Anyone familiar with NS10 tweeters disassembly?

6V6dude

Member
2014-09-09 11:07 am
I wonder if anyone ever disassembled Yamaha NS10 tweeter for dome replacement etc. My dome seems to have come unglued partially on one side. When I run frequency sweep it buzzes at certain frequency but when I push lightly on the dome side edge it goes away.
I've started to open it up, took out the three screws but it wasn't coming apart so I've stopped because I have no idea if the front plate is also glued together, thus me forcing it apart could rip out the coil and who know what else is in there.
Any advice would be appreciated, thanks.
 
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Some photos of the NS 10 tweeter (JA 0518A, woofer JA1801) show remnants of glue - they seem to be indeed glued in place despite pins which center the coil/diaphragm and screws being in place. I'm not sure if that's traces of repairs or getting the tweeter airtight towards the back. After removing the screws it should be possible to pry it carefully open with a screwdriver between front plate and magnet. You should try not to harm the plastic front plate because a non-flush re-mount of the plate increases the distortion.

(not my photos)
 

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6V6dude

Member
2014-09-09 11:07 am
Thank you for the photos! Looks like it separates completely including the coil. And if it's also glued that's a bit scary.
I've been looking closely at the tweeter and the photos, from what I see, it looks as the dome membrane is glued around the edges from the top. I might attempt to put some glue on the edge if I can get to it. Not only there is the plastic plate in the way but I thing the spot that has come unglued is right under one of the lead wires which I all ready had to repair once too.
In the mean time I'll try to ignore the occasional buzz as long as I can before taking the risk of trying to fix it. But getting ready for the event when it comes -)
 
The buzz can also be a leak. The sound pressure from the inside of the speaker could go out through a little gap between diaphragm or front plate and magnet, causing the tweeter to flutter at a certain frequency, likely not in the highs (if it is a leak). To test it, use a frequency generator (cell phone + app is enough) and the speaker completely assembled. Go through the whole frequency range and find at which frequency it happens. If it's happening at some frequency in the bass, you just have to seal the tweeter between the magnet and the front plate. To do that you could use silicone or acryl. Generally something which is reversible in case you have to repair something else.
 

6V6dude

Member
2014-09-09 11:07 am
Yes I did the sweep when I've discovered the buzzing. I can't remember exactly the frequency but I think it was somewhere around 1k. It's most obvious if I play plain recorded guitar track so I guess that's around the 1k.
I thought the loose dome was vibrating at that spot but if there is an air pressure being created than yes I agree that's probably it. I just need to see if I can get some soft glue in there, it is a difficult spot. If it gets worse I'll have to take the chance. Thanks!