Audiophile – Listening chapter Audio Note M6 Phono.
Although the 5687 line stage valve is not as widely used as other vacuum tubes made during the same era in the world of hi-fi, Audio Note managed to put a spotlight on it and make it shine. Not only did the 5687 become exclusively used by Audio Note, it also became a signature for the brand. From that, one can see Peter Qvortrip and Andy Grove are two mavericks with their own style.