Tearing my hair out over a pair of Beovox MS 150s... (8" distortion... midrange issues...)

About four years ago a lovely pair of MS 150s were given to me, they obviously needed reforming but I put them in my garage until I had room for them...

I finally got around to reforming them in the summer of 2018, and used the shimless method of centering the cones.  It went well, but after a while I noticed that one speaker sounded different (did a bunch of troubleshooting to make sure it was the speaker) and recapped the crossover as part of troubleshooting.  Eventually I just started piping stuff through my equalizer to get around the issue... until about a week ago when I stopped noticing an appreciable difference without the equalizer.  Yesterday I noticed a distorted sound coming from the 8" woofer in one speaker (which from here on will be referred to as the right speaker).  I isolated the issue to the speaker itself, which was most prominent on piano music.  After putting the speaker on my workbench and trying to replicate the issue and failing, I put the second speaker right next to it and realized that the left speaker's tweeter seemed to have a much lower output and distorted.

So as it's sitting now, I have one bad 8" woofer, and one bad 3" midrange.  The woofer I was going to send off to Parts Express's speaker repair center for reconing, but with a midrange now bad I'm not sure what do do.

The shimless method...
Does the voicecoil or the coil former rub if you move the cone (carefully of course) in and out by hand?

The midrange can usually be repaired by a skilled and careful DIY'er. Or indeed any speaker repair shop.
The voicecoil losens from the cone. It's a common issue, it starts to distort and will eventually go silent - but still repairable.

Martin

That did have a slight rub to it, and I re-refoamed it (8") last night using shims, the issue still persists . I will take a look at the mid range today and see if I think it is within my capabilities.  What type of adhesive would you recommend to fix the coil to the cone?  I have Epoxy (both rubberized and ridged), superglue, and pliobond on hand.

Epoxy. The slow setting tough stuff.
And a very small amount - there's no room for a thick bead of glue in there.
I use the blue 2-comp. Araldite Standard (24h setting time) for these jobs.

Do be careful with those thin wires running to the solder tags.

Martin

That brand seems to be hard to come by in the US.  Would JB weld's standard formula be an acceptable substitute?

 

EDIT: Well found stuff online saying the steel particles will interact with the magnet (duh). 

Aerochromatic:

That brand seems to be hard to come by in the US. Would JB weld's standard formula be an acceptable substitute?

EDIT: Well found stuff online saying the steel particles will interact with the magnet (duh).

In the US here I bought from amazon for around $8, works phenomenally, very different than JB weld which I’m also very familiar with.

I’ve tried many other epoxies, this has been my favorite.

I wound up getting the loctite Instant Mix (5 minute set, 24h cure) that simply speakers recommends from the hardware store, and it worked well.  I broke the leads from the voice coil on one, but was able to repair it with a single copper strand from a stranded cable.  The only thing I am having trouble with is re-centering the domes in the (magnet channel?) so it does not rub on anything.