A media bed support grid for use with a vessel having an inner surface. A server encrypts data using a master key and a symmetric encryption algorithm. When used in conjunction with a mechanically leveraged actuator structure the smart material actuator can be used to its greatest potential. Moreover, in one embodiment of the invention, a novel phantom-powered JFET preamplifier gain circuit can minimize undesirable sound distortions and reduce the cost of producing a conventional preamplifier gain circuit.