ITEM NAME:6J1 Valve Pre-amp Tube Board Headphone Amplifier+Acrylic Case Kits Component DIY Description&Preview.Fever 6J1 tube preamp amplifier amplifier amp preamp bile buffer effect diy kit. 6J1 fever bile pre-level board is a circuit design principle of imitation machine music fax X-10D. It is rationally optimized, more stable than the original machine performance, and the electronic tube has been improved by 10%.
