The input impedance of the Pass can be challenging for many tube preamps, including the ARC, which was covered in another thread.
This usually has to do with the output coupling capacitor of the preamp. A few tube preamps (a very few) are direct-coupled and so don't have this issue. At least one not only has direct-coupled outputs but is also fully differential and balanced. So it is possible to have the smoothness and detail of tubes without giving up anything in the bass.
This usually has to do with the output coupling capacitor of the preamp. A few tube preamps (a very few) are direct-coupled and so don't have this issue. At least one not only has direct-coupled outputs but is also fully differential and balanced. So it is possible to have the smoothness and detail of tubes without giving up anything in the bass.