Cricket sound effects free download series#

The efficiency achieved with the proposed design is 100 The SPL obtained is comparable to the existing designs and ranges from 40 to 60 dB at 1 kHz at 1 cm with different sizes of the micro-speakers. We compare the conventional design of electrostatically actuated audio speakers - where typical electrode separation gaps are around 60 to 100 μm and actuation voltages are in the range of 10 to 200 volts - with the proposed peripheral electrode design with an electrode separation gap of 1 μm and actuation voltage ≤100 volts. Finite element analysis shows that under dynamic conditions, we can achieve diaphragm deflections as much as 80 times the gap between the electrodes because of the proposed design. The novel electrode configuration mitigates the squeeze film damping and increases pull-in voltage when compared with the conventional parallel plate electrostatic transducer design. We design and fabricate electrostatically actuated micro-speakers with circular diaphragms and peripheral electrode configuration. We found that body size and sound radiation efficiency were the main constraints at the lower limits, whereas the energetics of stridulation using the clockwork mechanism may pose a constraint at higher frequencies. We then explored the reasons for this apparent evolutionary constraint on field cricket carrier frequencies at both the lower and higher limit. Although the nine species spanned the evolutionarily conserved spectrum of carrier frequency and body size in field crickets, they were clustered in a small region of the available design space. We then used the model to explore the plausible evolutionary design space for field cricket call carrier frequency along the axes of resonator size and thickness, and mapped the locations of the nine experimentally measured species in this design space. The model allowed accurate predictions of carrier frequencies for all eight species to within a few hundred hertz from morphological measurements of their resonators. In this study, we explored the use of a finite element model (FEM) of the stridulatory apparatus of a field cricket, Gryllus bimaculatus, based on experimental measurements of resonator geometry and mechanical properties, to predict the measured call carrier frequencies of eight other field cricket species, ranging between 3 and 7 kHz. Based on the understanding of how this natural transducer works, one can design and fabricate efficient microscale acoustic devices such as microelectromechanical systems (MEMS) loudspeakers.įield crickets (Family Gryllidae, Subfamily Gryllinae) typically produce tonal calls with carrier frequencies in the range 3–8 kHz.

The characteristic song frequency produced is unaffected by variations in the spacing of file-teeth and even by larger gaps. Subsequently, we use our FE model to show that the natural design is quite robust to perturbations in the file. We show that the harp indeed produces beats and its frequency content matches closely that of the recorded song. We model impulsive loading based on a loading scheme reported in literature and predict the transient response of the harp. We fine tune the model with appropriate elastic boundary conditions to match the natural frequency of the harp of a particular species-Gryllus bimaculatus. With careful measurements of the harp geometry and experimental measurements of its mechanical properties (Young's modulus determined from nanoindentation tests), we construct a finite element (FE) model of the harp and carry out modal analysis to determine its natural frequency. The forced vibration response results in beats producing the characteristic sound of the cricket song.

The file-and-plectrum act as a frequency multiplier taking the low wing beat frequency as the input and converting it into an impulse - train of sufficiently high frequency close to the resonant frequency of the harp.

Cricket sound effects free download series#

This transducer uses two distinct components - a file of discrete teeth and a plectrum that engages intermittently to produce a series of impulses forming the loading, and an approximately triangular membrane, called the harp, that acts as a resonator and vibrates in response to the impulse-train loading. Here, we present an example of such a transducer that is used by field crickets to produce their characteristic song. At small length scales, there are many transducers in nature that we are now beginning to understand and learn from. The clever designs of natural transducers are a great source of inspiration for man-made systems.