What exactly is PRaT???

@bryhifi 

Great comments. I never thought of it that way. Good analogy. 
 

I just want to point out again that PRaT is probably the most difficult parameter to sense. I know many folks that do not know how to detect it yet. But with thought and careful listening you probably will eventually. And that is likely to be a real epiphany.

@soix 

I thought I understood the concept to mean musical pace, rhythm and timing.  However I have come to think of it as more than that- explanation in a minute. 

A system with a lack of PRAT sounds mono level- at a micro dynamic level, minor swings in volume, not opposed to big swings in level which is different- meaning all sounds tend to be banded together in a limited micro bandwidth and when listening tends to sound flat and unexciting, like the music just sits there by comparison.  

However once I acquired fast speakers and a fast class A amplifier PRAT took on a whole new meaning for me.  It was no longer just about rapid transitions in micro dynamics, it also became about musical element separation and audible distinction.  Musical elements became much more on their own in space, relative volume level and distinction / clarity.  It was as if each voice or instrument had its own physical channel and speaker.  Everything stood out more on its own and quite amazing.  The music and sound had much more contrast which let the pace and rhythm of each instrument become clearly audible.  A drum track in the background was much easier to follow and focus on because it was much more delineated than with a less dynamically capable system which seemed to blend everything together.  

It means the music is vibrant & the musicians are playing together. So the meaning of the song comes through. 

To me, PRaT is a subjective (although not stupid) term.  To me, it refers to how realistic the music sounds, i.e., does it sound like you are there?  Does it give the illusion of a performance right in front of you, with depth, width and proper tone?  Since that is so dependent upon system, synergy, room size and treatment, etc., it can only be subjective.  I never refer to PRaT for that reason — I just say that my system makes me feel that I am there witnessing the performance, wide and deep soundstage, etc.  Those are terms that although they are subjective, they have some general understanding among the audiophile community.

OP…. As the old line goes about jazz… Of you have to ask, you’ll never know….

@soix - not knowing PRaT in audio components may be a blessing - one less thing to detract from the music

I find this interesting.  I'm with soix as I too have difficulty pinning down the understanding of PRaT in audio components.

I understand what is musical drive, but cannot put into words. I understand when orchestra timing is off, but when it focuses music beauty and drive take over.  I get the gist of @atmasphere in that increasing component sonic errors leads away from emotional engagement towards the analytical as we're wired to single out things that don't fit.  

When evaluating components, I do the usual test tracks: own familiar songs, test cd songs, acoustical instrument reproduction, etc. specifically paying attention to voices, piano, violin, bass definition, etc.  When choosing a component, I choose one that "resonates" with me (sounds great top to bottom, pulls me into the music) like Magico, MBL, YG.  Likely PRaT is a subcomponent of "resonates" that I simply haven't isolated separately

As a former musician PRaT never clicked with me in home audio until a full Krell class A system with Thiel CS3.6 cycled through here.  @soix , I can only relate my experiences playing in bands like this.   When everyone is locked in perfect synch with tempo, perfect attack and release, volume and balance, there is an undeniable completeness to the sound of the group.  No early flams, no hangover notes, no smearing of staccato passages, running musical phrasing is in lockstep to the point that every note is heard but none stand out in any way.   The band speaks with one voice.  
I have listened to recordings of myself with excellent musicians and always hear the original performance to some degree or another.  We had a few sessions that were “tic-less” or without error for those non band / drum corps folks understanding of that word.  Tic = timing error.

The combo of class A and phase coherent speakers opened my ears to the most accurate presentation of music I was intimately familiar with.  No smear of any sort.  With that system in place and only speakers rotated through, I became aware of crossover / driver anomalies that slowed the edges of notes, broke the synchronization of percussion with brass and slowed the output of ranges from treble on down.  The music was all there, shading and dynamics etc etc, but the recordings lost that lockstep timing or unison, a Slight blurring of instrumental notes that is normally undetected.  Speakers have been the bigger culprit in the change or lack of PRaT for me.  Electronics and cabling can have some deleterious effects but driver and crossover implementation tend to wave a bigger flag for me when it comes to decreasing PRaT.   For me full range speakers that marry woofer, mids and tweeters in phase and speed offer that sense of unity or unison

