What preamp do you have? I have switched back and forth on several preamps from solid state to tube rectifier, but each of them was a DIY unit where I had intended to have this flexibility when I built it. A commercial preamp with solid state rectifiers may not be as easy to modify. For example, you need a power supply for the heaters of the tube rectifier. An all solid state preamp is not likely to have this capability. A tube preamp will already have a 6v or 12v supply which might be able to supply the voltage needed for a tube rectifier, but it may not have the current capability to handle a rectifier tube as well as the signal tubes. If the preamp has a 6v supply and has enough current capability, you could theoretically use a 6v indirectly heated rectifier tube such as a 6X4, but the resulting B+ voltage will be lower than with a solid state rectifier. That may or may not be a problem.
Of course, if you have the skills to build an outboard power supply for your preamp, you can basically build anything you want. You can use a different power transformer that has a slightly higher voltage output to account for the losses with a tube rectifier, and the new transformer can have the proper voltages for the rectifier tube as well as signal tubes.
Of course, if you have the skills to build an outboard power supply for your preamp, you can basically build anything you want. You can use a different power transformer that has a slightly higher voltage output to account for the losses with a tube rectifier, and the new transformer can have the proper voltages for the rectifier tube as well as signal tubes.