Review on 🎧 Sabaj PHA3 Vacuum Tube Headphone Amplifier: Enhanced Stereo Amp for Immersive HiFi Audio Experience with Low Ground Noise and Headphone Output Protection by Courtney Ellis

Vacuum tubes do a good job of adding warm analog characteristics to the audio signal from your digital device. But the output stage is a pair of op amps that do almost nothing to boost the sound beyond the input level. So if you are already satisfied with the volume without this device and only want "tube sound" instead of "sound card sound", you will be very happy with this one. However, if you want analog tube sound AND enough gain to make a noticeable difference in headphone volume, you need to look for a real amp, preferably one that uses power tubes rather than op amps in the output stage. I'm giving it three stars because the sound quality improvement is very nice, but be aware that it won't do you much good as an amplifier - your headphones will have about the same maximum volume as without this unit.