Recently I suddenly heard a voice coil rub on my right speaker when I got up close. Took a look and there is nothing wrong with the internal. Only happened during excursion on bass heavy songs. Took awhile to found out that the cone is abit mis-aligned, it’s more towards the outside which made it easily hit it’s limit. The spider is not sagging nor anything at all. I posted both pic of both my speaker and you can see the distance between the phase plug and the shim.
I’m finding it hard to “spot the difference” in the two photos but did once experience an issue with some aged Royd speakers where the cone had “dropped” ever so slightly.
To resolve this, I simply undid the screws and rotated the speaker driver through 180degrees, so the bottom became the top, if you see what I mean.
This cured the issue which hasn’t recurred since.
I found whats the issue, the spider went loose. So it is bending outwards by around 0.1mm. I stuffed foam inside it to kill its internal cabinet volume and to make it excursion less, tried to make it gain back control from the back pressure. Not worth fixing since it is not detaching or anything. Just the fact time got one step in front of my woofer.
