I wonder if the felt on the mid is used as some kind of diffraction aid, and is covering the actual surround? As lighter fluid dissolves glue, I would be reluctant to use it on the surrounds. Distilled water/vinegar seems like a gentle way to begin.
I believe the felt surround of the Mid is its suspension, without anything behind it.
I would not use anything acidic (like vinegar) on old speakers >
Their old & delicate 'flexible wires' can be attacked, even by fumes.
In fact, avoid all strong solvents. Neutral products are the best way to go.
I would not use anything acidic (like vinegar) on old speakers >
Their old & delicate 'flexible wires' can be attacked, even by fumes.
In fact, avoid all strong solvents. Neutral products are the best way to go.