$8k for speakers - new or used

I still have a pair of the original 804's purchased back at the end of 2002.  They still sound quite good, and they are now a part of my Son's system.  Like all 3-way loudspeakers, they require optimal placement.

With the refinements in the D4 model, they should be fantastic.  In my setup, I never required much toe-in.  You may have to experiment with moving them away from the back and side walls.

I have moved on to a smaller home and a 2-way stand mount loudspeaker from Wilson Benesch.  They are matched the W-B Torus system.  Don't give up on the 804 D4's.

I might suggest a different tube preamplifier.  Have a look at the Quicksilver Audio Line Stage offering: https://quicksilveraudio.com/products/line-stage-preamp/

Happy listening

Just wanting more - maybe detail, punch, bass.

Get the Mofi Sourcepoint 888...

Erin’s Audio Corner - Mofi 888 Review

When you realize what the tonally imbalanced, mid starved, fake detail B&W robbed from you all these years, sell it to a member of some B&W admirers club and get some money back.

@goducks44

believe it or not your speakers will be hard to beat in your budget.

maybe add subwoofers like RELT9x which pair nicely.

your b&ws sound better than most speakers under 10k.  something new will sound different but not better.  try aiming your speakers straight out from the wall, about 3 feet from the wall and wider apart than the distance from your chair. 

Adding subs, one or two?  What about placement. REL or JL Audio?

Definitely two.  I have successfully put subs between main speakers and rack, minimum 12 inches from back wall.  

Of the (4) different sub brands I have owned JL Audio has the most punch with the deepest notes, the E110 or 12 are great.   

REL adds punch alongside your speakers but lacks the deepest notes.  
SVS is the best value, the SB3000 is excellent of you have the room.