I upgraded mine to a BAT VK-52SE pre and hypex NC400 amps because i wanted multiple balanced outputs so I could run my headphone amp. I also wanted to see what all of the "hype" was about with the HYPEx (pun intended) and wanted to try my hand at DIY.
The hypex is indeed a phenomenal amp, but so is the STI series.
I kept the STI-500 and moved it into my bedroom to drive my old speakers. The BAT/ hypex is a bit better but it is definitely pretty far into the area of diminishing returns. I think dollar for dollar, the STI series is among the best bang for your buck in hifi, along with OPPO as a source.
The hypex is indeed a phenomenal amp, but so is the STI series.
I kept the STI-500 and moved it into my bedroom to drive my old speakers. The BAT/ hypex is a bit better but it is definitely pretty far into the area of diminishing returns. I think dollar for dollar, the STI series is among the best bang for your buck in hifi, along with OPPO as a source.