[CookieBoy]

Hi, I am a new member to this forum. I am also new to Nuprime/class D audio. Being an engineer, I thought, ‘there has to be something better than room heaters ie valve gear ‘ esp. when I am already living in the tropics. Well, I bit the bullet and purchased the sta-9. It’s been a year of thoroughly enjoying the amp every time we play it. It sounds great, it’s detailed and it runs relatively cool - what’s not to like it? But out of curiosity, if I want to upgrade it, which power amp is suitable for a guy who listens to most genre, classical to rock and jazz and has B&W 706 s2 speakers. Should it be the nuprime AMG or the st-10?

[rustydoglim]

ST-10 or AMG STA, that's a tough choice. I think you have to read several times the Amp Comparison Guide and the AMG STA Listening Impression section on the product page. They are like fine wine or cuisine, both are very fine products, just different.
The biggest difference between AMG STA and ST-10 is "Laid back" vs "Excitement".   

By the way, from engineering perspective, this is very difficult to do. Our Amp Design Guide (https://nuprimeaudio.com/guides/amp-design/) discuss the use of discrete transistors to craft the sound characteristic. This is part art part science and a lot of circuit simulation and device modelling, hard core analog electronics stuff that I don't understand.