Piano owners fall into two categories: those who tune regularly… and those who don’t.

If you’re in the second group, you’re in good company. I’ve been there myself. I play often, have a decent ear, and most days my piano sounds fine. Fine-ish. The notes are friendly with each other. No one’s fighting.

But here’s the catch: there are two kinds of “in tune.”

One of the coolest things about pianos is their range. If you exclude the pipe organ (and your cousin’s digital keyboard he’s been using to make dubstep since 2012), the piano has the largest range of any instrument — certainly any stringed one. That means one instrument has to produce both thunder-low bass and crystalline highs, and that creates a fun design problem.