In order to reduce the transmission bandwidth requirement for the spectral envelope parameters for Multiband Excitation (MBE) coders [1] Linear Prediction (LP) modelling has been widely investigated [2, 3, 4]. In this paper we compare the direct methods for evaluating the linear prediction filter [2, 3] with a novel iterative LP modelling technique. A novel switched Vector Quantizer (VQ) is employed to transmit 12 binary V/UV harmonic decisions [5] using only 4 bits which achieves only 5% errors. To enhance robustness joint source and channel coding codebook design and search has been incorporated into the coder.