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Pace, rhythm and timing. What do these terms mean to you with respect to hifi?

Mullardman said:
Forgive me if I conveyed the wrong impression in my quest for brevity. ;) I was of course referring to the existence or otherwise of PRaT in audio components.

Thus yours is of course the correct answer to the wrong question, especially when coming from a confirmed Linn acolyte, and even more especially considering that PRaT only appears to have emerged as a claimed issue in hi fi equipment in recent decades. Few would, I think claim that PRaT does not exist in music. Whether individuals can hear it is of course moot, but in my own experience some place more emphasis on what they think constitues PRaT than do others. Also, I know many people who do not seem to respond to any music which majors on melody, as opposed to some sort of propulsive beat or rhythm.. but I will posit that as an example of taste, rather than perception.

Quite evidently, pace, rhythm and timing are all part of the fabric of music. It follows that those elements should be reproduced as faithfully as is technically achieveable by the hi-fi system. However, the idea that some components 'have PRaT', whilst others don't, is IMHO, and as I said above.. bolleaux. All of those elements are reproduced electronically, within usually tin boxes full of bits. The speed of electrical transmission AIUI, is the same as that of light. I.E. 186000 miles per second. It is I believe true that audio signal transmission 'speed' through wires varies somewhat according to frequency. This will in theory produce some 'smearing' of the signal, but only, AIUI, over considerable cable lengths. It also appears to be a function of physical laws relating to signal transmission:frequency, so, apart from using the best available wires/dielectrics etc.. even the best audio designers are powerless against this physical certainty.

Which brings me to my long held conclusion that what is marketed as, or masquerades as 'PRaT', in audio components, is simply a designed in frequency response which creates leading edge emphasis, maybe a bit of selective HF boost, and an emphasis on upper bass... which can be perceived to represent PRaT, but which is nothing of the sort.
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That meandering waffle only serves to undermine your position, you get that, right?
 
My main experience with PRaT was when I went to a well-known shop in London to demo the 700 amps. They started off using the bariks of the period. Feet were tapped, but I thought the sound was lousy. Overblown and muddled. Quite different to all the other speakers I'd used with the amps - in a bad way. No stereo image. No real clarity. Also the two speakers clearly weren't a pair. They *looked* the same, but sounded different to each other.

I commented on this and the shop-droids tried to dismiss what I said. (And the sales-director from Armstrong tried to hush me up because he worried I'd piss them off. But I persisted, politely.) The shop-drioids insisted that stereo image was a bit of a myth, anyway.

After a while they agreed to investigate. We found that one of the bariks had a 'popped' tweeter that was clearly damaged. They tried to fix this, but gave up as it was damaged. Either they'd never noticed, or knew but didn't care.

They brought out - reluctantly - a pair of ESL63s which were new at the time. We tried them. Stunningly better sound, and a real stereo image. This was actually my first chance to hear a pair of '63s. The droids made clear that they didn't think much of the ESLs, but had them just in case someone insisted.

The experience was a revelation in more ways than one. And I was left feeling that, in terms of honesty, I'd been a PRaT if I'd shut up and gone along with the confident drivel the sales-droids were spouting. However I probably was one for risking losing sales. But TBH I doubt they'd have bought from us anyway until there might have been a 'bandwaggon' to jump on.

So, no, even in one of the dem-rooms that sold many bariks, etc, I didn't hear any PRaT of the kind talked about in magazine reviews. Interesting experience, though, and led me to buy and use a successions of ESLs.
 
Exactly what I heard the first time I listened to a top Naim/Linn system. Never again.
I happened to also be able listen to a full Quad system at the same time (1981) at a different dealer’s.
And yes, what a revelation it was!
 
Jim Audiomisc said:
My main experience with PRaT was when I went to a well-known shop in London to demo the 700 amps. They started off using the bariks of the period. Feet were tapped, but I thought the sound was lousy. Overblown and muddled. Quite different to all the other speakers I'd used with the amps - in a bad way. No stereo image. No real clarity. Also the two speakers clearly weren't a pair. They *looked* the same, but sounded different to each other.

I commented on this and the shop-droids tried to dismiss what I said. (And the sales-director from Armstrong tried to hush me up because he worried I'd piss them off. But I persisted, politely.) The shop-drioids insisted that stereo image was a bit of a myth, anyway.

After a while they agreed to investigate. We found that one of the bariks had a 'popped' tweeter that was clearly damaged. They tried to fix this, but gave up as it was damaged. Either they'd never noticed, or knew but didn't care.

They brought out - reluctantly - a pair of ESL63s which were new at the time. We tried them. Stunningly better sound, and a real stereo image. This was actually my first chance to hear a pair of '63s. The droids made clear that they didn't think much of the ESLs, but had them just in case someone insisted.

The experience was a revelation in more ways than one. And I was left feeling that, in terms of honesty, I'd been a PRaT if I'd shut up and gone along with the confident drivel the sales-droids were spouting. However I probably was one for risking losing sales. But TBH I doubt they'd have bought from us anyway until there might have been a 'bandwaggon' to jump on.

So, no, even in one of the dem-rooms that sold many bariks, etc, I didn't hear any PRaT of the kind talked about in magazine reviews. Interesting experience, though, and led me to buy and use a successions of ESLs.
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I think that many us, in possession of an open mind, went through a similar experience back in the 1980s.
 
Mullardman said:
Which brings me to my long held conclusion that what is marketed as, or masquerades as 'PRaT', in audio components, is simply a designed in frequency response which creates leading edge emphasis, maybe a bit of selective HF boost, and an emphasis on upper bass... which can be perceived to represent PRaT, but which is nothing of the sort.
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Please provide an example of a piece of kit with this non-flat frequency response, and the measurements.
 
