Speaker "Speed"

[RayDunzl]

Not that long ago a member (sorry can't remember who) posted some graphs of measured transient response vs transient response calculated from measured frequency response. The graphs were extremely similar.

Me.

https://www.audiosciencereview.com/forum/index.php?threads/impulse-response.1765/#post-44352

https://www.audiosciencereview.com/forum/index.php?threads/impulse-response.1765/#post-44440

 

[detlev24]

[...] Frequency response is pretty easy to interpret, but I'm not sure to too many people can characterize slight differences in phase response or impulse response except to identify 'acceptable' or 'not-acceptable'. Nevertheless, I think phase response is under-rated when it comes to assessing system performance.

Audibility of loudspeaker group-delay characteristics (see free "Access to Document")

(6) Conclusion:

"[...] However, the results could be interpreted to say that the loudspeaker impulse responses for which differences were not heard in this exaggerated arrangement are sufficiently short and that the group delay probably is not a factor in creating audible effects in sound reproduction."

 

[RayDunzl]

The information captured in a transient response measurement is also captured in frequency and phase response. Frequency response is pretty easy to interpret, but I'm not sure to too many people can characterize slight differences in phase response or impulse response except to identify 'acceptable' or 'not-acceptable'. Nevertheless, I think phase response is under-rated when it comes to assessing system performance.

My Martin Logans have the ability to throw "flat" phase to the listening position within the range of the panel.

I'd be interested in seeing someone else post a phase response (without some special gating or windowing) that doesn't slope down dramatically from left to right.

Martin Logan reQuest, 12" sealed woofer, electrostatic panel, crossover at 180Hz, at the listening position 10 feet away, in a room with no special treatments.

In contrast, the JBL LSR 308 graph won't fit in the window...

0 degrees at 100Hz and minus 13,138 degrees at 10kHz.

Showing a wrapped view of the JBL copared to the unwrapped view of the ML, every "wrap" is another 360 degrees down.

Black - ML phase unwrapped
Brown - JBL phase wrapped
Green - JBL unwrapped (example)

 

[q3cpma]

My Martin Logans have the ability to throw "flat" phase to the listening position within the range of the panel.

I'd be interested in seeing someone else post a phase response (without some special gating or windowing) that doesn't slope down dramatically from left to right.

Martin Logan reQuest, 12" sealed woofer, electrostatic panel, crossover at 180Hz, at the listening position 10 feet away, in a room with no special treatments.

View attachment 95135

In contrast, the JBL LSR 308 graph won't fit in the window...

0 degrees at 100Hz and minus 13,138 degrees at 10kHz.

Showing a wrapped view of the JBL copared to the unwrapped view of the ML, every "wrap" is another 360 degrees down.

Black - ML phase unwrapped
Brown - JBL phase wrapped
Green - JBL unwrapped (example)

View attachment 95141

The S360 looks quite clean:

 

[RayDunzl]

The S360 looks quite clean:

Measure at 10 feet in a typical room and get back to me.

That's where I listen, so, that's where I measure.

 

[MarcT]

Apologies in advance if this turns out to be a silly question.

Are there any metrics for the transient response or "speed" of a speaker? Subjectively, certain ribbon speakers I've heard have reproduced cymbals and strings with a faster attack than otherwise comparable tweeters.

I've seen it being described on other forums as the ability to accurately follow a square wave, but I've no idea if this is an accurate definition. I'm also not sure if the relevant metrics are already present in Amir's measurements.

Yes, I've also been wondering about if, and if so, how measurements can tell us or confirm it when we perceive one speaker as having a more immediate sound of a really sharp, loud rim shot or other extreme dynamic impulse. It seems like not all speakers would be equal in being able to replicate such transients, but I don't know what measurements would tell us that. I also don't understand what measurments might inform us about the relative dynamic impact(commonly called "slam") various speakers have, in comparison to each other.

 

[thewas]

My Martin Logans have the ability to throw "flat" phase to the listening position within the range of the panel.

I'd be interested in seeing someone else post a phase response (without some special gating or windowing) that doesn't slope down dramatically from left to right.

You gave the answer yourself, with their high beaming they reduce the room influence at the listeners position that makes the phase response look like that with conventional loudspeakers unless you gate them.

 

[restorer-john]

Yes, I've also been wondering about if, and if so, how measurements can tell us or confirm it when we perceive one speaker as having a more immediate sound of a really sharp, loud rim shot or other extreme dynamic impulse.

A toneburst does the same job, but shows individual cycle under/overshoot and as long as you mic it up close, the room refections are obvious, separate, and the quality of the speaker in terms of transient ability can be assessed at various elevated power levels and frequencies without potential driver damage.

It's visually a nicer apples to apples comparison IMO.

 

[AnalogSteph]

In contrast, the JBL LSR 308 graph won't fit in the window...