@audition__audio 1+

@dogearedaudio There are several aspects to stereo imaging that help define a systems performance. Imaging specificity is essentially the "focus" of the image. With the best systems and recordings each instrument and voice is sharply defined in 3 dimensional space with "blackness" (no sound) in between. In most systems the individual sound sources blend into each other. With a large number of instruments, like a symphony orchestra there is a solid wall of sound. Instruments still occupy a location, but they blend into each other whether one likes it or not.  Imaging the third dimension is not where in instrument is located in 3 dimensional space it is the sensation that an instrument or voice is not a flat object on a painting but a three dimensional object in space. This is the sensation that the singer is in the room with you. This is the hardest aspect of stereo performance to achieve. Very few systems will do this and only with a limited number of recordings. A 3D soundstage is imaging in 3 dimensional space. Some instruments are up front and others behind. In many instances this is artificial. The recording engineer is doing this with echo. It is best to evaluate this with a live recording as fewer tricks are used in their production. A good recording of a symphony orchestra should easily demonstrate that the tympany is at the back of the stage. 

Sometimes audiophiles will refer to a soundstage as being wide and will relate that their system images out beyond their speakers. You can throw an image beyond the speakers with phasing tricks, but in the absence of these the system soundstage should be defined by the distance between the speakers and the listener's distance from the speakers. Imaging beyond the speakers is due to reflections off the side walls and always represents a problem that diminishes image specificity. For a system to have the best image specificity the frequency response curve of the two channels has to be identical. This is very difficult to achieve usually due to room issues. This is not to say the frequency response of a system should be flat. To the contrary systems tuned to be flat sound bright and bass less.    

@rwortman

. . . The PRaT that audio writers prattle about is an illusion . . .

. . . and yet for some us, at least, the presentation of pace, rhythm and timing is discernibly different from one system to another.

@calvinandhobbes 

Orchestral music, as a vast generalization, tends to have interactions between the different instrumental sections that is of a nature that is not as quick and transient as those in jazz music.

Thanks for kindly pointing out what is probably obvious to many, here. I tend to favor smaller groups, which means I rarely listen to Big Band Jazz and never listen to orchestral music. My comments reflected my unfamiliarity/ignorance.

@stuartk I would agree that all musical genres benefit to some level from better PRaT, but my perspective is that whether PRaT is a key element to understanding the music will vary by genre. Some musical genres like jazz have frequent quick interactions between different musicians. Better PRaT makes it easier in my experience to follow what's going on in the music. Orchestral music, as a vast generalization, tends to have interactions between the different instrumental sections that is of a nature that is not as quick and transient as those in jazz music.

Music reproduction systems produce sound waves that can be characterized by their amplitude, phase, and any added distortions.  Pace, rhythm and timing is something music has.  Unless you are using a turntable running at the wrong speed nothing in your system is going to change pace, rhythm, or timing.  The PRaT that audio writers prattle about is an illusion caused by dips and bumps in the frequency response of speakers or turntables.  Everything else has ruler flat frequency and phase response.  More or less PRaT in a solid state amplifier or DAC is purely imaginary.

@yoyoyaya "... The irony is that the ... LP12 of the mid eighties had dreadful micro timing stability due to the movement of the subchassis/armboard relative to the platter. Linn’s mantra was pitch and rhythm."

I lived in the UK before Linn, when speakers were regarded as the dominant factor in audio quality. Ivor’s argument was that distortions introduced at the start of the audio reproduction chain were also important.

His starting point was that any sloppiness between the cartridge and the record would be amplified by the cartridge. His engineering solution was to couple the cartridge to the platter as tightly as possible in the direction of the arm tube. The bearings that allowed the arm to track the groove, and the platter to rotate, had to have minimum play.

If different materials were used, which expanded at different rates, changes in temperature would open up gaps. So every mechanical connecting component was made of the same grade of stainless steel. The soft floating suspension allowed the entire platter, sub-chassis, arm, cartridge system to move as one, keeping the relationship between the cartridge and the record consistent.

The most obvious difference from competitive players was the response to transients, especially scratches in the record itself. Others exhibited lengthy mechanical ringing whereas scratches were much less obtrusive with Linn. Ivor the showman illustrated this through his casual handling of records in demonstrations, often throwing them around. Elsewhere I have tried to emphasize the importance of transients for our perception of PRaT.

