Patent ID: 7894613

Claim:
A computer server room with a controlled cooling fan noise, comprising: one or more system racks, wherein the one or more system racks have a plurality of systems and a plurality of cooling fans to cool the plurality of systems, the cooling fans emit fan noise while running; and one or more transducers coupled to one or more walls of the one or more system racks, the coupling configured to enable the one or more walls to function as diaphragms for the one or more transducers; at least one microphone installed near a location where fan noise needs to be controlled; and one or more active noise control units, wherein the at least one microphone collects fan noise signals and then sends the collected signals to the one or more active noise control units, the one or more active noise control units send control signals to at least one of the one or more transducers to emit transducer acoustic waves to reduce or to eliminate the fan noise; wherein the one or more active noise control units send control signals to the at least one transducer to emit transducer acoustic waves at about 180 degrees out of phase with the fan noise and at an intensity and a frequency substantially equal to the fan noise; wherein each of the one or more transducers comprises a fan identification and speed detector that determines which fan is running and at what speed, a room sound detector to detect the sound signals received by the microphone, and a transducer controller to issue control signals to the one or more transducers; wherein the transducer controller comprises a component location sensor, a transducer location identifier, an intensity setting unit, and a phase and frequency setting unit, wherein the component location sensor communicates the locations and status of components on the system racks to the transducer location identifier, the transducer location identifier selects which transducers need to be activated based on the locations and status of components and communicates which transducers have been selected to the intensity setting unit and the phase and frequency setting unit, the intensity setting unit, and the phase and frequency setting unit receive fan noise signals from the microphone and which transducers have been selected from the transducer location identifier, send controlling signals to the selected transducers to emit acoustic waves to reduce or to eliminate fan noise.