I added cork to the rear baffles ( Ikea placemats ) and reversed the super tweets to fire to the rear...reduces resonance and lessens the sizzle.

My gear rack from top to bottom: Bottlehead 2a3 Paramours, Bottlehead Foreplay III Preamp,Technics SL-1300 TT, Jolida JD9 Tube phono stage ( new ), Marantz SA8004 SACD player ( new ) and Dayton APA150 mono-blocks. RCA cables by Zu and Blue Jeans. Speaker cable by Walmart/Woods Patio Cord