Hertz St 25k Neo Tweeter Kit Reviews Hertz ST 25K NEO SPL Show | Compression 107dB Tweeter With Crossover Technical details: Size mm: 44 (1., 8). Hertz HT 25 Tweeter Car Audio System - Wajid Auto Frequency response Hz: 3k ÷ 20k., Sensitivity dB SPL: 107., Voice coil diameter mm: 25 (1) Magnet: neodymium., Cone/dome: aluminium. The Kit version, ST 25K Neo features metallic mesh grille and inline crossover filter included. Data table. Size mm (in.) 44 (1.8). Power Handling - Peak W... ST 25K NEO High performance compression driver The NEO series tweeters are a whole new project that is lighter and more compact compared to the previous ST 25 and offers superior performance thanks to the use of neodymium N38 H for the motor units and a FEM-optimised driver/horn design (finite element method). Voice Coil With Pry Tool Hertz VC-25-NEO Replacement Voice Coil Pair For ST 25 NEO Tweeters ST 25 NEO Tweeter Repair Part Component: High Efficiency Compression Driver , Weight: ., 86 lbs , Magnet: Neodymium , Cone: Aluminum , Impedance: 4 ohms