Climate control and Pianos: A conversation with Sam Bennett (Piano Works in Duluth, GA)

I'm very concerned about my Southern USA students' pianos that are subject to warbling unisons, or wavy, beating octaves. A case in point is my Kentucky Online pupil who owns a well-regarded Charles Walter upright that was tuned about 5 months ago. Yet it now has "beating" notes due to extreme vacillations of humidity in…