Okay, this thing is better than I'd hoped for...every bit as good as the Waza-Air-B, the only real difference is the Air-B is completely wireless.
I haven't even explored all the features because there's simply so much 𝘵𝘰 explore.
Nothing else in the headphone amp comes close...my Fender Micro Headphone Amp is already boxed up and ready to ship, sending it to a guitarist friend.
Vox, Nux, Blackstar, Flamma, Joya, etc, if you're looking for a bass headphone amp, forget about them and go with the best...incredible bargain for $125/£95.
Sounds amazing even with bargain-priced headphones...Silensys E7.
Hard to find a bass-specific video but this should give you some idea.
https://youtu.be/ruLZC4wbK58?si=IURVaL_c8Oq5q2nT