My stereo isn't doing it for me. Need advice

Since music sounds good at lower volume and louder sounds worse, I think it's your room.
Room treatments and setup may help.

Some people including myself (previous room) have had success setting the system up diagonally. IOW the rack between the speakers is in a corner, and behind you is the opposite corner.
Steve Deckert has a paper on it. I had similar issues, read the paper, set up diagonally and kept it that way until I moved into another room.

http://www.decware.com/paper14.htm

Been moving my speakers around. LP's sound pretty good. Just hooked up an Oracle Alexandria turntable. I do think my cd player is the weak link. I also have some framed concert posters on the side wall and behind me. Those must stay. I have the sub turned down pretty low.
The Dynaudio x12's sound better than the x32's in the room. I just wanted a fuller sound. Sound is thin to me.

Change your preamp tubes to Tungsram or RFT from Tubestore in Hamilton, Ontario.

You have to have a reference for what sounds good to you before you can attempt to replicate it.

Have you heard a system or systems that sounds really good? What were they? What did it sound like? That would be your reference. Could be at a show, dealer or another person's home.

You can't hit the bullseye until you know where the target is.

other than that, on paper, the Class D amps are probably a better match to the Dynaudio speakers. I do not know of any Dynaudios that are tube amp friendly.

Other speakers would likely do better with teh PL tube amp.

I'd get a good amp/speeaker pairing in place with speakers that best fit your likes and your room specifically and then tweak from there.

So there are various ways you can practically tackle the problem but its hard to say what the best way is until the target sound you are shooting for can be better described.

BTW I own Dynaudios and run them off a very good quality BEl Canto Class D amp and this is a very good match to work with.

I have also heard KEF ls50s in my system. Like Dynaudios, these are also not tube amp friendly speakers. THey sounded good with my 500 w/ch Class D amps also in a smaller room but very thin off a different 180 w/ch SS amp (not Class D) in a larger room. These are good speakers but small so they can only provide full sound in a room that is not too big.

So all your speakers are a match on paper to teh Class D amp, and are not tube amp friendly. SO best PERFORMANCE with Dynaudios and teh KEFs will be achieved with a high power Class D or similar SS amp.

Applying a sub to offload the low end would work towards the end of using these speakers with the tube amp.

You have the best chance of getting the best sound fastest by optimizing the performance of teh gear that will be working together. Once performance is optimized, ie all gear is a technical match, tehn you are in a position to tweak teh sound to your tastes in various ways from there.

BTW I have heard of several cases where people were sold Primaluna tube gear by dealers with no consideration to what speakers would be used. In all cases the tube amp was changed to a more suitable SS or Class D amp specifically to get to where people wanted.

Or you could go with higher efficiency easier to drive speakers like Tekton or ZU or Klipsch for example to match to the tube amp better.

If tyou keep the PL tube pre-amp, make sure the input impedance of the Class D or SS amp you use with it is 40Kohm or higher in order to assure a good match between higher output impedance tube pre-amp and SS amplifier. IMpedance matching like this is another key for optimizing performance as a stepping stone to getting the best sound possible via tweaking from there.