The tubes are available?

Could anybody help me to confirm this: I have an old (but good sounding) Wadia 15 DAC with only BNC coaxial and AES port, and support at maximum 48khz sampling rate. Can it run smoothly with DI-20? And can I disable the DSD upsampling function of the DI-20? Thank you!

Please help with a question of a newbie here. Before I used a Teradak's Raspberry Pi to connect directly to my old Wadia 15 DAC via coaxial cable (my DAC does not have USB port). Now I want to connect my Pi to Gustard U16 (via USB) and feed to my DAC via coaxial cable. My question is: - I want...