Tchaikovsky wrote his Fourth Symphony as he battled personal demons; the act of writing the piece reportedly helped him achieve some semblance of sanity. Tonight at 8 at Severance Hall, the Cleveland Orchestra performs his Fourth Symphony. The program also includes Copland's El Salon México and Paulus' Grand Concerto for Organ and Orchestra. Arrive an hour early for a pre-concert talk with guest speaker Meaghan Heinrich, chair of the woodwind, brass and percussion department at Wisconsin Conservatory of Music. The program repeats at 8 p.m. tomorrow and 3 p.m. on Sunday. Consult the website for ticket prices. (Niesel)