The invention relates to a device to be used in processing of a surface of metal object to be processed which surface is essentially continuously in onwards motion. In doing so, a characteristic value for knock is detected in at least one cylinder of the internal combustion engine in inhomogeneous stratified operation. A variety of sensors may be selectively placed into communication with a sample chamber within the cell body to evaluate the sample at potentially high pressures and temperatures. A zone is disposed on the second spline member and has a first profile. The second switches are controlled to couple a signal associated with the particular piezo ceramic element of the at least twenty five thousand piezo ceramic elements to an input port of the processor.