These 3 ply shells are mint inside. Got them with all original heads...I think I'm the first one to see inside them since the guy who sealed them up in Japan 45 years ago....
They are untreated, no paint, no lacquer.
Is it best to leave them alone or seal them with something?
Will any interior treatment add to the performance of these old 3 plys?
I assume granitone and lacquer each do something different to the tone. Anything noticeable?