I understand that the 48dB of attenuation I mentioned is theoretical, and that in practice it may be significantly lower, perhaps as low as the 12dB you mention. A few things...

-12dB is more than enough attenuation for my needs.

-Several state of the art DAC manufacturers use digital attenuation, including Weiss, Berkeley, and Wadia.

-I am perfectly happy with the SQ I am getting with my Sonos + Empirical Audio reclocker + G68.

-This whole discussion is irrelevant to the topic of this thread, which is...

G68 volume: How does it work?

iMac -> Sonos -> Empirical Audio reclocker -> G68 (modded) -> Pass Labs XA30.5 amp -> Focal 1027be speakers + JL Audio F113 sub. Pioneer Elite PRO 151FD 60" display.

G68 mods... Custom power supply, Audiocom Superclock 4, Rubycon capacitors, WBT Nextgen connectors, ultra low noise op amps, analog output buffer, DSPC c00044, Revelation One filter.