My recollection is that specifications were notably absent from discussions of Naim products!  The same went for the specifications of Rolls Royce car engines, where the output was described as "sufficient".

PR&T is simply an essential component in well reproduced music. We all strive for well reproduced music.  I often say ‘wow, listen to that tune, listen to that PR&T’. I also say ‘wow, that’s great music’.

Unfortunately it’s not a given that people understand or are receptive to “prat”
And that is not a criticism, hence why many folk are quite happy with Alexa music , car stereo music Blutooth speakers etc .
Naim equipment does it very well.

@richardbrand

Of course, the actual music does not really slow down, nor change in pitch, nor timing (unless stylus drag actually slows a turntable down!)..

But our perception of when the beat starts is affected by the arrival pattern in time of the first transients of a note. If the leading edge is sharp, not smeared in time, your brain will snap into recognising the start of something special. I am suggesting microseconds here! Get this right, and you’ll likely find your foot tapping ...

Seems plausible.

@calvinandhobbes

The type of music you’re listening to matters in term of whether PRaT is relevant.

 

Perhaps I simply don’t understand how you are defining PRaT or perhaps it’s the fact that how rhythms are presented by a system is vital to my engagement as a listener, but either way, I’m having difficulty grasping how any genre wouldn’t benefit from a system that presents PRaT well. . . unless one is solely listening to ambient music that "hovers" in space. 

My perception at the time when the phrase first appeared was that it was an anti spec approach to SQ evaluation.

Back then perceived quality of all audio components was based on spec analysis. 

@gregm Ivor Tiefenbrun was a brilliant marketer for sure. He took the essence of British Hi-Fi and translated that into words to get awareness in the US market. I think Linn's products back in the 70s and 80s were not so different from other audio components from the UK, but the main difference was that Ivor created a "philosophy" to describe what that British Hi-Fi sound did well.

He got what many engineers miss about marketing. It's about trying to sell your strengths, not covering up all weaknesses.

Bias a tube amp a little low in mA and you’ll hear sluggishness that is moving toward lower prat. 
 

while I like OP’s binary approach to how a system sounds (does it right or not), I think if you go back and relisten to what’s working and what’s not, you’ll find sometimes a system has great soundstage, imaging, etc But it’s still falling into the not doing it for you bucket. That might be a lack of prat. 
 

some folks just here things differently—like OP’s view on Klipsch.  To me, they can be good rock speakers but some Klipsch offerings can convey delicate pieces and dynamics in a way that makes others sound brutish. Yet, OP hears “in your face”.

one may never hear things and that’s a blessing or maybe a curse.   Not sure.  

Good summary Gregm. The irony is that the the LP12 of the mid eighties had dreadful micro timing stability due to the movement of the subchassis/armboard relative to the platter. Linn's mantra was pitch and rhythm. I have a feeing it was the journalists at The Flat Response magazine that converted that into PRaT.

While I understand where our friend, above, "actor, singer, stage director and audiobook narrator" is coming from, the acronym’s origins are different.

They were brilliantly marketed (perhaps coined, I don’t know) many decades ago by the owner of Linn to promote the sound of the Linn / Ittok TT + Naim amplification combo. The idea was to point to what those devices did well, excluding everything else (where they were mediocre).

The sound was somewhat mid-bass heavy, with mediocre resolution by today’s standards, but with very coherent mid-range restitution.
The overall sonic result was pleasant (my opinion - I used to have that combo).

@immatthewj ....20' above it, 50 yards from the mudfield....slept through the night mostly, waking to heavy rain and the winds.  Nil damage.

We're on the 'wrong side of the tracks' from the Biltmore entry, west of the McDowell bridge.  Everything betwixt was a sheet of clay-colored mud water...a leaning high-tension power tower (since replaced), the entry mentioned shattered...

Power back in 2.5 weeks, water back a week later....it's nice not to have to flush with a 5 g. bucket anymore....(...surprises one how often you end up doing that...).

Feel extremely lucky, and somewhat shell-shocked in some ways...

Your city got torn into halves.  Literally.

Too many stories to tell here...

Thanks for asking. ;) J

FWIW, electrostatic speakers have PRaT in spades because of extremely lightweight of their moving elements. 

