What does the term "Speed" mean in a speaker?

Here is a question: if both speakers have the same frequency response, why does one speaker have better speed vs the other?  

Another question: if one speaker uses a 4in. driver for the midrange, the other uses a 6.5in driver for the midrange, and both have the same frequency response, which will have more "speed"?

It's difficult to say since the 4in driver might have better speed in the midrange, but the 6.5in driver might have better speed for the bass.  

Also in general, if a speaker has a tipped up treble response, it does lend to an illusion of having better "speed" especially on the leading edge such as guitar.  Of course having too much leading edge could be a problem too.  

Another way of talking about "speed" is "lack of stored energy."

I supposed that has more to do with "driver break up" or suffering from "impedance anomaly".  Paper cones may have a clean water fall plot, but an aluminum cones may have "faster speed" but may not look as clean on the water fall plot.  

Of course having "faster speed" does not always mean "better".  There word "speed" in this thread seems to have a lot of different interpretations.  Different people seem to have different impression of the word.

I don't understand why manufacturers don't post 0-60 and 1/4 mile times?

It would make speaker selection much easier.

You can't be serious.  

Speakers with better transient response are more revealing and can easily be made to sound crappy with bad or poorly set up equipment which I think is why some people have a jaundiced opinion of them particularly horns which are also not easy to design.

I am not quite sure this is entirely true.  A driver that has better transient does not mean it should have more detail or more revealing.  Better transient allows better micro-dynamic or macro-dynamic or both, BUT dynamic is not the same as detail or at least it's not a one to one exact.    

Now on the other hands, if a driver has more "resolution" then it will have more detail, but a more accurate characterization is to say the driver will "reveal" more details.  It shouldn't create more details that was not on the tape in the first place.

Transient and resolution are mutually exclusive that is one driver can have either or both.  Having one does not automatically also having the other.

Aluminum driver is usually perceived to have more "details" but a lot of that comes from it upper frequencies which tend to have a lot of break up and people sometimes interpret excess high frequencies as "detail".  And if the designer does not address the break-up, then aluminum will sound "crappy", but is it the driver fault or the designer fault?  I personally have used some cheap aluminum driver and expensive paper driver, and although the aluminum may appear to sound faster, the more expensive paper driver reveals more details, more natural detail.  So go figure.  

As for speakers that "sound crappy with bad or poorly set up", I think a lot of that comes from final implementation.  I've had the Thiel CS2.4 which is very revealing but it never sounds crappy even on bad recordings.  Speakers that sound crappy on bad recordings tend to have excessive energy on the high frequencies or some weird frequency response.  

Has anyone heard Martin Logan speakers? The electrostatic panel plays the mid and treble while the woofer plays the low frequencies.

I always felt like the woofer was slightly lagging behind as if the bass and the upper frequencies were playing slightly different tune.  The bass was in effect "slower" vs. the mids and high frequencies.

Also, most of the time, speaker frequency responses are measured in steady-state response which more or less erases the transient response, but the "speed" lies in the transient response.  So two speakers can have the same freq. response but one may be faster than the other.

May be a step response measurement can tell you the "speed" of different speakers because it preserves the transient information.

I think it falls into what the Brits refer to as PRaT - Paced Rhythm and Timing. Of course Prat is also British slang for:

1. an incompetent, stupid, or foolish person; an idiot.
2. 2. a person’s buttocks.

I supposed this is another dumb joke.  Maybe you're number 1?

"You can’t be serious."
https://www.thefreedictionary.com/read+between+the+lines

Don’t get out much? Sorry, couldn’t resist.

"Maybe you’re number 1?"
https://en.m.wikipedia.org/wiki/Snowflake_(slang)#Generation_Snowflake

Oh my, are you one of these? If not, refer back to above.

1. Stop wasting people time.
2. Stop making dumb post.
3. Maybe you should get out ... of here lols.  

resolution and transient response are very closely related. By dynamic I do not mean loud. I mean snap.

Yes, but they may not be one to one exact. A high end paper driver may have more resolution and a low end aluminum driver may have more transient but the aluminum driver may not have the resolution of the paper driver.

Snap could mean a lot of thing. A speaker may have a lot of snap but it does not mean it has a lot of resolution. I can fine tune my speaker to have tighter bass and extra energy in the higher frequency to give it more snap but it may not have more resolution.

When a speaker has "speed" it's approaching the sound of real, life like, sound

Designing speaker is a compromise - some are optimized for speed (dynamic), or soundstage, or musicality.  Some $80K speakers can have a huge soundstage but lack musicality.  Some are optimized for speed but soundstage may lack bloom.  And so on ...

I do not put electrostatic and planer speakers in the same category as push-pull standard types of speakers

That may be true, but conventional drivers are transducers nevertheless - they convert electrical energy to mechanical energy hence by definition they are transducers. And fundamentally there’s not much difference between electrostatic panels and conventional drivers.  They might be different but not fundamentally.

Most speakers are not time cohesive and nobody seems to care or notice.

Just because nobody seems to care does not mean it does not matter.  Just because if something has not been proven, it does not mean that it's not true.  

Hold on Andy. That is a mistake. Yes they are all transducers but their ability to function in air is quite different. ESLs and horns are a better impedance match to air and transmit sound waves more efficiently. Dynamic drivers have to work harder to get the same results. ESLs work entirely differently than conventional speakers. First, there are no magnets. ESLs are capacitors conventional drivers are not and represent an entirely different load to the amplifier. Designed correctly their transient response is superior to conventional drivers because the moving system has far less inertia and is a better impedance match to air.
Planar speakers are somewhere in between. IMHO in spite of the compromises you have to make ESLs rule as long as you can make them. I have personally not heard a conventional speaker sound as convincing. Some say well designed horns can do it. But I am still waiting to hear one that does.

OK, you're right.  Opposite attracts :-)

By the way, horns use conventional drivers so they are probably the same.