I bought this headphone amplifier back when my previous audio interface only had one headphone out. This one is super simple to use, it has 5 female jack plugs, 1 in, 4 out, all stereo. All outs have a dedicated volume which is nice for matching volumes to each one's preferences. Sound wise it is clear and doesn't colors sound, at least to my senses.
It is small, affordable and comes with dedicated AC converter/transformer. It does all that it is intended for. Verdict = BRILLIANT.