Ключевые слова: acoustic, acoustic piano, adjusting, antique, bass, beating, board, broken, builder, business, closeup, equipment, grand, hammer, hand, industry, instrument, key, key frequencies, keyboard, midi, music, musician, mutes, old, pedals, person, piano, piano key frequencies, pitches, precision, repair, repairman, return, service, sound, spinet, steel, string, technician, tension, tension of the strings, tool, tools, tune, tuner, tuning, upright, vintage, wood, work,