This is a bare board of tube differential line amplifier based on Borbely EB-894/211. Each board consists of one audio channel only. The amplifier uses one ECC83 as differential amplifier and two ECC81 as low impedance output stage. Being differential in structure, the board can be used as unbalanced/balanced input to unbalanced/balanced output amplifier application. We provide schematic and part list for this PCB. Each channel contains one audio channel. For stereo application, two channels are needed. The assembled board pictures are for reference. The listing is for ONE BARE PCB. Specifications: Frequency response : 10Hz - 120KHz Gain : 22dB THD at 1KHz 3V : 0.04% 10V :0.14% 20V:0.45% 30V:1.25% 40V: saturation Output impedance: approx. 100 ohm Supply voltage requirement : HT +260V to +300V 20mA ; -9V to -12V filament 12.6V 1A PCB dimension: 175mm x 74mm. PCB thickness 1.6mm. Thick copper ( 2oz, 75um !!) is used, Gold-plated surface, doubled-sided processed. We do air shipping worldwide at US$5.00. We welcome combine shipping. Track Page Views With Auctiva's FREE Counter Powered by SoldEazy