Vibration Based Condition Monitoring (VCM) is a well known maintenance technique in plants and industry. The technique requires a number of transducers at each bearing pedestal (two accelerometers, two proximity probes in addition to a tacho sensor) in order to detect any fault(s) in a machine, particularly for a large rotating machine. The high number of transducers leads to a huge amount of vibration data that need to be analysed to identify the fault(s). Hence such situation warrants a need of an improved diagnosis method with a reduced number of vibration transducers. Recently a method has been developed that uses just a vibration transducer on each bearing and data fusion to construct a single composite spectrum and bispectrum representing the vibration behaviour of the complete machine. This approach reduces the analysis of a number of spectra to just one composite spectrum and bispectrum for a machine which observed to be useful and simplified diagnosis tool for the fault(s) identification. The concept the composite bispectrum has now been extended to a number of simulated faults in an experimental rig at different rotating speeds.