One of the Command Performance AV rooms at Capital AudioFest featured Carnegie speakers, the CST-2 ($5999/pair), which combines a Mylar-film planar tweeter with eight 5.25" composite-cone woofers in a slim tower supported on a marble base. The speakers were driven by Manley Mahi EL84 monoblocks and a Manley 300B preamp, with the source a silent CommandPC server feeding 352.8kHz USB data to the Light Harmonic Da Vinci DAC that had impressed at the Atlanta Axpona. The DAC has been upgraded since Axpona: when handling 16-bit data, it would pad out bits 1724 with 0s to give 24-bit data, which is standard practice. But in 2s-complement digital arithmetic, which is how audio data are encoded on a CD, there are actually two zero levels: 16 0s but also 16 1s, which represents a magnitude one LSB lower. Light Harmonic's engineers found that if they padded 16-bit data with 8 1s rather than 8 0s, the sound improved.