I have to agree, that unless 'fast' is carefully defined (and even if it is, there's enough history of use that such a definition will be largely ignored), it has no more meaning than the insidious audiophile acronym PRAT.
Ive asked a audio engineer whats his definition of a fast driver:
heres his response, hope it helps op
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Good "acceleration factor" (you won't find this in any text book, it is my attempt to explain something), this is basically the force factor divided by the moving mass (with air-load) and for convenient reading multiplied by 100. Drivers with higher value for this, independent from frequency response, tend to sound "faster" in the bass.
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heres his response, hope it helps op
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Good "acceleration factor" (you won't find this in any text book, it is my attempt to explain something), this is basically the force factor divided by the moving mass (with air-load) and for convenient reading multiplied by 100. Drivers with higher value for this, independent from frequency response, tend to sound "faster" in the bass.
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Steady-state test signals are only going to get you so far.
Something like Linkwitz's shaped tone burst is likely to be more interesting.
https://www.linkwitzlab.com/mid_dist.htm
Something like Linkwitz's shaped tone burst is likely to be more interesting.
https://www.linkwitzlab.com/mid_dist.htm
Existing one aspect of "fast" and "slow" not touched here. It is signal rise time.
Different speakers with nearly same frequency response can have different signal rise time. Mainly it can be caused by limited current from signal source or also DSP used to correct frequency response. Rise time can also be SPL level dependent.
Possibly it is not issue with AMT tweeters but can be with full range drivers.
Different speakers with nearly same frequency response can have different signal rise time. Mainly it can be caused by limited current from signal source or also DSP used to correct frequency response. Rise time can also be SPL level dependent.
Possibly it is not issue with AMT tweeters but can be with full range drivers.
I really didn't want to feel baited into this discussion, but I highly dislike these fancy, vaguely defining audiophile words and descriptions loosely thrown around by the high end audio industry. The agressive marketing strategies (online ads, social media, etc) coupled with the use of smart and hip sounding ignorant terminology is the mechanism used to lead its blind cult followers ignorantly like sheep to slaughter. People that throw around these smart, hip sounding audiphile words and descriptions usually act like they're at a country club sipping 100 yr old wine and eating fancy cheese, trying to constantly outdo each other to feel better and more important than the next person.
If I was referring to a cone driver as being in the category of "fast", the main indicators in the TSP realm to me would be high BL, Qms along with low Le, Qes, Mms, Rms and Fs. This is of course relative to the practical bandwidth limitations and intended application of the driver.
Ideally, the so called "fast" speaker would have infinitely short rise time and decay. Low THD and IMD are related performance factors. With a multi way driver arrangement that is considered to be "fast", the summed acoustic impulse response of all drivers (and xover) working together as a system is what counts. It would faithfully follow a transient perfect square wave. Its the combination of parts needed to work in unity which define a so called "fast" speaker. The behavior of individual components and drivers alone isn't so much as important.
If I was referring to a cone driver as being in the category of "fast", the main indicators in the TSP realm to me would be high BL, Qms along with low Le, Qes, Mms, Rms and Fs. This is of course relative to the practical bandwidth limitations and intended application of the driver.
Ideally, the so called "fast" speaker would have infinitely short rise time and decay. Low THD and IMD are related performance factors. With a multi way driver arrangement that is considered to be "fast", the summed acoustic impulse response of all drivers (and xover) working together as a system is what counts. It would faithfully follow a transient perfect square wave. Its the combination of parts needed to work in unity which define a so called "fast" speaker. The behavior of individual components and drivers alone isn't so much as important.
> Can we measure "Fast"?
If we can identify it from listening alone then it is straightforward to measure since we can measure more accurately than we can hear. So what is an example of a fast speaker and a slow speaker for us to measure (or look up existing measurements). The reasoning about why one is faster than the other should then follow in a fairly straightforward manner from the differences in the transfer function. This assumes the difference is not due to different amounts of audible nonlinear distortion which, if it was, would make it relatively unimportant for high fidelity speakers in normal use and hence likely not worth much consideration.
It was previously postulated that light membrane has something to do with fast, that is perfect transient response. But suspension, motor strength are factors too. Tweeter with heavier membrane but adequately stronger magnet/motor can have the same acceleration and transients.
That asymmetry must display other measurable manifestations. 2nd order harmonic?
If you wish, why not.
I have noticed big difference in dynamics of various speakers, but was never able to measure it.
My general observation, and others too i believe, is that more efficient the speakers are, more dynamic they appear to be. However, i have no data to prove it.
Some things are hard to measure, almost imposible, like stereo separation. Soundstage.
I have noticed big difference in dynamics of various speakers, but was never able to measure it.
My general observation, and others too i believe, is that more efficient the speakers are, more dynamic they appear to be. However, i have no data to prove it.
Some things are hard to measure, almost imposible, like stereo separation. Soundstage.
Rise times decay times dissapation of stored energy.mass excitation.reasonces.its all there.but just relax and enjoy the music.
My working hypothesis is that a 5-6khz bump will enhance perception of sounding "dynamic" -- based on my zoo of speakers. A dip the opposite. Of course one could subjectively test this with the EQ in one's phone nowadays.
Have you not heard a good electrostatic loudspeaker before?
It very obviously has that character when compared to most traditional designs. (..of course with multiple problems as well.)
I'm always fascinated by the various results of drivers and subjective responses along with those few times when others try to correlate objective measurements with those subjective descriptions. I'm not sure any really "prove" (or disprove) a correlation, but I can still appreciate the effort to attempt it; and really - it's quite a lot more than most others (including myself) do on this forum.
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I'll do you one better, I've built plasma tweeters.