Review on 🎧 Fosi Audio P2: Vacuum Tube Headphone Amplifier for Unmatched Hi-Fi Stereo Audio Quality with Low Ground Noise and Output Protection by Kelz Dixon

The value for money is hard to beat, especially in the world of tube amplifiers. It's a "hybrid" in the sense that it uses tubes for the preamp stage and ICs (operational amplifiers) for the gain stage. As you can see in the photo, you can roll Ruby and OU. There is 1 chip per channel, so they must be bought in pairs. I've tried this with a few different tubes - standard tubes as well as some popular Mullards, as well as a few different pairs of op amps. The differences were minimal. In terms of audio quality, I found it to be very quiet, if a bit "thin" or "thin" compared to my Little Dot 1+ (which is almost twice the price). It doesn't get super loud either. If you have demanding headphones or like to listen at high volume, you should look elsewhere. I suspect it could be the power adapter. Judging by the build quality, it's well built. The volume control is "graduated" so you'll hear a slight increase with each step or "notch" on the dial, rather than a gentle increase (as you'd feel with something more premium). Overall, this is solid value for money and a good entry-level headphone amp.