RESONANCES IN AUDIO THEY'RE BAD THINGS - AREN'T THEY?
G BANK · 2023
Almost every musical instrument uses resonance to generate or amplify the sound output.Imagine listening to a violin with no body.So, it seems, some resonances are necessary whilst others are taboo.Maybe we should think of them as either good or bad resonances.It was Rice and Kellogg who published a paper entitled "Notes on the Development of a New Type of Hornless Loud Speaker" in 1925, with a description of an instrument of the piston type they had recently developed.It consisted of a lightweight conical diaphragm driven by a moving coil and they deduced that it would generate a flat pressure as well as a flat power response, at least up to the point where the diaphragm started to beam.Engineers like simple ideas and the concept of the "rigid piston" seemed the ideal solution for a loudspeaker -and we've been stuck with it ever since.Keeping the piston rigid also meant that we would avoid any resonances in-band, since these were regarded as bad resonances.This paper looks at the difference between good resonances and bad ones.The journey starts at Celestion, where the first scanning laser interferometer in the loudspeaker industry was designed and built.