4 or 6 outlet conditoner for amps/sources

I am looking for a conditoner that does a conditioning job without limiting dynamics. I am looking to plug a tube CD player, a tube preamp, and a pair of monoblocks into it. Can any of you make some suggestions on a recommened product or your experiences with different products/literature? Should I be looking at one box for conditioning or separates for source and separate for amps. Ideally, price should be under 600 USD on used market and offer surge/spike protection as well. THanks for all your input. Dave