Well that's not easy to do from here, because most manufacturers only quote a frequency response in crude terms such as 'X Hz-X KHz -3db' ..and as we all know 3db represents a pretty big change in signal power. Down by half I think. Surely such a spec provides ample opportunity for the odd lift/dip here and there?

Also, I'm not an electronics engineer and don't claim to understand the finer points, so have to describe what I hear in largely layman's terms. I have heard kit which audibly majors on leading edges, without developing the full 'envelope' of any given note. To my ears, this produces a lively, 'bouncy' sound, which can be initially appealing, but which is hardly accurate. Add in the upper bass prominence etc.. and you have what I'm talking about. This sort of sound seems, in my experience both as a punter and a sometime audio salesman, to appeal to a certain type of music fan who.. to put it bluntly, wants all music turned into a 'punchy', propulsive and foot tapping experience. Their choice obvs, but it's not hi-fi to these ears... and it has no real relevance to the true PRaT which exists within the music rather than the kit.
 
Their choice obvs, but it's not hi-fi to these ears... and it has no real relevance to the true PRaT which exists within the music rather than the kit.
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Exactly. Within the music. As I said before, I can listen to and dance on music played from a Google Home if that’s the only source available.
Not hi-fi, but still. It’s the music that matters.
 
Mullardman said:
Well that's not easy to do from here, because most manufacturers only quote a frequency response in crude terms such as 'X Hz-X KHz -3db' ..and as we all know 3db represents a pretty big change in signal power. Down by half I think. Surely such a spec provides ample opportunity for the odd lift/dip here and there?

Also, I'm not an electronics engineer and don't claim to understand the finer points, so have to describe what I hear in largely layman's terms. I have heard kit which audibly majors on leading edges, without developing the full 'envelope' of any given note. To my ears, this produces a lively, 'bouncy' sound, which can be initially appealing, but which is hardly accurate. Add in the upper bass prominence etc.. and you have what I'm talking about. This sort of sound seems, in my experience both as a punter and a sometime audio salesman, to appeal to a certain type of music fan who.. to put it bluntly, wants all music turned into a 'punchy', propulsive and foot tapping experience. Their choice obvs, but it's not hi-fi to these ears... and it has no real relevance to the true PRaT which exists within the music rather than the kit.
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I agree with your viewpoint (on artificial PRaT), but I don't think it is apparent in any frequency response measurements I've ever seen or made.

Except...
There is one measurement I am aware of that strongly relates with BLaB (true PRaT) and that is the LF response of loudspeakers.
 
I can listen to music with no bass at all that is rhythmic.
The one who can define PR&T will get a PFM Nobel Prize :p
 
S-Man said:
Please provide an example of a piece of kit with this non-flat frequency response, and the measurements.
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The specific meaning of "this" is your statement might need to be defined. But when it comes to loudspeakers the *norm* is a response that isn't flat. Just as is the norm for them to have an impedance that isn't the same across the audio band.

Add in the way that can also depend on the impedance of the amp driving it, and you can get a range of responses such that someone may prefer a particular result from a specific pairing.

And the old bariks had an impedance vs frequency plot that was a far cry from a flat resistance, for example.

P.S. And a speaker can also have an impedance that varies with signal level and recent use history, and be asymmetric. 8-] I can recall watching bass cones trying to pull back into the box, or push their way out of it when loud music was played. Curious 'rectifier' effect.
 
Mullardman said:
Well that's not easy to do from here, because most manufacturers only quote a frequency response in crude terms such as 'X Hz-X KHz -3db' ..and as we all know 3db represents a pretty big change in signal power. Down by half I think. Surely such a spec provides ample opportunity for the odd lift/dip here and there?

Also, I'm not an electronics engineer and don't claim to understand the finer points, so have to describe what I hear in largely layman's terms. I have heard kit which audibly majors on leading edges, without developing the full 'envelope' of any given note.
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Add in the complication of the various distortion methods which speakers tend to exhibit. More complex than most amps and very dependent on signal pattern details. cf above.
 
I think your all starting to get close..
Back emf is one the main sound killers
It varies with speaker type, music and amplifier type.
 
Jim Audiomisc said:
Add in the complication of the various distortion methods which speakers tend to exhibit. More complex than most amps and very dependent on signal pattern details. cf above.
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Indeed. My own long term speakers are Rogers Studio 3. They have a fairly high overall impedance which I believe stays mostly above 6 ohms, so that while pretty insensitive, they are not a 'difficult' load. They exhibit many of the properties of the LS3-5A, but with a bit more bass. With the addition of the AB3 auxiliary bass units, they produce a bit more bass still and of course the impedance/frequency response will be different. All I know is that they are driven well by my LFD Zero. They are never going to produce 'seismic' bass, but they do clarity, tonal accuracy, imaging and soundstaging very well. I'm happy with that.
 
Jim Audiomisc said:
The specific meaning of "this" is your statement might need to be defined. But when it comes to loudspeakers the *norm* is a response that isn't flat. Just as is the norm for them to have an impedance that isn't the same across the audio band.

Add in the way that can also depend on the impedance of the amp driving it, and you can get a range of responses such that someone may prefer a particular result from a specific pairing.

And the old bariks had an impedance vs frequency plot that was a far cry from a flat resistance, for example.

P.S. And a speaker can also have an impedance that varies with signal level and recent use history, and be asymmetric. 8-] I can recall watching bass cones trying to pull back into the box, or push their way out of it when loud music was played. Curious 'rectifier' effect.
Click to expand...


The DMS measurements do contain clues that indicate why it has decent time domain performance at LF:
http://www.mickandviv.com/pfm/DMSHiFiforPleasureReview.pdf

... the slope of the LF rolloff is approx 12dB/oct i.e. 2nd order
 
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