Define it for me... Slam, Ring & Dynamics

One that always has me scratching my head is PRAT (Pace, Rhythm and Timing) when referring to turntable performance. Seems to often be used when someone is describing the benefits of idler driven units. I would think if a table is working in spec and turning at the precise speed it needs to, I'm not sure what good "PRAT" is in regards to a table's quality?
 
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One that always has me scratching my head is PRAT (Pace, Rhythm and Timing) when referring to turntable performance. Seems to often be used when someone is describing the benefits of idler driven units. I would think if a table is working in spec and turning at the precise speed it needs to, what good "PRAT" is in regards to a table's quality?

It's just as meaningless as fast bass. You'll find similar utterances bandied about by wine connoisseurs. They are attempting to find words to describe their subjective experience and created a jargon to do so.

IMHO: Ring is always negative; Slam is an overemphasis in the 50-80Hz range; and Dynamics is the relative rise time between loud and soft changes in the music coupled with how well a given transducer can follow those changes.
 
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Well I talked to Blue Shadow on the phone and I now agree with his notions on dynamics, as well as my own. I don't think they conflict but are both part of what makes for good dynamics. My wife was in on the conversation as well and she helped set me straight. She helped by describing how she experienced dynamics with our Martin Logans--not just as getting louder but getting bigger and more emotional because of the excellent portrayal of dynamic subtleties.

In any event it's clear my emphasis on dynamic range as describing good dynamics was simplistic.
 
I would differ re fast bass. A woofer that can nail a kick drum and then stop dead has fast bass. A 15" woofer that only moves 1" with great accuracy and minimal distortion is going to sound better than a 10" woofer that has to have an excursion of 3", with 5% distortion, and a huge overhang after the event.

There are engineering paradigms that frame and help define all these terms - they are not merely made up words.
 
IMHO: Ring is always negative; Slam is an overemphasis in the 50-80Hz range; and Dynamics is the relative rise time between loud and soft changes in the music coupled with how well a given transducer can follow those changes.

Well this is a good discussion we're having. I guess I'd like to ask if music is all "audible" or if there is perhaps a physical extension to it beyond what we hear? I know Bass can set up resonances in us physically. So is this sense of the physical dimension of Bass maybe associated with the sense of Slam? Is it really an "overemphasis" or is it actually an accurate reflection of that physical element?
 
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I would differ re fast bass. A woofer that can nail a kick drum and then stop dead has fast bass. A 15" woofer that only moves 1" with great accuracy and minimal distortion is going to sound better than a 10" woofer that has to have an excursion of 3", with 5% distortion, and a huge overhang after the event.

There are engineering paradigms that frame and help define all these terms - they are not merely made up words.

So fast bass merely means accurate bass. IMHO, bass is either accurate or not, but the term "fast bass" doesn't add anything, and likely, gives some people the notion that lower frequencies propagate faster. IIRC, Ken Kantor discussed this here a few years back. Wave propagation speed is independent of frequency; thus, high and low frequencies propagate at the same rate.
 
Propagation speed is also influenced by the strength of the driver magnetic field, the level of travel control, the rate of recovery, the level of speaker deformation, and a multitude of cone and driver behaviours.

Keep in mind that these behaviours don't occur in unitary fashion, but many, many times over a period of a minute during a song. The woofer cones we deal with have a feedback mechanism internal to the cone, they have a feedback mechanism with the surround, they have a feedback mechanism with the voice coil and magnet assembly, they have a feedback mechanism with the speaker enclosure, and a feedback mechanism with the amplifier. A woofer that is not designed to account for all these interactions is going to reveal shortcomings along the path, ones that allow it to work within design parameters with ease, or fail at multiple facets.

Fast bass allows the woofer to recover and reproduce the next impulse event in the shortest period, or number of cycles, possible. Conversely, a woofer that is not rigorously designed can still be dealing with the first propogation event five beats later. This is the basis for fast bass vs bloated bass.
 
A well damped woofer system (system meaning the driver and the enclosure tuning) can give the effect called fast bass. Unless that well damped woofer is also burdened by large amounts of distortion in which case a less well damped but lower distortion system can sound "faster". It all depends.
 
She helped by describing how she experienced dynamics with our Martin Logans--not just as getting louder but getting bigger and more emotional because of the excellent portrayal of dynamic subtleties.

I'm with her, and feel when I talk about the dynamics it's how the system as a whole handles the transient peaks in musical recording. You can have a great speaker and not power them right to cover this as well as vice a versa, this will not be dynamic regardless of the quality of the source material.

