driver diagnosis

[agrobler]

Hi

We had a Jennifer Warnes: The hunter track at normally loud levels... other test cd's are usually fine there, but the bass drum ?came and the four 6.5" midbasses went a "little" wonky - one makes a fairly loud drrrr drrrr sound when it plays the others make quite soft drrr drrr sound whilst playing... only on bass, not scratching in the mids... There was no tap at the sound of the note...

The track must have very low frequencies... mine go down to 40 - ish and it didn't sound extra-ordinarily loud - what is it about that track?

Drivers are no-names from the far east that perform better than suggested in a 38 l "hopefully" sealed enclosure

I've looked at repair web-sites, they seem to only offer a reconing and surround repair - no voice coils only it seems...

Thanks!

the voicecoil doesn't seem to scratch when pushed in or out, except if you press on one side of the cone only.

SO is this a separated voice coil?, no smell of burnt resin (has phase plug so no dust cap to get in the way of smell) or a centering issue?, the spider didn't seem loose... could check more carefully... Should probably check that the vc leads didn't get "stretched / repositioned" and are now touching the cone?

 

[lndm]

There might not be anything wrong with your speakers. The sound you heard might have been the voice coil formers bottoming out. There might not be any damage.

This track is known for this and has been used as a test track.

Are you interested in getting higher levels out of your speakers?

 

[agrobler]

Hi

It might have been, but I'm not sure that that is the same sound it has been making since - it made this noise afterwards with low frequencies at low volumes... as if resonances rather than excursion causes it - I think. I did remove drivers and re-shaped the voice coil leads - they seemed to have been stretched a bit - or just re-positioned. This fixed it for all drivers, but only temporarily for the worst one.

So I think it is the leads slapping, the one that continues to do so (re-shaped them again, will see what happens) may have been stretched or permanently de-formed i.e. stiffened - and will now start resonating significantly at certain frequencies because of added stiffness... maybe very cheap braided leads... or the spider got stretched and excursion now slightly less controlled - no scratching though...

Thanks for info... but is it just eq'd that way, or is it a natural recording with big mike?

Not really, a new audio buddy is toying with active and wanted to listen to it... had some test cd's, a beer....

 

[lndm]

Yes, there's nothing like a beer and a couple of mates to make you want to stress test the suspension.