The pre-amp's line stage is important and its presence is audible and influential on the signal it receives either from a phono stage (or an outboard phono stage) CDP, what ever. If your phono stage has tubes and your line stage has tubes then you have 2 opportunities to dial in the tone you want. Some times just the tube in the phono stage will do it, some times just the line stage, more often than not both. Operating on the assumption (I do not know about the PV12) I would start by selecting a tube for the line stage that has a general reputation for being neutral in tone, quiet, and rugged. Then I would try to find a tube that produced the tone you want from the cartridge you are using. It is not always easy to get this right so take your time.
A good place to start is to tell folks what kind of cartridge you are using now, what kind of tone you are getting, and what you would like to improve. Also indicate what tube you are using in the line stage and what tone it is producing as it relates to any source you use. With that info I'm sure there are some folks who can give you some specific and knowledgeable advise.
A good place to start is to tell folks what kind of cartridge you are using now, what kind of tone you are getting, and what you would like to improve. Also indicate what tube you are using in the line stage and what tone it is producing as it relates to any source you use. With that info I'm sure there are some folks who can give you some specific and knowledgeable advise.