yeah i know about the calyx. the calyx 24/192 dac also has the same 2.2V/6.8V output. i didnt know it was due to the es9018 chip because like you said many other es9018 chips have lower output levels. still it's a bit werid that the rca output is not half of xlr output. i guess they go through completely separate analog output stages/circuits?
and yeah as for x-sabre on powered speakers i'll just wait and see myself i guess. thanks for the help guys
It has to do with the way they sum the 4 DACs per channel in the ES9018 when using single ended mode. But the 6.8V output is kind of like a headphone amp centered around the TPA6120 driver chip - the specs call for 10 ohm output impedance, so that's what you'll see more often than not. But some companies (Audinst for example) use alternative methods to get the output impedance lower, which they feel is worth the trouble.