PRat: a DAC or transport thing?

Hello, in theory Mrtennis is right,
however in practice, your 10 yrs old Accuphase transport might
need re-calibration. The main crystal is aging, because of that it could change transport's main clock frequency.
If this change is more than +/-200ppm the rhytm and tempo of music will change. After all sampling frequency (44.1Khz) derived from main clock.

Ahh, Mr. Tennis. You don't understand PRaT, and probably never will until you hear a system that does it well. It is not a matter the speed of a disk, it is a matter of how an entire system reproduces music in a manner that gives a sensation of rythmic tightness, or "pace". It is a very real thing.

Mind you it does come at a cost. Systems that do PRaT well (Naim, Linn) do so somewhat at the expense of other aspects of music reprodution that others may find more important. But to say that there is no such thing because records/CDs spin at the same rate is to completely miss the point. It is even more over simplified (and in error) than saying there is no difference in the sound of cables because they all are transfering the same electronic information from one component to the next.

PRaT and cables all in one message. Next we will have past life regressions and crystal power. Spend your money on something real like room treatments and speakers.

PRAT has to do with both frequency response and transient response. Without reasonable tonal balance, you can't have PRAT. Without reasonable transient response, you can't have PRAT. With lesser degrees of either tonal balance and / or transient response, you get correspondingly lesser degrees of PRAT.

What we hear is SYSTEM dependent, so one has to look at the system as a whole. Having said that, one small leak can sink a large ship if unattended to, so you have to find where the leaks are and attend to them individually. One might find that they have one giant leak or they might have a bunch of smaller leaks spread throughout the entire system.

The question here is, did these two components as you are using them now ever deliver "PRAT" when combined with the other parts of your system in the past? Sean
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if you listen to live unamplified music, the playing exhibits a tempo, and within that structure the individual notes may vary. for example, in 4/4 time, there are 8th notes, quarter notes, etc.

if a composition takes 10 minutes, there is a sense of pace based upon the markings. thus, for example, adagio, presto, etc. .

musicians play can play fast or slow. once it is recorded the tempo is set and the timing is set. if you play a recording on 5 stereo systems, the tempo is still the same and the elapsed time is also the same.

if you are talking about perception, that depends upon the listener.

i think the concept is a construct used by audiophiles but has no value as to communication.

i would like to hear a demonstration of this concept. any suggestions ?