting to tap his toes, bang on drums or play air guitar when listening to various systems / components? After all, the more intensely that the music draws you in, the more of the "you are there" effect you experience. You are no longer just hearing recorded notes, but jamming tunes to the extent thatyou can easily visual and share in the energy of the performers playing their hearts out. Sean
>
Mrtennis sez
i tend to concentradte on timbre and tonal balance.
Ideally, in a well set up system, you would NOT have to concentrate on anything -- but the music.
Of course, even in such a well set up system I believe there is an individual "minimum resolution" level which allows to concentrate on music rather than be distracted by reproduction anomalies and artefacts. It's that dividing line that must be crossed by system performance level and set-up level -- and we can enjoy the music: this level obviously differs from one to another. Also the preference points differ; you express your focus points as timbre and tonal balance. I am very partial to "dynamics" (i.e. changes in amplitude) and linear phase & resolution: for me, the thin dividing line between listening to a musical artifact and listening to music is there.
FWIW, in my limited experience I have come to believe that the sense of PRAT has more to do with any components ability the recreate the initial or leading edge of the note, get the rise time right and you've got half of the battle won. Then get the decay time right and you've got the ability to sense PRAT, assuming its on the recording in the first place.

Now, get that signal thru all your stuff undistorted (perfectly resolved, without hyped detail common to much that is called 'resolved') and you've got great imaging (potential) as well. Every thing in the system contributes to this effect but probably the last place I would think to look for loss of PRAT otherwise available would be in a CDP/Transport-Dac unless it had tubes. JMHO.