OK, I admit posting on this before, but no workable answer received and the situation is changing...

I got a pair of cosmetically perfect LE15A about 18 mths ago, they had similar voice coil resistance at the time ('bout 6.7 Ohms if I remember right). With time, one started to behave strangely, loosing some apparent efficiency. Also, it's coil resistance went up to 9 Ohms, and testing in free space showed that it had 'lost' it's expected impedance max at resonance frequency.

Now it is extending to the 2nd driver also loosing it's peak when tested, but the coil resistance is unaffected. This leads to some difference in L-R dynamics even when working on the L-pads setting to balance the levels.

THere is no sign of voice coil rubbing or anything, someone suggested that the magnets might be loosing power, but I can't see how that would affect coil resistance and lead to the loss of the resonance peak (yet I dont understand much of the physics of these things).

This is another attempt to fish for ideas on what could be going wrong. Soundwise, I love it (despite the slight L/R difference), but I am hesitant to pay another extra hundreds euros for replacements if it's to get the same problem. Any suggestions anyone?

For info, I use them in combination with LE85 and with original L200b networks (now completely rebuild with new and better components), in home made boxes and circular horns.

Thanks for any suggestion,