In my last post I explained how I had acquired a pair of Tannoy PBM-8 studio speakers. I also discussed the condition of the speakers. Since then I have started the process of refurbishing the units, and the progress has been quite good so far.
Speaker cabinets are almost always lined with some sort of anti-echo insulation. In the case of these PBM-8s the insulation looks a lot like and old style of upholstery padding or overly thick carpet pad. There is all sorts of advise on the Internet about what to use for speaker insulation, and much of it is questionable.
I could not find a source for this sort of insulation, which is not too surprising, so I consulted with a speaker expert. He suggested looking into simple polyester batting that is readily available from the local big box hobby and sewing store. The JBLs that I repaired a year or so ago had what I believe to be fiberglass rather haphazardly stuffed inside. Back about 3200 years ago I used shag carpet in a set of speakers that I made. That worked very well, and the speakers still sound pretty good.
However, I decided to explore the expert’s advice and went over the big box store and found a large number of goodies that should do the job. I bought a bag of a very cool foam, and I will report soon on how well it works.