Gena, the following discussion which I've linked previously is possibly the most complete examination of possible clipping damage which is available online. Both the compression and harmonics theories are examined along with brief mention of other possibilities. As you'll note, it reaches no definite conclusion. This is part of the material which Dr. Lesurf originally prepared for introductory use by his students in electronics and physics at St. Andrews.

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Enjoy the music, not the equipment.