The first project was focused on recording a certain sound from a piano. His early technique was crude. He simply jammed the mike against the piano's frame. When we use a regular microphone we're actually counting on the vibrations in the ear to move some element in the microphone to generate voltage which we can then record. In his early works, Lerman attached piezoelectric devices directly to window screens, sheets of metal, and glass.
Scientists often use such devices to measure vibrations and tiny fluctuations in pressure.
Lerman found that every object had its own sonic flavor. Lerman also attached the devices to plants in their natural environment which led to his work in sonic mapping. For a performance piece in the late 1970s, he built piezoelectric transducers to amplify the spokes of bicycle wheels. He progressed to building specific preamplifiers for specific piezo disks, always looking for ways to achieve the best possible audio. Lerman would never claim to be an engineer.