Do I have "PRAT"??
- Thread starter 62sunbeam
- Start date
Thanks John!
Read that thread the quote comes out of and the poster never fully explains anything relating to the quote in a detailed manner. No supporting evidence or clarification. He doesn't like heavy platters I've learned though. I'm tracking down additional links as well. This was from another person in the thread which touches on some of the conundrum I think:
"Oh yes, TT do vary in sound - though I cannot think of one high end example that is totally lifeless (can you?) or where proper matching of tonearm and cartridge does not make a large improvement. But my descriptors are more of soundstaging, bass taughtness, high end airiness, natural midrange, dynamics, interior detail retreval, etc. I do not like toe-tap factors to play a major role as they are more mood dependent than a true characteristic of performance. This is where I place the PRaT concept - unverifiable and psychoacoustic in nature - absent or present in any turntable pending the mindset of the listner.
I will say that all, well engineered, high end turntables, once set up properly are capable of allowing the the music to come through with the same pace rhythm and timing to the extent the rest of the system is able to resolve it. The sonic differences - minute sonic differences - that may be present are indicative of the degree the design is successful. Any major sonic differences that are present is representative of the TT not functioning properly or indicates the TT is poorly designed/executed."
Pio1980
AK Member
It's good for adding mass and shifting resonance freqs downward, can also damp if applied properly toward that end.
I had included the link along with the quote up in post #92. Here it is again:
http://db.audioasylum.com/mhtml/m.html?forum=vinyl&n=104413
Here's another thread with some interesting comments, particularly in the "I'm always in denial" sub-topic:
http://db.audioasylum.com/mhtml/m.html?forum=vinyl&n=17174
I think if you follow his links to posts describing the Well Tempered Tonearm and the Oracle turntable that you will get some further clarification. Also, the "I'm always in denial" sub-topic in the other thread I provided a link to has some interesting descriptions of the Roksan, Rega, and Linn designs and their effect on temporal performance parameters.
And what supporting evidence or clarification do you offer for that statement?
Thanks I've been in there already.
"First off,you are making a supposition that absolute damping is a good thing. My contention is that isolation form structural and airbourne disturbances is good but that large differentials of resonant energy levels between subcomponents is bad. A more balanced approach is need to preserve the delicacies required for the preservation of "micro-dynamics" and "micro-timing" cues.One can get major gains thru resonance reduction but in practical terms ,cannot completely avoid them. If you have an energy sink such as a high mass platter or clamp then the behavior of the reactive energy from the tracing of information in the groove will be drawn away from the recording(Some of this reactive energy is actual signal information in the form of leading edges). In turn the pickup and record will exhibit modal behaviors counter to each other promoting further losses."
:scratch2: Honestly seems like more nonsense to me. That dang platter mass sucking ("drawn away from the recording") the info in the grooves? To do that it would have to impact the stylus in the groove. Or the platters own resonance would have to be such that it would "color" or vibrate enough to impact in the bandwidth the system is capable of producing.
Maybe if he tried measuring the actual resonant energy generated and propagation factors of the materials involved and the frequency and intensity in various frequencies in each case and could correlate the supposed observation he'd be making more sense.
I'll keep reading; later though, I'm taking a break to listen to music.
michaelhigh
mind's eye music
5/4.
I don't believe you'll find any measurements in the threads in that other hobby forum. I don't think they're needed for the reasoning to make sense and would argue that the statements are rational conjecture rather than "nonsense."
In this thread, various people have stated that they don't know what "PRaT" is or that they don't see how a component such as a turntable can affect time-related performance parameters; some have said that it's just a made-up term that has no meaning or purpose other than marketing. The various statements, obervations, and links I've provided are not offered as objective proof of a position or of a particular product's abilities, but simply as definitions and possible reasons how differences in design can affect what we hear.
Different writers, reviewers, and manufacturers, some of whom I've quoted or provided links to, hear definite differences between components with respect to time-related parameters such as pace, rhythm, and timing. It's quite apparent that many others don't hear those kinds of differences. The Mark Wheeler article gave some possible reasons for this, as did Flavio81 when he said that non time-aligned multi-way speakers can mess with timing. In my experience, adding subwoofers to a system can also wreak havoc with a system's ability to preserve and communicate the time-related aspects of music.
Hwirt noted that other components affect PRaT, too. This is not a new idea, of course. Going back to a 1987 issue of HiFi Heretic, they reviewed over the course of a few issues some moving magnet cartridges, including the Grace F9E Super, TATA RP70, Arcam P77, and Linn K9. One of their comments was, "In terms of rhythmic progression and pace, the K9 is the best moving magnet of all." Differences in this aspect of performance were also noted in their reviews of various preamps. When people don't hear differences in PRaT between different components, perhaps other parts of their system are masking what might be there.
