Details:

Sound features: dynamic sharp / low frequency with elasticity / sound field width / three fields are balanced. Preamp board Works voltage: +DC280V (above 10ma ) X 2 groups and + DC12.6V ( above 0.8A) Power supply board input voltage: 0-AC220V X 2 (200V-240V are ok) 0-AC12V X 1 (12-15V are ok) Preamp Board PCB Size: 100 x150x1.6MM PSU Board PCB Size: 130x70x1.6MM Taiwan metal film resistance 1% accuracy MKP coupling capacitor Ceramic tube socket. This board can using 3pcs 12AX7 or some other same type tubes (12AXX series are all ok). if you want change using Filament voltage 6.3V tubes. such as 6N11/6N2.... can adjust the power supply board lower voltage to 6.3V. and the input Low AC voltage 6V-9V are ok.

Note：

Diy kit：all parts need buyer to solder，one preamp board kit + one PSU board kit Assembled board：have tested well， one preamp assembled board + one PSU assembled board

Bare Pcb：not included any parts ！ one preamp pcb + one PSU pcb Not included tubes and transformer !

Suitable transformer link:

recommend transformer : https://www.ebay.com/itm/353064388819 Tube link：https://www.ebay.com/itm/353491044405


Image 01 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 2 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 3 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 5 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 6 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 8 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 9 - HIFI Vacuum 12AX7B Tube Preamp Board Refer Marantz 7 Circuit +DC280V PSU Board

Image 1 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 2 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 3 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 4 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 5 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 7 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 8 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit
Image 81 - PRT-07A Tube HIFI Preamplifier Vacuum Tube Preamp Board Base On Marant 7 Circuit