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step response is a important part to show speed of speaker that is good enough for ITD. See measures

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bennybbbx

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I figured as I still had some spare time, I could go "one on one" with Benny for another night or I could spend the time cleaning up that Dunlavy paper. I chose the latter, see attachment. No offence meant, Benny, I just figured that document would benefit more people.
Thanks to Google for their free OCR software in Google Drive -> Docs.

So here's: Loudspeaker Accuracy by John Dunlavy

(I have to chuckle about the passages about "A wide "sound stage" :D, I don't disagree however, Toole might have a different opinion)

I read and i find this on page 3. so step response is usefull too see.

A complete set of accurate measurements, to be meaningful, must include the following:
1. Impulse response
2. Step response
3. Amplitude Vs frequency (frequency response)
4. Phase response Vs frequency (may be inferred from the impulse and step responses)
5. Waterfall
6. Energy-time response
7. Impedance Vs frequency
8. Radiation patterns, in both vertical and horizontal planes, at several meaningful frequencies
9. Non-linear distortion (harmonic and I.M.)
 

kimmosto

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Ideal timing = minimum phase total acoustical response = very close to 0 ms excess group delay at least down to 100 Hz is natural target in speaker design. MP response is not easy to implement in practice, and audibility depends on music material / instruments so it's quite often one of the first features to compromise. Excess group delay is quite short / ok in typical 2-way, but already 3-ways start to suffer dynamic and timbre problems. For example every 3-way with steep IIR XO slopes what I've heard has failed to reproduce piano with proper hammer force. 4-ways are probably worse etc. Customers listen something else or never heard actual instrument and proper reproduction of it or believe too much in sloppy science so manufacturers have been lucky so far.
 
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bennybbbx

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It's just NOT "a important part to show speed of speaker that is good enough for ITD" :)

I have now done another confirm that it show speed of speakers. In Rew it is possible to use EQ to correct a speaker. and from this correction can create with the button "generate measurement from predictat" a calced result how the step response and FR then look when apply the eq. for the LP filter is only 6 db possible but you can see the FR is very simular. for the HP filter i use 100 hz 24 db. so rise time should when the step response show only FR near same. but it is not. so wy the kali is slow. i shift the kali measure so it begin at same is the iloud mtm. here is the non EQ measure
the EQ correction in RW is not so good, work sometimes not. i can for the jbl not create a EQ for this target curve, but is precise enough to see that not only the FR change the step response

the settings.jpg
r ?
freq compare.jpg

step response iloud mtm.jpg


this is the complete step response of the kali with same target curve as for iloud mtm.


step response kali EQ.jpg


kali 6 LP 1. version, eris 3.5, iloud mtm step response after target curve EQ

eris 3.5 step.jpg
 
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