lewm - Pretty much you have it correct. The Sugarcube only accepts analog inputs, so I use the tape loop output on the C220 to feed the equalizer. I have a choice of three headphone jacks - the C220, the Sugarcube, and the Marantz CD recorder. So far, I prefer the sound of the Sugarcube’s headphone stage over the other two.
When my amplifier is back, I will feed the tape loop input on the C220 from the Sugarcube, so listening to vinyl will be done through the C220’s tape loop.
Once the Sugarcube is fully functional for recording, including the track-splitting and meta-data functions, I will rearrange the outputs of the equalizer, via Y cables, to feed both the Marantz CD recorder and the Sugarcube, so that the Marantz will not be in the signal path of the Sugarcube inputs.
Separately, I successfully downloaded the Android app for the Sugarcube last night, connected the Sugarcube to my home wifi network, and calibrated the Sugarcube using the test record. It seems that the only function of the calibration is to set the input level on the Sugarcube for optimal recording levels. I also noticed that the Sugarcube received a software update, all on its own. I have not yet determine what was updated.