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

I think there's a big gap between a speaker that sounds fast, and a driver that IS fast.

I mean, there's a lot of reasons for speakers having more detail or jump factor. The actual transient response of the drivers used does not really contribute to all of it.
How the speaker mates to the room, and frequency response I think are probably the first two things the casual listener associates with speed.

That's fine, nothing wrong with that since the end result is what matters.

I think a lot of what you are writing about, mijostyn is actually related to room interactions.

Your writing, while accurately portraying how dynamic drivers work makes a leap I don't feel comfortable following.

A dynamic driver can have a lot more dynamic range, smoother frequency response, better low frequency and lower distortion than a planar speaker attempting the same. What it won’t do is interact with the room the same way. Genesis got around this by making towers of 12" drivers. :)


Snell mounted the woofers as close to the floor as possible.

The final result is always a matter of speaker and room interactions, but the idea that planar speakers are measurably faster is not true.


Best,

Er

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

That is, the waterfall plot is very clean and very short, without ringing.

I rarely hear the square wave definition used, but sure, some do.

The square wave has more to do with time/phase accuracy, and something that can be corrected for via DSP.

It is certainly a very rare thing to have a speaker that can replicate it with any sort of accuracy. :)

It usually refers to the ability of an attack (the first arrival) to startle you, such as with a kick drum or cymbal. It is also about the detail which can reach you at your seat.

In my mind, this is an artifact of tone, not actual driver speed, but since panel and cones couple so differently to a room, panels are often described as fast, while cones as slow. This is not really what's going on, but whatever. :)