What does 'Fast mean?

This might sound ignorant but can someone describe to me what is meant when cables or equipment for that matter is said to be 'fast'?
I have always interpreted it to mean that the attack on leading edges and transients is well defined, and there is an apparent lack of overhang or ringing after the note. It makes music exciting, but too much of it can be fatiguing.
I think Seantaylor99 has it right. The Transient response makes music "jump" rather than just kind of drag along because of the fast attach and decay.
Seandtaylor99, I agree with everything but the last clause of your final sentence. Accurate reproduction as you describe it does not, in and of itself, render sound fatiguing. What it does do is expose sonic artifacts that would be "rounded off" by slower gear. If an entire system is fast and accurate, this usually exposes the sonic shortcomings of the recording engineering, which is where a lot of the nasties start out. Whether it is worth paying the price of reducing overall transparency to mask some of these irritants is a question worth debating.
What reading glasses can do to make things clear.As we get old we get "used" to the way things are.Reading glasses clear things up again "quickly"...giving us that wow!!!. Getting used to a sound "your sound" then all of the sudden there is a change ,....because change was made.If it was a good change,for the better ,it probably cleared things up a bit....WOW.So it sounds fast again.
Glider, the reason for my final sentence is because I believe some audio gear overemphasises attack to make demos more exciting and sell more. More accurate does not necessarily mean more attack.

There is also definitely some gear that lessens attack and softens everything .... some will prefer this presentation.
I've always thought of "fast" as referring to the back end of the waveform. It doesn't have any overhang or ringing. The initial transient is handled pretty well by most components, but only a few components can stop as quickly as they start. In electronics it's probably a factor of the power supply and with speakers the crossover and mass of the driver. If a component distorts the leading transient signal it can make for a faster overall presentation, but will lead to long term fatigue.

Language is always a little misleading when describing what we hear.
In the tube world fast would be Telefunken 806S, 803s, GEC CV4085
Do you mean that it's faster than the speed of sound? My light bulbs can do speed of light you know.

I don't want to attack anybody...Just showing you an example ...cool.

Hi -fi ,still obeys natural laws...Yet audiophiles LOL
Fast is nonsense. Any properly designed cable or equipment has more than enuf speed to reproduce music & other recorded sounds. Same applies to PRAT.
Chopping off the overhang can be unnatural reproduction of music. A balance is needed for accuracy - the world is not all black and white. Arthur
Seandtaylor99, I don't want to come across as an objectivist here, because I'm anything but. However, if audio gear overemphasizes attack, I wouldn't call that "fast" , I'd call that distortion. Truly fast gear will track complex waveforms precisely, neither lagging behind rising edges or overshooting trailing edges. Anything else is distortion, and while it might sound exciting, as you note it wears thin pretty fast.

So, while I agree with you about those edges (it's like oversharpening in Photoshop for those familiar with digital photo editing) it's not fast in the sense that I think our original poster was inquiring about. That kind of fast you just shouldn't notice once you've gotten over the initial "Holy cow that's good!" reaction. After that, it's just the recorded signal.
Isn't that why some amps weigh a great deal, it slows them down, not very fast at all. Or you hear a track on your favorite CD, it is so fast, your not sure you heard it. Personally I think the speed of an amp is dictated by the ability of the amps power supply to recover or recharge itself after louder transients. I'm I right?
Porziob ... it's pretty easy to design a speaker cable with enough inductance to roll off higher frequencies. Too much capacitance and a wide bandwidth amp might start to oscillate.

Similarly it's pretty easy to design an interconnect with enough capacitance (usually the shielding) to cause rolloff where the source has a marginally high output impedance and the amplifier a marginally low input impedance. Not enough shielding and RFI becomes a problem.

The ability of an amplifier to control the speaker to deliver dynamic transients with little ringing or overhang is certainly not something all amps share ... hence the difference in sound.

