Yamaha is well known brand, mostly for the its important place in moto industry but not only. Most know that this Japan brand is manufacturing audio equipement as well. A very good audio equipment. Yamaha A-05 NS series is not that well know, honestly speaking it is not know at all. Finding anything about this segment on the internet is like finding a needle in a hay stack. Silver metal panel, with very nice display which in the night glows in green, solid metal chasis, what else... Simple inside, smart and nice outside and you got yourself a nice amp.
Simple amplifier with simple sound, nothing extraordinary, but on the other hand what do you need more from it. It will power up your speakers with any kind of music.