Banner Image

Committed Classic Tube and Open Baffle Speaker Linkwitz -Lx521.4 Fan - Over the TOP Thrilled with ZA3 !

Committed Classic Tube and Open Baffle Speaker Linkwitz -Lx521.4 Fan - Over the TOP Thrilled with ZA3 !

I was a convert and experimenter with Open Baffle Dipole Magic for 10 years until settling on the Linkwitz LX521.4 design with directly driven drivers all crossover functions handled by DSP. Although I did modify from Mr. Linkwitz's final design by using ribbon tweeters and single subwoofer the core of the speakers remain Linkwitz design. I also have been using Tube Amplifiers as my driving source and tried Class D 8 years ago. I tried it one time and never hooked it up again shocked at how bad it sounded! The LX521 are extremely revealing and full dipoles from 20 to 20,000 cycles using 4 drivers each. Recently I saw the reviews of the Fosi ZA3 and being super happy with the sound purchased three more units providing the 8 amplifiers for all 8 directly driven speakers. Happy as a Clam I am! Mr. Linkwitz actually preferred Class D as his amplifiers but the price was beyond my budget at the time. I built my own switch box to change between my Tube Amplifiers and the ZA3's. I am adding the Sparkos ss3602 in the near future to add a bit of refinement to the sound on the upper end. Super Happy with the result ! The Tube Amps VS the Class D ZA3 do sound different as the ZA3 is more up front, punchy and direct. I still love my tube amps but have added a whole new sound scape to my system. Using my switch box easy to choose either as my mood tells me. A big thumbs up on the ZA3!

As Mr. Linkwitz said "if its good enough for you its good enough"! I don't hesitate to encourage Tube Fans to give these a try!


  • IMG_20240424_203759.jpg
    562.5 KB · Views: 1
  • IMG_20240429_054614.jpg
    339.8 KB · Views: 1
  • IMG_20240429_055100.jpg
    439.2 KB · Views: 1
  • IMG_20240429_055113.jpg
    402.4 KB · Views: 0
  • IMG_20240429_055214.jpg
    818.9 KB · Views: 0