Maintained. ALTEC's crossover variable frequency network. You can switch between 500/800/1200, and you'll want to drive your best with a variety of drivers. The graininess and sound cuts are also a good impression (Oikawa Tetsuji)
Maintenance information: 2026.4.26 maintained (ATT VR winding part defective implantation replacement, contact partial dismantling)
Main specifications: Crossover 500 Hz, 800 Hz, 1200 Hz switched with a jumper, banana plug input compatible W191 x H110 x D350 1.8 kg/bottle