According to oregonpapa, our resident fuse expert and beta tester of a newly developed fuse, the QSA yellow fuse has a noticable thinness in the midrange. His "golden eared" friend, without knowledge that he was listening to the QSA fuse, noted it also:.
Both ways, the QSA Yellow fuse sounded dynamic, transparent, went deep in the bass, but I still can’t get around that thin (for lack of a better word) midrange.Based on the glowing testimonies from many of the other QSA users, one concludes that their systems may not be resolving enough to highlight this sound signature or ears good enough to hear it. In any case, if it doesn't bother it appears the other sonic advantages over the SR fuses are enough to justify the QSA purchase price anyway. Although some strive for a "magic midrange".
The last time he was over, I was just breaking in the first QSA Yellow fuse in the line stage. He heard the abnormalities in the midrange too, so we swapped out the fuse with the SR Orange fuse that was previously in the line stage ... and the music came back into focus
like before.