. We have demonstrated multiplexed readout of the full 000 pixel array with 000 of the pixels (00%) giving spectroscopic data. This is the largest multiplexed array of TES microcalorimeters to date. This paper will review the spectrometer, highlighting the instrument design, detector fabrication, readout, operation of the instrument, and data processing. Further, we describe the characterization and performance of the newest 000 pixel array.