Modulations present in vibration signals generated by rotating machinery might carry a lot of useful information about its technical condition. The paper describes a technique for detection of modulations in vibroacoustic signals, called modulation intensity distribution (MID), which, as proven might be considered as a generalized description of the spectral correlation density. Additionally, the paper includes the description of integrated MID (IMID) which allows to present the results of MID in a simplified form. As a conclusion, the discussion is held on the application of IMID to industrial condition monitoring systems.