This is from the manual:@orrman
Which tubes does the unit come with stock? I’m guessing these are configured as right/left channel input/driver on one side and output opposite? Looks very cool! I’m working with an Atlantic TRP3 that I’ve had for just over 6 months now. The Poseidon was announced a couple of months after I received my dac. I haven’t heard one yet but there are many out there making the upgrade. Out of curiosity- how is the volume control working out with your Riviera?

You can run it single ended with half the tubes if you desire. I think I might do that later on, will make rolling easier.
I run Levante on 12 o'clock on its pot and then control volume with Poseidon. Out of 63 steps on its volume control my comfortable listening is between steps 28 and 42 so that's seems like a good balance between the two components.
With Poseidon on volume control bypass with my sensitive 96db speakers I barely have any room on the Riviera pot