Review on Premium P1 Bluetooth 5.0 Vacuum Tube Preamplifier: Enhance Your Audio Experience with Hi-Fi Valve Headphone Amplification, Wireless Connectivity, USB DAC, and APTX-HD Support by Steven Saric

So getting to the point: the sound quality is good, nothing perfect but a bit of noise in the sound but that's coming from my computer sound card. What I really liked is the bass and treble controls, it's very useful and works great, the volume button works really well too. Now on to the physical aspects, I really liked this design, it's very beautiful and brightens up my office. The power button has a red power indicator. It also has three switches to select the handset's LED color (blue, orange, or OFF), the tone (ON or OFF), and the input (USB, RCA, or Bluetooth). The two tubes get a little warm when switched on, but not by much. The 3.5mm headphone jack is gold plated but doesn't work well with my headset due to some noise. The input options are very varied, you can use RCA, USB or Bluetooth, I tested everything and in my opinion USB is much better than RCA, but I just can't use the USB cable in my computer when I can use the USB cable plugs into the computer, another output option becomes available, but it's muted, and if you try to turn up the volume, it's muted again with any explanation. I am using an RCA cable but will use USB if possible. Now to Bluetooth. I didn't notice a huge difference in sound quality compared to RCA, but in my office Bluetooth had less interference than RCA because the only way to get the cable to my computer was to run the power and video cables together.