HV-1 Headphone Amplifier Finished Board With ALPS 27 Potentiometer- Reference Beyerdynamic A1 _x000D_ _x000D_ Descripcin del producto _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ The HV-1 of the HV-X series is based on the AMP circuit of the Beyerdynamic A1 headphone amplifier. After two years of perfection, it summarizes the experience of the fans in the actual installation and grinding machine._x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ HV-1 highlights:_x000D_ _x000D_ _x000D_ _x000D_ 1, the flow and tube, improve the driving force and control, the sound field is wider; effectively solve the original A1 circuit to promote AKG, Senhai series headphones, the medium frequency is weak, the control is poor, the effect is very obvious!_x000D_ _x000D_ _x000D_ _x000D_ 2, 300MV earphone special protection circuit, the current various types of A1 use UPC1237 chip power amplifier with protection circuit to act as a headphone protection circuit, 1.2V protection, boxes and headphones? You know!_x000D_ _x000D_ _x000D_ _x000D_ 3, Omron power relay, has a larger contact and copper than a small signal relay, the signal loss is lower._x000D_ _x000D_ _x000D_ _x000D_ 4. Separate power supply for the op amp in the AMP to improve the resolution_x000D_ _x000D_ _x000D_ _x000D_ 5, optimized ground processing, higher signal to noise ratio_x000D_ _x000D_ _x000D_ _x000D_ HV-1 hearing summary_x000D_ _x000D_ _x000D_ _x000D_ Three-stage balance, neutral alcohol and, adapt to all types of headphones, "Wild King" headphone amplifier_x000D_ _x000D_ _x000D_ _x000D_ Introduction to HV-1 materials_x000D_ _x000D_ _x000D_ _x000D_ High quality double-sided PCB with FR1.6MM sheet, 1OZ copper, pad spray tin_x000D_ _x000D_ _x000D_ _x000D_ Taiwanese 1% precision five-color ring resistor_x000D_ _x000D_ _x000D_ _x000D_ Main filter electrolytic capacitor: updated to FK series 3300UF 4 PCS,_x000D_ _x000D_ _x000D_ _x000D_ Evacuation capacitor for decoupling: warm sound system low resistance - Panasonic NXL audio master_x000D_ _x000D_ _x000D_ _x000D_ Italian AV electrodeless capacitor, sound and clean_x000D_ _x000D_ _x000D_ _x000D_ A1 Royal ST 33078N dual op amp, ST DB139-140 power output tube_x000D_ _x000D_ _x000D_ _x000D_ Constant Current Bias Circuit F BC550C-560C_x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ RIFA 840 4U7 super large volume coupling with MKP capacitors, spike ELNA Nikko, WIMA MKS series and other coupling capacitors._x000D_ _x000D_ _x000D_ _x000D_ High quality YS215A headphone jack (to cross the silver)_x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ NOTE: This is a finished board, welded debugging OK. _x000D_ _x000D_ _x000D_ _x000D_ PCB Size: 160mm*110mm _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ Works Voltage: Dual AC 12 - 16V _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_