Thank you Gagey for your reply. The original sentence is from "The King's Speech" screenplay. Here is the passage :"The reader speakes in flawless pear-shaped tones. There's no higher creature in the vocal world."
On an oscilloscope or oscillograph, the "pear shaped tone" looks exactly (more or less) pear shaped - in a display of amplitude versus frequency. Regularly spaced harmonics vary smoothly in amplitude, with most of the content in the lower harmonics, tapering smoothly to lower amplitudes. The "ideal" tone contains "rich" harmonics though the upper second octave - the body of the "pear." Into about the third octave, there are "rich" harmonics, but with lesser amplitude - the neck of the "pear," with little content above about the third or possibly into the lower fourth octave.