My short definition for PRaT: You can clearly hear how different voices and instruments are interacting together in music. This is particularly evident in jazz music as a vast generality.

The type of music you're listening to matters in term of whether PRaT is relevant. I've listened to turntables that sound soft and somewhat indistinct rhythmically (typically high mass turntables), but their reproduction of the weight of orchestral music was stunningly good. For that music, I think pace and rhythm didn't matter much. On the other hand, jazz typically seems to benefit from equipment with some ability to reproduce pace and timing.

@yoyoyaya The Naim version of PRaT is easy to understand because it is focused on emphasizing the leading edge of notes while being harmonically lean. I've since found that the next level to PRaT involves music reproduction that has pace but is also harmonically full. Pass amplifiers fit that bill. I think @ghdprentice also mentioned that Audio Research is even better than Pass amplifiers at conveying both pace and tonal richness.

Of course, the actual music does not really slow down, nor change in pitch, nor timing (unless stylus drag actually slows a turntable down!)..

But our perception of when the beat starts is affected by the arrival pattern in time of the first transients of a note.  If the leading edge is sharp, not smeared in time, your brain will snap into recognising the start of something special.  I am suggesting microseconds here!  Get this right, and you'll likely find your foot tapping ... 

... what smears out transients in time is poor driver alignment, cancellation between drivers around cross-over points, and interfering reflections from room surfaces.  These are all reduced if your speakers behave like point sources.

OP,

Just because you don’t get it now, does not mean you will not over time. It took me decades. Then suddenly the lightbulb popped on.

I was in Dallas about twenty years ago. I went to this dealer / home… hobby gone wild. The entire house was completely crammed with high end gear. In the downstairs listening room he had a set of Sound Lab Millennium-1 Electrostatic Loudspeakers. They were powered by a Viva tube amp… 4wpc (?). He said, I know this is ridiculous… but listen to this. It was all midrange and some flabby bass. It brought tears to my eyes… immediately, I have never heard anything so beautiful, emotionally evocative in my life. I was completely shaken and emotionally drained when I left. I really didn’t know what to make of it.

I couldn’t consider buying into that system… nor was he trying necessarily to sell that sound… he was overwhelmed, as was I by the emotional connection. There was no detail… no treble… the bass was absurd. I tucked the experience into my memory.

It wasn’t for another ten years when I had this epiphany that my main system had become sterile and lifeless (a true “Reference” system) that it all came together. Different experiences with certain systems that had varying degrees of PRaT… I got it! One of those lightning bolt experiences. After that, I could detect it nearly instantly and its degree. For me it was the most difficult parameter to “get”, now one of the absolutely most important.

Keep at it. Starting this thread shows your curiosity. There is a long Stereophile article in the 90’s, lots of technical descriptions… did not do a bit of good for me. But trying to sense what that thing is that is making you want to tap your foot is the thing you want to pursue. Not by narrowly focusing, but by the gestalt of the sound.

Good luck.

@mkorsunsky

Ever heard of irony or phrasemes (fixed expressions)?​ ​​​

Yes. But when utilized without providing a context, they don’t communicate much.

While I appreciate the additional information, it’s still not clear to me how those two companies relate to a discussion of PRaT.

@soix If its fast, it must not be bright. If its detailed, again that should not be in tandem with brightness. IOW you're making progress when its both smooth and detailed at the same time.

The goal of the system is the music, such that you don't concern yourself about the sound of the system.

@atmasphere  Hey Ralph thanks so much for at least trying to explain what the hell I’m missing.  I get that a system needs to be fast enough to reproduce music effectively, but I just don’t get it.  It’s not a “thing” for me I guess.  Tone.  Imaging.  Soundstage. Yeah, I get all that.  But pace, rhythm, and timing?  No.  I’ll hear plodding bass if it’s overdone and slow, but that’s just not what I hear with most systems.  This “toe tapping” thing is just totally lost on me, and I guess I’m just missing it or don’t hear that way.  Linn and Naim can do their “thing” but I’ll never, ever own Linn speakers because they sound like nasally ass to me.  But that’s just me.  

the founder of Linn discussing the philosophic origins of his LP12 turntable

Was it the Thorens TD-150 that Linn knocked off? 😂😂

@soix To understand PRat, you have to understand that the ear/brain system has tipping points. If the system is too distorted, if its too slow, stuff like that, the music processing (which normally occurs in the limbic portion of the brain) is transferred to the cerebral cortex.

