Planar Speaker Asylum: Re: Magnepan SMGa repair kit by Ian Weitzel

SMGa repair kit from Magnepan (Freephone no on their website I think) costs $30 as I recall.

It's really a tweeter repair kit (does both speakers) - consists of a spool of aluminium tweeter wire, alu solder, new termination block for connecting speaker wires to crossover wires, acetic acid-free sealant for protecting joints from atmospheric corrosion and a can of Milloxane #551 for painting over the wires after fixing them. (that's the stuff that freezes and so doesn't get shipped during the Minnesota winter).
The user has to supply his own 3M #77 spray adhesive to fix the wires in place before applying milloxane, (but see postings on this site regarding using a small electric current to fix the wires rather than #77) and also his own acetone for removing the old glue and wire (many postings on this site).

There is one wire for both the mid and the bass. I don't know the gauge (I think there was some traffic on the subject here a while ago). When speaking to Steve Whiney a year or two ago, he opined that once the bass wires had corroded the speaker was effectively past economic repair - I got the distinct impression that they were reluctant to sell me this.
If you can repair the mid-bass I would recommend getting enough Milloxane to treat them also, since as well as increasing the adhesive grip of the mylar on the wires, it acts as a UV screen to stop damage by sunlight. SMGs were manufactured before milloxane was around, which is one of the reasons they deteriorate.

Anyway, give Magnepan a call - you'll probably end up speaking to Margaret in the parts department. She's very good and will advise you as to your best course of action.