This Recommendation describes the Modulated Noise Reference Unit (MNRU), a standalone unit for introducing controlled degradations to speech signals. The MNRU has been used extensively in subjective performance evaluations of digital processes as reference conditions. Historically MNRU was implemented in analogue hardware. The Recommendation was subsequently complemented with the description of digital implementations of the MNRU for narrowband and wideband signals. This revision provides the extension of digital MNRU to fullband signals, which shapes the flat gaussian noise used in the narrowband and wideband version with an average speech power spectrum. The introduction of the shaped noise provides a more representative degradation for super-wideband and fullband speech as it reduces the energy of the noise towards high frequencies. A reference implementation of the algorithms is provided in the Software Tool Library (STL), ITU-T Rec. G.191.