Great info thanks! I had a DAC with the Sabre 32 it had a hardness in SQ - but very detailed. The Eastern Elec MiniMax Plus - choice of rollable opamps (socketed) and tube outputs. No matter what I tried I could not get it tonally where I wanted and sold it. http://www.enjoythemusic.com/magazine/equipment/1212/eastern_electric_minimax_dac_plus.htm MSB Tech - the R2R giants published this on the D-S 32 bit DACs - http://www.msbtech.com/support/What_about_32_bit_DACs.php?Page=supportHome And the issue of chip on board opamps high lighted here: http://funwithaudio.blogspot.com/2012/01/today-in-electronics-everything-is-made.html Alex at APL found a way to hotwire the AKM 32-bit D-S multi-segment chips and run them in series . The reason I choose the classic 24-bit R2R PCM1704UK based DAC60 to begin my mod project - the results far exceeding my expectations: http://www.head-fi.org/t/740362/lite-dac60-pcm1704-r2r-tubed-dac-mod-project I'm in awe of the Yggy! That is very cool technology - and the SQ is excellent I hear. 'm a tubed DAC guy so these would be on my 'lottery money' list: APL DSD-M: http://www.aplhifi.com/products/dsd-m Total DAC D1 Tubed: http://www.totaldac.com/D1-tube-eng.htm Aqua La Scala MK2: http://www.aquahifi.com/la_scala.html Cheers!