<HTML><HTML>Greetings,            Yes, I have had= the following experience: I was in piano tech school practicing tuning in a= tuning booth (we used to call them tuning "caves"). Booth consisted of a so= und proof glass windows floor to ceiling with a glass door. These booths are= actually pianist practicing chambers used in conservatories, but our school= used them for tuning practicing chambers.             I was pra= cticing my tuning. I had been in the booth for 6 hours with a small ventilat= ion fan on. As a green rookie, I couldn't figure out why I was having so muc= h trouble getting the piano's octaves to match. Finally, I was "done". When = I opened the door it was so much cooler and less humid in the hallway. My ow= n breath had been making the humidity to rise all during that time. I took a= break and went back into play the piano and sounded horrible! (like I hadn'= t tuned it at all) Here, the door being open during my 20 min break had equa= lized the humidity and temperature in the room and it had changed the tuning= . Lesson learned.              Yes= , it can happen. Jullia Gottchall, Reading, PA </HTML>