0 degrees at 100Hz and minus 13,138 degrees at 10kHz.

Ahem. What we're seeing is some plain ol' delay. As the LSR308 is a DSP job, expect a few ms extra just for A/D + DSP + D/A. You'd have to null that out first.

 

[NDRQ]

The longer decay was present on Revel 1 and Panotsi 2. Again, it was very subtle, and not something I'd notice if I wasn't doing a back-to-back A/B comparison.

Maybe hard to notice in a back-to-back comparison, but it would be really big difference if u listening one speaker for 1-2 month and then changing to the other. The fine, subtle differences usually cant be heard in a short testtest, you can only hear if theres a big treble spike, bass bump, or stg similar kind of thing.

 

[RayDunzl]

Ahem. What we're seeing is some plain ol' delay. As the LSR308 is a DSP job, expect a few ms extra just for A/D + DSP + D/A. You'd have to null that out first.

*presses button

No change in the phase display noted.

---

As the LSR308 is a DSP job, expect a few ms extra just for A/D + DSP + D/A.

I'll set up a Left = ML and right = JBL and see how much delay there is in the speaker, since that isn't a bad thought, and I don't know...

 

[andreasmaaan]

View attachment 95161

*presses button

View attachment 95162


No change in the phase display noted.

Something is wrong though. I’ve never seen an in-room measurement that differs at all dramatically from the anechoic phase response of the speaker, at least not above the modal region. You should be seeing 2-3, maybe max. 4 phase rotations there, not dozens of them.

 

[andreasmaaan]

Maybe hard to notice in a back-to-back comparison, but it would be really big difference if u listening one speaker for 1-2 month and then changing to the other. The fine, subtle differences usually cant be heard in a short testtest, you can only hear if theres a big treble spike, bass bump, or stg similar kind of thing.

I invite you to send me a sample recording of your choosing, one most likely to reveal the kind of audible difference you’re talking about. I’ll then run it through the filter and send it back to you. Then you can listen to the two files (sighted), just for curiosity’s sake.

Or if you want to really test your beliefs, you can use the files to do a controlled test to see if you can identify the difference, taking as long as you want (months even, if you prefer).

What do you think?

 

[richard12511]

Maybe hard to notice in a back-to-back comparison, but it would be really big difference if u listening one speaker for 1-2 month and then changing to the other. The fine, subtle differences usually cant be heard in a short testtest, you can only hear if theres a big treble spike, bass bump, or stg similar kind of thing.

Actually the opposite is true . It’s much easier to notice tiny differences when switching quickly back and forth.

 

[ppataki]

I didn’t read the thread, but there should be a clear conclusion!

Measure the impulse response (or any signal that can be transformed into an impulse response, eg a sweep). That measurement will contain a full characterisation of your loudspeaker’s transient response (within the limits of your measurement setup, ofc).

It’s really that simple

@andreasmaaan
Can you explain please how to interpret the IR curve for transient response?
So for example this IR curve, does it have good or bad transient response and why?
Many thanks

 

[steve59]

I'm going to go out on a limb and suggest from a pure listening position dynamic range would make 1 speaker sound faster. My kef r105/3 at 93.5 against my VA beethovens at 86db {the efficiency ratings gotten from review measurements) with the same amp turned so either pair was playing to 90 db peaks made the beethovens sound polite and plodding while the kef's sounded like they were attacking each song. I expect the way a speakers bass reacts to a room will have some effect on perceived speed also.

 

[JohnnyAudio]

Magnet size. Since a speaker is a motor, a large magnet will give more torque and speed, especially nice on the return stroke.
So a powerful bass note sounds powerful and when it's over, it stops without any linger.

 

[maynardewm]

Pardon my naivety, but if most agree that speed is an important property in the quality of a speaker, and there’s no agreed upon way to measure it, why do we rely so much on measurements? I know on ASR, they are so big on measurements and basically saying if you can’t measure it it’s not real, but this seems like a pretty fundamental example for how not everything can be measured.

 

[Jim Taylor]

... if most agree that speed is an important property in the quality of a speaker ...

"Speed" (as used in audio) is an example of subjectivist pseudo-science. It's similar to "liquidity" ... meaningless ambiguity.

not everything can be measured.

We can't measure the dimensions of Russell's teapot that is orbiting the sun between Earth and Mars. It is a fallacy to deduce that we therefore cannot disprove its existence.

Jim

 

[Beave]

Pardon my naivety, but if most agree that speed is an important property in the quality of a speaker, and there’s no agreed upon way to measure it, why do we rely so much on measurements? I know on ASR, they are so big on measurements and basically saying if you can’t measure it it’s not real, but this seems like a pretty fundamental example for how not everything can be measured.

First, define precisely what you mean by "speed." I have a hunch that if you are able to define it precisely, then you will also find there is a measurement for it. On the other hand, if you can't define it precisely, there probably is no measurement for it.