This paper deals with the adaptation to wideband of the MBE coder which was initially developed for the telephone band. As the constraints of quality and bit rate for a wideband and a telephone band coder are different, and as the signal characteristics on these two bands are different too, we must reconsider the coder structure. Several improvements are proposed, some of which were already proposed for the telephone band such as the phonetic classification of the frames or the multi-harmonic modelling of the spectrum. We also propose in order to reach a good quality, especially for high frequency voices, to model and synthesize, as part of the signal, the initial error between the synthetic and original spectra.