Review on 🎶 Fosi Audio P1 Tube Pre-Amplifier Mini Hi-Fi Stereo Buffer Preamp 6K4 Valve Vacuum Pre-amp with Adjustable Treble and Bass Tone Control for Enhanced Home Theater and HiFi System Experience by Karen Gaiser

I was about to withdraw my 3 star rating because the preamp was able to add a nice touch to the sound and I kept it. At first it was almost returned because it didn't work. I raised the stars out of a sense of justice. HOWEVER, I WILL NOT USE CAPITAL LETTERS TO MAKE MY POINT. Pipe heat is exactly that. It's not the same as flavoring the highs and lows (which makes this unit excellent for a sub-$50 unit). If tubes are used in the amp, this should smooth out the waveform; This mitigates the cold, hard, and dry characteristics of some digital audio. However, this is not the same as adding so-called "warmth” in a subjective sense. When listening to professional audio gear, tubes add a slightly fuzzy quality to the sound (the amount can often be adjusted). Fluff does not pass through this device. Because of this, one reviewer wrote that he wondered if there was current flowing through the tubes.