It depends up on your listening tastes. If you want warm mellowing sound you can go for good bookshelf speaker on stand Dali mentor 2 or ATC or B&W 685 or 805. If want a good mid range clarity speaker you can go for spendor Or Ls3/5a built up speakers. If you want good speaker punchy speaker you can go for Monitor audio gold or above or Jm lab or Klipsch. Some may since Klipsch is more sensitive it will not match with Krell. With matching speaker wire you can get good dynamic sound from Klipsch. My FPB 200 is very excellent in fine hf to good mid frequency. When it comes to bass it needs a high sens speakers or towers. In one of my friends house I heard through a vintage Jbl 10 inch woofer system the bass was amazing totally great, Thanks. I found My Accuphase e 303x and Krell Fpb 200 are totally different in quality.