It's not quite so simple as you imply.
my girl friend says im fast maybe i need to learn how to oscillate..funny about thats why amps are heavey phd
You can listen to more music in less time.
I take "fast" to mean how quick the output of a device can follow a change at the input - which would pretty much describe the above impressions of transients, attack, etc. As for cables, well... they either do the job or they don't. Poorly designed cables will result in modifiers such as "bright" or "bloated" while the good ones are hardly distinguishable unless you really move up the food chain in equipment. All this IMHO, as I have not heard all or every possible combination of gear.
Slew rate/damping factor
fast means no smearing of the sound.
Fast usually means the sound is thin and without body/weight making it seem faster! That is what I have found when auditioning "fast" gear.

Like my amp, my typing skills are fast but unlike my amp, I am not accurate. Rwwear, I agree more is better than less. Bbaxely2, it is understandable your girlfriend would prefer a slower hand, good sense of humor!

In all seriousness an amp with several small caps can recharge themselves more quickly than say only two or four much larger caps. Like the McCormack amps using several small caps with each one located close to each individual output device equals a fast amp. This can be heard but difficult to descibe. Cannot speak for cabling and its contribution to this phenominum, I never changed cable to prove this theory only to improve & get the desired sound quality.
Glidewriter, is right when he says, "Truly fast gear will track complex waveforms precisely, neither lagging behind rising edges or overshooting trailing edges."

As an example, Class D amps are fast. They don't waste nearly as much energy during their switching chores, so can more adroitly cover complex passages. If you have a fast transducer, you are in for a treat.
Oh, other classes of well designed amps can`t track the input signal as acurately or quickly? NONSENSE.
Two points to answer:

"Fast is nonsense.... Same applies to PRAT."

No, Porziob, this statement is nonsense, at least to me. It is beyond me why people who have never experienced systems that do PRAT well insist that it doesn't exist. It most certainly does exist. Whether these systems are your preference is another matter entirely.

"Fast usually means the sound is thin and without body/weight making it seem faster! That is what I have found when auditioning "fast" gear."

Now I do not think this statement is nonsense, Grannyring. While I wouldn't put the matter in such pejorative terms, I think there is truth here. As far as I can tell the subjective experience elicited by systems that we say are fast or do PRAT well does seem to come at a cost of reducing the fullness of the sound, creating at least some degree of leanness in the music. What one gets in return is a musical tightness - a rhythmic coherence - that many of us find captivating and involving. Too much of this leanness can be as dissatisfying to some ears as bloated tube gear is to mine. (I don’t find all tube gear unpleasant - just the soft, mushy-mouthed stuff.) We all have our preferences.
Agree with Proziob.
Fast means nothing in electronics 'cause you should neglect the speed of a sound to a speed of an electron.

In speakers it's a proper mechanical response of a driver. The fastest speakers in this issue are heaphones period.
Again, my 1970's hand held, transistor radio sounded fast. Why? Because it produced threadbare sounding music without body, soul and foundation. It played a 3 minute song in 3 minutes just like a Lamm SET amp - no faster.

A Mcintosh 402 amp won't sound fast, but rather it will sound beautiful and full. A Toshiba 3950 DVD player (I own one and like it for the money - $49 after rebate) sounds very fast due to its lack of body and weight. Perhaps I am to simple here, but it sure seems that way to my ears.
Michael Johnson in the 200. THAT's fast!
Boa2, that does sound fast. You got anything faster? In regards to this hobby I do, how about a vacuum cleaner set to maximum suction hooked up to your wallet. Now that is fast! If you hear a sucking sound, you know where I've been. If anybody finds a wallet with my initials, please at least return the credit cards & drivers license, you keep the wallet & what little money if any, remains.
They're hyperfast
Al DiMeola, John McLaughlin, Paco DeLucia...
Ingwie Malmsteen, Jeff Beck, FZ...
Michael Brecker(huh whish him to get better), John Zorn, Evan Parker, Igor Butman...
Jasper Van't Hoff, Chick Corea, Sergei Kuriokhin, Sasi Shalom, Pablo Ziglier...
Jeff Berlin, Percy Jones, Tony Levin
Mike Portnoi, Bill Brufford, Larse Ulrich, Mark Nauseef, Nana Vasconcielos, Trilok Gurtu, Zakhir Hussain...
Stupendous amount of interesting (and some not so interesting) posts, few of which addressed the original question: simply, when one says "fast" what does one mean (speaking of reproduced sound).
Generally, it's what Seandtaylor wrote. Whether it's due to power supplies, correct hi-frequency reproduction, no ringing, no significant phase anomalies... is another matter.
Or, at least, Hayds forgot to ask.
BTW, "pratt" (lovely stuff from Linn's marketing) can be achieved in systems by slightly emphasising the lower mid-range/upper bass.
"BTW, "pratt" (lovely stuff from Linn's marketing) can be achieved in systems by slightly emphasising the lower mid-range/upper bass"

