No. I didnt go thru all... as long as they showed some real distortion data for DIYAudio non-believers, it is good for my purpose. I already made a lot of driver distortion measurements. Remember this started as comment re Geddes.
But, I never save data and write about it. Just doing it for my own knowledge and curiosity.
-Richard
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This is interesting. Because sometimes after several years one might like to return to old measurements, with new ideas, and then the brain memory storage might not be enough.
It is easy to do test again or do a before and after test. But I never have any audio or speakers That long to want to keep archive its data. But, I should not say Never - that is an exaggeration. But with computers, I do save something unusual or novel or other wise interesting. But it isnt much.
I just agitated about speaker disortion because of Geddes comment....
Would like to discuss more about the importance of less wide dispersion and CD.
-RNM
I just agitated about speaker disortion because of Geddes comment....
Would like to discuss more about the importance of less wide dispersion and CD.
-RNM
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You are on a mission then
I find that the problem is in reading the TOC and not in the storage capacity
George
On that speaker, yes.
Ditto for another one that data is provided (see pages 34, 35)
https://www.klippel.de/fileadmin/kl...ervice/Measurement Service Report example.pdf
But it’s not safe to generalise (a good reason to use your AP to test a large sample of drivers)
Only the agitation part.
Remains the constructive one.
George
I would not assume ALL do that but most do.
yes. Now its up to others who are interested to measure their speaker distortions and do more study of distortion and dispersion effects and CD.
In the process, (this is the constructive part) you will find out for yourself why JBL M2 is exceptional and accurate system. I have already said why IMHO.
THx-RNMarsh
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Thank you George as usual. This data supports vanishingly small distortion above a few 100Hz, I have some ideas on how to simulate this without impossible maths.
Richard, are there any distortion vs frequency and vs signal level diagrams published for the drivers of the M2 ?
George
George, not that I could find with a lot of looking no reviews that do either. BTW Stereophile does not do (or rarely) these tests on speakers either.
As you are that rare animal that actually has some M2s and the gear to test them, hopefully you can get us some measurements of their distortion performance?
Hi Scott
Unless you want to sharpen your pencil 😉 from what I have seen in Klippel, ALMA and other research entities papers, the simulated and the experimental data points match quite well. The loudspeaker model they have developed can be utilised.
As usual the issue is in assigning realistic values on the model components.
https://www.klippel.de/fileadmin/kl...urement of Loudspeaker Suspension_Klippel.pdf
https://www.klippel.de/fileadmin/kl...linearities?Causes,Parameters,Symptoms_06.pdf
https://medias.ircam.fr/media/slideshows/2015/11/26/AntoninNovak_2015.pdf
George
I should have figured someone did it, time is limited and I only have peripheral interest in this. I would never listen to music at 105 dB, ever, just trying to get a focus on the physical realities of the problem.
Measurement data for the woofer 2216Nd 15
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=63736&d=1417800709
No data for the compression driver D2430K, only the applicable patent
DUAL COMPRESSION DRIVERS AND PHASING PLUGS FOR COMPRESSION DRIVERS
If one wants to purchase the drivers for testing😀
JBL 2216ND-1 Woofer for 4367 #320-0045-002 - Speaker Exchange
JBL D2430K Tweeter for JBL M2 #5032754X - Speaker Exchange
for this, I find the Klippel poster very informative (sorry for relinking)
https://www.klippel.de/fileadmin/_migrated/content_uploads/Klippel_Nonlinearity_Poster.pdf
George
Whoo! Six hundred bucks for the woofer, in proud JBL tradition. 🙂
As for the CD: "M2 serial numbers are required to purchase." 😉
Jim, take a trip to Mexico 😀
Hint for educational purposes only: Reverse engineering (modern route: 3D scan the real thing, send the file for 3D printing)
George
Attachments
I've done it before, just get a friend to provide what you need. "Help, my gaffer just pushed a piece of scaffolding through my speaker". 😉
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