Review on 🎛️ TOPINCN 6J1 Vacuum Electron Tube Valve Preamp Amplifier Board Headphone Amp Parts Preamplifier Musical Fidelity Kit AC12V 0.8A" - "TOPINCN 6J1 Vacuum Electron Tube Valve Preamp Amplifier Board Headphone Amp Parts Preamplifier Kit, Musical Fidelity, AC12V 0.8A by Lautaro Olive

I'm quite an electronics novice. There are many good assembly videos online. I used a multimeter to test my components. Everything else you need to know can be found on the board. Everything in my kit was good quality and easy to work with. The power supply that I bought with this unit is very noisy and cuts off the left channel. So it happened that I accidentally bought a similar pre-assembled unit before. The AC adapter that was bundled with the other device works great with this one. I don't know enough to point other buyers in the right direction, but I would suspect something was wrong with this unit if I didn't have a second (suitable) power adapter handy.