i currently have rme adi 2 and hd650. First i tried with smsl sp200 but it didnt do a great job other than high volume. The sp200 really disappointed me now im really lost. So now im sticking to topping a90 which will arrive next week. Im hoping this will drive hd650 or even other high ohm headphone perfectly. But If this doesnt do a great job Im leaning towards to purchasing a used spl phonitor 2(Around $1000). Many people recommended getting a otl tube amp but its high maintenance and too complicated i want a simple solid state amp. what are your experience with spl phonitor 2? Will this pair well with hd650,800s,t1 or even clear focal? im really having trouble find a perfect amp with limited budget and knowledge. Thank you!