A scanning acoustic microscope (SAM) - a nanomicrophone using a piezoelectric crystal, may be used to examine bacterial colonies, not just materials specimens to detect phonons and listen to propagating microfractures.

Since bacterial cell walls are rigid structures, they undergo mechanical distortions when channels open and dose. This causes them to squeak and pop, each channel having its own sound. Channels and receptor molecules are all of different sizes and shapes, and therefore deform the cell wall in unique ways. This means that each channel makes a unique (if faint) sound when it passes a molecule through itself and this activity can be delected, Transport rates of uptake and excretion for the various compounds car then be calculated trom the intensity of the sounds.