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Amir, How about speaker driver tests?

Juicehifi

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Driver tests would be very valuable to basically anybody who are into DIY. And for me as well. Speaker drivers are far from perfect,

Have you considered starting to measure speaker drivers? The late guru Siegfried Linkwitz did a few measurements that could serve as inspiration https://www.linkwitzlab.com/
 

amirm

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The system I have purchased does include the full capability for driver testing although may require some more software licenses. For the short and possible medium term though, I have so many speakers to measure that I don't see getting down to driver testing.
 

MZKM

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The system I have purchased does include the full capability for driver testing although may require some more software licenses. For the short and possible medium term though, I have so many speakers to measure that I don't see getting down to driver testing.
HiFiCompas does driver testing and AudioXpress has the Klippel system to measure drivers. Let’s just say the latter is way over my head, I don’t understand any of the graphs, example:
20190130193920_Figure7-DaytonAudioRS180P-8Midwoofer.jpg
 

hardisj

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HiFiCompas does driver testing and AudioXpress has the Klippel system to measure drivers. Let’s just say the latter is way over my head, I don’t understand any of the graphs, example:
20190130193920_Figure7-DaytonAudioRS180P-8Midwoofer.jpg

This is an example of how much the suspension changes as the driver coil moves in and out. It's stiffness of suspension as a function excursion; Kms(x). The black/blue line represents measured response and the dashed line is the opposite; you want the two two overlay which would mean the forward/reverse stroke is symmetrical (the suspension doesn't shift in any way with excursion and helps to hold the voice coil centered in the gap). From this graph you can see assymetry in the forward/reverse stroke as the excursion gets above 2mm which would add to the 2nd order distortion component and higher components around F(s).

To get this data you need (at the very least) the LSI module. That is the only module that will provide you data as a function of excursion. The LPM module would be a nice addition but isn't absolutely necessary (I used to use Smith & Larson's Woofer Tester to get me that). But to get more accurate data you want to use a laser with both these modules. I'll be using all of these. ;)
 

Green_X5

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If this happens, Thiele-Small parameters of JBL 305P MKII speakers please. ) I really want to transfer this excellent speakers to the three-amp case with the addition of woofers, but I have no way to measure them. / There is no data for calculating a closed box.
 
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