The exterior of these four new products features thick aluminum and a seamless assembly.  The 550A features 60 Watts into 8 Ohms while the 650A features 75 Watts into 8 Ohms.  They both have enhanced output stages, transformers, input circuits and include six inputs and two outputs for connectivity.  The CD players have integrated a Cambridge Audio S3 servo solution along with Wolfson WM8740 DACs, and several audiophile-grade components.