I owned for quite some time the Shunyata Sigma 2. I thought they were dull sounding, no excitement in dynamics, soundstage etc.
Currently I own the AQ Thunderbirds. They took quite a while to fully burn in, but today, I am really amazed at how well the soundstage is lit. At times when there is a solo guitar or a sax etc. it seems like it jumps out at you. Very impressive. Never experienced that with the Shunyata's.
I now own both the AQ Thunderbird XLR interconnects and the Zero and Bass speaker cables. BTW, I also have AQ Dragon power cords and the AQ 7000 power conditioner. So, perhaps there is quite a bit of synergy going on.
ozzy