A collar unit device comprising: a receiving cavity ; a metal electrode probe , wherein at least one elastomeric ring encircles the metal electrode probe , wherein the metal electrode probe comprises a first end and a second end; the receiving cavity for receiving the metal electrode probe , the receiving of the metal electrode probe comprising securing the metal electrode probe to the collar unit device , wherein the at least one elastomeric ring mechanically isolates the metal electrode probe from the receiving cavity ; a piezoelectric element , wherein the metal electrode probe is for detecting vibrations of at least one acoustic event and transferring vibrations of the at least one acoustic event to the piezoelectric element ; the piezoelectric element for receiving the vibrations of the least one acoustic event, the receiving of the vibrations including generating an electrical signal proportional to the frequency and magnitude of the vibrations; a retainer component for securing the piezoelectric element in a secured position, wherein the secured position comprises a surface of the piezoelectric element maintaining contact with the first end of the metal electrode probe , wherein the retainer component comprises a retainer and a spacer ; and at least one processor for receiving and processing the electrical signal, said collar unit device being characterized in that the retainer component comprises an inwardly projecting retainer rim and a plurality of outwardly projecting retaining components, wherein the outwardly projecting retaining components comprise retainer openings for receiving retainer screws . a receiving cavity ; a metal electrode probe , wherein at least one elastomeric ring encircles the metal electrode probe , wherein the metal electrode probe comprises a first end and a second end; the receiving cavity for receiving the metal electrode probe , the receiving of the metal electrode probe comprising securing the metal electrode probe to the collar unit device , wherein the at least one elastomeric ring mechanically isolates the metal electrode probe from the receiving cavity ; a piezoelectric element , wherein the metal electrode probe is for detecting vibrations of at least one acoustic event and transferring vibrations of the at least one acoustic event to the piezoelectric element ; the piezoelectric element for receiving the vibrations of the least one acoustic event, the receiving of the vibrations including generating an electrical signal proportional to the frequency and magnitude of the vibrations; a retainer component for securing the piezoelectric element in a secured position, wherein the secured position comprises a surface of the piezoelectric element maintaining contact with the first end of the metal electrode probe , wherein the retainer component comprises a retainer and a spacer ; and at least one processor for receiving and processing the electrical signal, said collar unit device being characterized in that the retainer component comprises an inwardly projecting retainer rim and a plurality of outwardly projecting retaining components, wherein the outwardly projecting retaining components comprise retainer openings for receiving retainer screws . <EOS>