If you don't know about the do's and don'ts of using tubes with solid state, we can make it simple for you: You can include a tube component into virtually any system, into any position, with no limitations.   There is only one area that you need to keep in mind.  Running a tube preamp into the small handful of the solid state or tube amplifiers that have an input impedance that falls outside the norm.  We're talking about maybe 1% of the amps out there. 

Don't get stressed.  This is easy stuff.  All you have to do is look at the owner's manual or spec sheet on your amp and you will see something that says "Input impedance".    

If you are adding a tube preamp and hooking it up to an amplifier, the input impedance of the amp should, in general terms, be ten times (or more) the output impedance of the preamp. If it isn’t 10X, or maybe it’s close, you may still get incredible performance.

The DiaLogue Premium Preamplifier has an output impedance of 256 ohms, so it will mate with virtually any amplifier on the market we are aware of.  The ProLogue Premium Preamplifier has an output impedance of 2800 ohms. It will be compatible with 99% of the amplifiers we know of, but there are a few amps that fall out of the norm.  For the ProLogue Premium, it would be best to use amplifiers with an input impedance of 28K ohms or higher. However, we do have several reports of customers using amps with an input impedance of 25k ohms and having great results.

Most tube amplifiers have an input impedance of at least 100K Ohms, so they are compatible with most any tube preamp. Most solid state amps have an input impedance of 50K ohms, so the output impedance of the preamp should be 5,000 ohms or less. A few amps that have been made over the years that have an input impedance that is lower than normal. There are a couple models of Pass Labs amplifiers, specifically the older Aleph models. You should refer to the owner’s manual for the amplifier you own.

There it is. The mystery solved. All you need to do is remember the 10X rule. Input impedance of the amp should be roughly 10X higher than the output impedance of the preamp.