Martin Colloms and Mark Wheeler both noted how difficult it is to find components or put together systems that do everything well (e.g., Wheeler's comment, "now I demand timbre, tonal accuracy and low colouration as well as PRaT. Tough. The search for the turntable that does both is still on."), and in choosing and building our systems, it is often necessary to compromise one aspect of performance to gain another aspect that we also value. In the Martin Colloms article I linked to, he wrote, "It's ironic that you can have an extended bandwidth, or high sound levels, or great stereo imaging, or very low coloration, or powerful, low-distortion bass, or several worthy combinations of these, yet rarely can you obtain these with a coherent, focused combination of natural dynamics, pace, and rhythm."
gusten
Addicted Member
I sure hope it´s not mandatory to believe in a made up catch phrase. Because this I don´t, there are other made up catch phrases in this wonderful world of audio that I also don´t believe in. I guess I can never become an audiophile, and that´s fine with me.
What I do believe in is physics, or as with TTs, mechanics. I believe if you are a competent designer, measuring is nearly enough, listening will just be a confirmation what you already know about how it will sound, in principle.
By this I mean measuring what matters, which you do if you are a designer, at least if you are a good one.
gusten
What I do believe in is physics, or as with TTs, mechanics. I believe if you are a competent designer, measuring is nearly enough, listening will just be a confirmation what you already know about how it will sound, in principle.
By this I mean measuring what matters, which you do if you are a designer, at least if you are a good one.
gusten
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I guess that is why all gear has sounded pretty well the same for the last 40 years or so, huh?
Brett a
~◦●○o0o○●◦~
All words and phrases are made up; including every one you're reading here. These words I'm typing (I hope) are successfully pointing to things; concepts, thoughts, feelings, phenomena.
So what is it about PRaT, among every other made-up word, that holds it in some status "other", or "nonsense"?
Yes, and it's impressive the amount of mental and emotional energy some will expend, not in trying to understand or believe something, but instead in trying to convince people they are foolish or wrong.
Good post!
Must have been a lot of poor designers who did the equipment at the Fest this weekend. All the equipment sounded different, and there were some clear examples of PRaT, if you were willing to listen to them. Again, you have to be willing to listen...
marcmorin
RIP 1953-2020
Mine only moved 40 yards off the face of my Hogan Radial 9 Iron. Had a funny rhythm during flight. Hardly any backspin.
I'm confused as to when never actually doing any field observation became objective.
flavio81
Turntable technician
The words you are using are made-up, but the meaning of most of these words or expressions ("made up", "including", "every one", "typing") is clear to every one of us. Thus yours is a post that clearly communicates its message. The meaning of every word is conventional.
On the other hand, you can clearly see that in the previous posts, people have used implied at least 3 different and distinct understandings of what "PRaT" is. The meaning is not conventional because few follow the convention.
So, as i said before, that's my problem with the term: People use it liberally for anything that means to "sound good" to them. We might as well use "great toe-tapping potential" instead!
You and me both, brother.
flavio81
Turntable technician
Fully agree. A really good turntable designer knows what to do to create a great sounding turntable, and knows what to measure and check for to ensure all is going as planned.
This doesn't mean that "all gear has sounded pretty well the same for the last 40 years or so" which would be a very inane thing to say.
There are bad, average, good, great turntables, but what makes a great one from an average one is not black magic, and has direct relationship with its design and execution.
So which are the great ones?
What is interesting how little energy it takes to read the Ken Lyons posts and understand what hairshirt theories are. Bigger bearings produce more noise, the flexing of a Rega's motor mounts somehow helps with its abilities for example. The "denial" quote above is a perfect example. How about:
"The Well Tempered is a VERY musical device but it does things to note attack and decay as well as subtle micro timing cues that are the antithesis of good PRAT. "
"BTW- I am of the conviction that there is some point that high mass platter design CAN work .It must be sufficiently high enuf that inertia will completely overcome any frictional forces that are at work on the system.I can only surmise at what point that comes but it must be in excess of the 8-12 plus pounds for a typical turntable platter(based soley on personal experiences in the medium-high mass designs that occupy much of the conventional turntable market). This approach is still unfavorable to me in that the higher mass is then in need of a more massive and therefore inherently noisier bearing to support it, barring some clever and unconventional bearing concept.Here I foresee the cure being potentially more damaging than the initial problem. "
I sure things did sound wonderful much of it pratful. No argument from me on that.
Did someone declare they wouldn't listen:scratch2: