high speed filming/photographing of cone breakup

[Geoff Howes]

Has anyone tried to photograph or film cone breakup in action using high speed equipment? It seems to me that being able to view it in slow motion would be of benefit to designers of drivers, and help dumbass speaker builders such as moi to understand the whole phenomenon better.

 

[ICG]

Yes, there is equipment to show and measure the cone breakup. Google for 'Klippel', that's a laser measurement system, that even shows the dynamic behaviour (-> changes with the excursion) and the symmetry of the suspension (-> offset).

 

[jplesset]

I recall several manufacturers doing research on this in the '70s, B&W, and others.

 

[fatmarley]

FINECone

Filmed In slow-mo - LINK

 

[Diogenes]

Has anyone tried to photograph or film cone breakup in action using high speed equipment? It seems to me that being able to view it in slow motion would be of benefit to designers of drivers, and help dumbass speaker builders such as moi to understand the whole phenomenon better.

Very common with the better equipped and literate outfits out there that engineer their own drivers as has been noted. If you want to read up more about how it's done the Star Trek term for the piece of equipment used is "scanning laser doppler velocimeter".

Filmed In slow-mo - LINK

That second video isn't showing the cone behavior, but rather is an artifact of rolling shutter. There's good reason why the pros use lasers and not GoPros.

 

[Pano]

Thanks for the link to the FINEcone demo. That's impressive software!

 

[Zvu]

Great stuff Fatmarley.

I'd really like to see Mg, Al or ceramic cone simulation. Materials that, unlike plastic, do not bend that easily and transmit most of the sound rather then absorb good part of it.