Pairing tube pre with SS amp

I plan to purchase an Audio Experience Symphonies tube preamp in the next few months. It will be coupled with an ATI 1504. What do I need to consider with regard to compatibility? I have heard something about frequency and what not else. Please define terms if too difficult. If it helps, I am using a Cambridge Audio 500 SE CD player and Pinnacle Aerogels.

And while you are at it, please don't hesitate to give any suggestions for a pre in the $350-$450 price range, even used.

All my thanks.
Here's a thread discussing a very similar question.

I sound like a parrot, but a used Counterpoint SA-2000 is in your price range. While you surely could find something less risky in the reliability department, the SA-2000s are very nice sounding. Plus they have a SS output buffer, so matching them to SS amps is not an issue. Good luck

Take a look at MapletreeAudio preamps. The Ultra 4 I think is within your price range. Very good preamps, worth 3x the price. Bettered my and my brother's preamp costing, $1000-1500. Dr. Lloyd is a wonderful and knowledgeable guy. Its a shame that only few people know about his product. Maple Tree Audio Design is in Audiocircle forum. Good luck.