This initial use of piezoelectricity in sonar created intense international developmental interest in piezoelectric devices. The breakout of World War I marked the introduction of the first practical application for piezoelectric devices, which was the sonar device. Over the next few decades, piezoelectricity remained in the laboratory, something to be experimented on as more work was undertaken to explore the great potential of the piezoelectric effect. Their initial demonstration showed that quartz and Rochelle salt exhibited the most piezoelectricity ability at the time. By combining their knowledge of pyroelectricity with their understanding of crystal structures and behavior, the Curie brothers demonstrated the first piezoelectric effect by using crystals of tourmaline, quartz, topaz, cane sugar, and Rochelle salt. The direct piezoelectric effect was first seen in 1880, and was initiated by the brothers Pierre and Jacques Curie. The piezoelectric effect also has its use in more mundane applications as well, such as acting as the ignition source for cigarette lighters. It is also the basis of a number of scientific instrumental techniques with atomic resolution, such as scanning probe microscopes (STM, AFM, etc). The piezoelectric effect is very useful within many applications that involve the production and detection of sound, generation of high voltages, electronic frequency generation, microbalances, and ultra fine focusing of optical assemblies. When reversed, an outer electrical field either stretches or compresses the piezoelectric material. When piezoelectric material is placed under mechanical stress, a shifting of the positive and negative charge centers in the material takes place, which then results in an external electrical field. One of the unique characteristics of the piezoelectric effect is that it is reversible, meaning that materials exhibiting the direct piezoelectric effect (the generation of electricity when stress is applied) also exhibit the converse piezoelectric effect (the generation of stress when an electric field is applied). The word Piezoelectric is derived from the Greek piezein, which means to squeeze or press, and piezo, which is Greek for “push”. Why Fishman made such a beast is beyond me.Piezoelectric Effect is the ability of certain materials to generate an electric charge in response to applied mechanical stress. Attenuation is a must here, no amp out there can take the signal without clipping. The high output Z is very hard to attenuate without affecting the sound. I have tried using resistive voltage divider attenuation to do this feeding into a common OA1 scenario but I have not been happy with the results. While I am now testing this inverting attenuation circuit on its own, in the end it is intended to be the piezo only input of a complete active guitar preamp as shown below where the other circuits are working as intended. Question: Before I go down a bunch of rabbit holes, is there an obvious practical issue with the design of my circuit causing this, or anything that sticks out that I should investigate? The first thing I checked was the integrity of my connections but all looks good. While I have not actually measured the FR yet, the real world result is about -15db overall and cutting out LF to have a tinny sound. In Circuit Lab the simulation is exactly how I would like it. The circuit models both the pickup output impedance and load of the cable capacitance with amplifier input impedance. The circuit below is meant to attenuate a high output and high output impedance piezo electric guitar bridge pickup -7 dbV.
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