Thanks so much for your reply. Did you try D90 as DAC with your Singxer SA-1? How was the pairing?I dunno.. I'm powering HE-6 with the Singxer SA-1 on high gain and it's got plenty of juice left. Dac pairing is important to me so I have a more forgiving Gungnir A1. Everything sounds fantastic. My system was harsher before with D90/A90. Now, no fatigue.