So the system has to be fast enough, smooth enough, detailed enough such that the music is processed in the limbic system. That way you get a more emotional reaction- more toe tapping and so on.

So a variety of things are going on, which is why there's no consensus above.

@stuartk 

Ever heard of irony or phrasemes (fixed expressions)?​ ​​​

Nothing criminal, of course. However, I do remember, some 40 years ago, at Harvey's (long-defunct mid- to high-end stereo shop in NYC) I, a customer, was trying to impress upon a salesman the importance of source-first approach to a stereo system. He cut me off: "I don't want to hear this BS". That was the time when both Linn and Naim tried to spread their Gospel, and other Hi-Fi manufacturers, their competitors, often mocked them (many still do).

BTW, I have been a committed Linn/Naim man ever since.

“Brits and Aussies would say that anyone who doesn't get PRaT must be a prat!”

:)

@asvjerry  , were you in the flood zone?

Brits and Aussies would say that anyone who doesn't get PRaT must be a prat!

Pitch, Rhythm and Time

@mkorsunsky

Why "partners in crime" ?

What is "criminal" about PRaT and how can any definition of music exclude harmony?

"Didn't someone say music is comprised of 2 things, rhythm and melody?"

Yes, that was Ivor Tiefenbrun, the founder of Linn, discussing the philosophic origins of his LP12 turntable in an interview many years ago. The term PRaT, I believe, originate with some people at Naim, Linn's partners in crime at the time.

The tube amps that sit next to the Audion based system always sound most Prat-ey after a few hours of warm-up in the early evening before a midnightish listening session. Time of day is a factor or rather the state of the "grid" which tends to be more Prat sounding after midnight. Also, the tube amps (pre and power) transformers have warmed up enough to be "saturated." State of the grid and transformer saturation have a big bearing on PRAT in this household and moreso with the tube amps than the GanFet amps.

@nonoise Yes that helps. Even though can’t hear them I will research. They must have a really good x-over. BTW, I have that same tuner circa 2001. Bought before Marantz did their major downgrade.

@soix 

"Really?  Seriously???  Why are you even here if you don’t get these simple concepts?"

You already asked me that and I answered you.

....the Kimmel version has some serious bass... 

...theme for the next 4+ years. Yes

PRaT...a newish ’buzz’ acronym to kick about ’n argue about.... ;)

I'm annoyed....deal...:(

@cdc , Sure, I've mentioned it before so it's not like it's some secret. 

My integrated is the Technics SU-G700M2 with the matching  SL-G700 SACD player. My speakers are the Revival Audio Atalante 3 monitors w/matching stands. My cabling consists of Darwin Audio speaker cables and interconnects and the power cords are a mix of TWL and Zu Audio with a Audioquest Niagara 1200 power and conditioner/surge protector. I also use IsoAcoustic Oreas under the integrated and SACD player and I have an old Marantz ST6000 tuner that is now quite satisfying to listen to thanks to the aforementioned. 

As usual, YMMV but for me, I'm quite content until I win the lottery and dig deeper for the bigger Atalante 5 speakers to use in a bigger, dedicated place. Hope that helps to point the way or at least give an idea of what can work.

All the best,
Nonoise

A please define for me what "imaging" and "3D soundstage" mean.  In relation to what?  And why are they important?

@dogearedaudio  Really?  Seriously???  Why are you even here if you don’t get these simple concepts?  

"this is one fast system".

@nonoise  care to share what it is?

Some get it,

Some don't,

All the best,
Nonoise

Pace is the speed, rhythm is the repetitive beat, timing is the emphasis. Music, stand-up comedy, the stage, film, writing--success in these crafts is largely defined by these three simple but discrete elements.

@dogearedaudio +1. Alec Guinness, Anthony Hopkins IMHO made you want to listen to them and convincing because of the way they used Prat to express their lines.

How do you listen to pace and rhythm? Forget about it.

@jayctoy You don’t listen to it like detail imaging etc. You feel it.

Didn't someone say music is comprised of 2 things, rhythm and melody?