Having very good speakers with plenty of clean power and a recording with wide transient peaks, is dynamics. Nothing is clipped, plenty of recovery power and speakers that have the speed without distortion.
 
Propagation speed is also influenced by the strength of the driver magnetic field, the level of travel control, the rate of recovery, the level of speaker deformation, and a multitude of cone and driver behaviors.
I agree with this, with a amp that can deliver a matched recovery speed that is unclipped.

Fast bass allows the woofer to recover and reproduce the next impulse event in the shortest period, or number of cycles, possible. Conversely, a woofer that is not rigorously designed can still be dealing with the first propagation event five beats later. This is the basis for fast bass vs bloated bass.

I agree with this, with a amp that can deliver a matched recovery speed that is unclipped.
 
A well damped woofer system (system meaning the driver and the enclosure tuning) can give the effect called fast bass. Unless that well damped woofer is also burdened by large amounts of distortion in which case a less well damped but lower distortion system can sound "faster". It all depends.

I like this Tom! I think what I have been touching on can best be described as "Resonance". Obviously you want to control the resonance of a room, but the resonance of a speaker can be by design an can provide a level of physio-acoustic dimension that is tough to quantify. It makes me wonder how folks like Sir Raymond Cook, John Wright and John Dunlavy (the devotes of acoustic measurement) factored in these elements?

I mean think about all of the work done on the Thin-walled BBC Enclosures and Transmission Lines... with the tools they had at the time they could get a sense of how a cabinet responded, but what were they trying to achieve? Was it truely to balance dampening of the drivers, or was there something more they were going after?

Makes me wonder what they would add to this discussion coming from the great minds of not just engineers, but craftsmen!
 
One that always has me scratching my head is PRAT (Pace, Rhythm and Timing)...

Good stuff Sand-man... I think of PRAT in a speaker as the Dynamic Response we've been discussing. Not sure how that relates to a Turntable, but perhaps the Cartridge pre-amp...

As for Dynamic Response of a speaker and how that relates to the Resonance (Ring/Slam), maybe we're getting close to another topic associated with "Accuracy", "Linearity" and "Coloration"!

Oh this is fun!
 
No.

just be cause one can play it loud with lots of watts or play it quiet with few watts, that is the dynamic range. But when one plays it at a moderate or high volume and the difference between the low volume and high volume at the one playback level, the greater the difference, the greater the dynamics of the speaker.

How often do you read that speaker A really opens up with a big amp? That speaker might not have the greatest dynamics compared to one that doesn't require a big amp to get going. Not that this is an indication of quality of the speakers, just differences.
YOU have nailed it.:beerchug:

I feel this thread as a good ring to it.
 
Well I talked to Blue Shadow on the phone and I now agree with his notions on dynamics, as well as my own. I don't think they conflict but are both part of what makes for good dynamics. My wife was in on the conversation as well and she helped set me straight. She helped by describing how she experienced dynamics with our Martin Logans--not just as getting louder but getting bigger and more emotional because of the excellent portrayal of dynamic subtleties.

In any event it's clear my emphasis on dynamic range as describing good dynamics was simplistic.

reread you post and you discussed the lack of dynamics due to overdriving the system whether that be the amp not putting out or the speaker just not moving any further with more input level and this is a lack of dynamics. I addressed the concept as it applies overall to different speakers instead of just one.

As far as including your wife in the discussion, as soon as her opinion is known, that is the one you need to agree with.
 
I'm going to start some threads on Terms we seem to use around here on AK and lets just call it "Define it for me". I'll try to cluster these under a grouping that seems logical. I'll try to make it fun and maybe we'll all learn something and come up with new terms!

So let's start with what many may think are the same thing, but which might not be. When someone says a speaker has a "Ring" to them, what might they mean? Is the ring of a speaker related to "Slam" or is Slam really all about the Bass drive of a speaker. And how do Ring and Slam relate to the "Dynamics" of a speaker?

Thoughts oh wise AK'ers???
Here's some wisdom: the last thing we need is 'new terms'. What we do need is consensus on what the terms we already have, mean.
Would it be fair to say a speaker with great 'slam' is great 'dynamically'? My experience is with B&W 801, Kef 105, and Infinity Kappa 9. These are all competitive in terms of the op. They do it well. But the contrast from very low level to thunder is easily best defined by my Acoustat Monitor 3. No comparison whatsoever. Totally effortless and open. It's like a serious dynamic range expander was inserted. They produce spls of 120db 20 feet away on axis. Call it what you will, but I call it transparency. However, imo 'slam' is appropriately attributable to amplifiers, 'dynamics' to speakers. Directly driven ESLs have it all. If they don't, you have the wrong ESLs.:)
 
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