I own Linn gear, though I have never heard the term "PRAT" from the mouth of any of the three Linn dealers I have worked with in the past two years. But I am too young in the hobby to know the marketing history behind these terms. I actually assumed the term was Naim's coinage.

I don't understand the distinction you are drawing between the terms "PRAT" and "fast." At least I have been using them interchangeably, perhaps in ignorance. Could you explain what you mean? Certainly increasing midbass doesn't lead to the phenomenon Seantaylor is describing above.

In my experience, such as it is, the excitement, immediacy and rhythmic coherence of music clearly varies from system to system (most dramatically between some tube gear and good solid state). I am sure midbass can give you the “thump - thump” of a dance club, but I doubt that is what you mean. It is certainly not what I mean when I use the term “PRAT.”
Newmanoc: Would you please enlighten us with a definition of each of the following terms in the context of the audiophile community:

Pace -
Rhythm -
Timing -

Thank you for your time.

John (jafox):
Of course they all mean the same thing. I have never met anyone who has been able to describe any meaningful differences between the constituents of this acronym, nor do I expect to. I use it simply because it is recognizable and seems to have found its way into the audio argot, not because I defend its origins, semantics or anything else. Perhaps I should just use "fast" or "well paced" in the future, because that is all I mean.

Newmanoc: actually I think you're right in that "pratt" probably originated with Naim when the two Cos were working closely together. THEN the Linn marketing/sales people did quite a lot of use of that with their dealers. It;s gone out of fashion now I suppose...

Loosely defined, the erstwhile "pratt" meant a "crispy" sound in the all important 100-10kHz region with close focus on 300-~6kHz: the point was to get FR and phase as good as possible in that range (think of the old LP12).

Much of the music listened to & used for auditioning at the time was rythmic (4/4, 8/4 etc) with vocals. Sooo, if you focused on the main part of the frequency spectrum rather than the extensions -- i.e. your 300Hz blended in well with the 5kHz say -- you had this lively, pleasant sound. I.e. "foot-tapping" sound as the good Mr Tiefenbrun used to say.
Focus on the range & its slight prominence also meant that with speakers reasonably (but not painstakingly) set up, the "springy" effect was still there.
Voila in reductionist and simplified form. Linn & Naim can offer a much more precise & sophisticated explanation, of course. Cheers
I think the point here is harmonic reproduction - not the speed of light or the switching speed of devices.

Reproducing harmonics means reproducing music. The question is whether the harmonics we hear are from the media or the electronics. The electronics can add harmonics (distortion) or remove them (low bandwidth and/or stability).

Problem is that there is no reference point - hence all the debates found in audio forums, including this one.

Thank you - your post was very informative and very helpful. Your description of systems designed for "PRaT" slightly emphasizing frequencies across the core of the audible frequency range makes sense to me. This is perhaps what people mean when they talk about "smearing" of sound from these systems (a term that strikes me as a little harsh). It does seem that systems that have this "crispy" sound do so at the cost of sacrificing things that others value more, such as the frequency extensions and low level detail (if I understand this latter term correctly). I suppose what to one man sounds like musical coherence to another sounds like sonic oversimplification. I think this "PRaTy" emphasis sounds less “audiophile” and more like live music. But my ears are not everyone’s ears, nor my tastes their tastes. Thanks again for your helpful post.