I'd check my fan profile before I do anything else. Yes they are not the quietest but then again if they are always running at full speed...
From what I've seen and read, the Noctua Industrial are the best relatively quite, with the best static pressure, but you do pay for what you get. The SP120L on the Corsair at 37.5db at full speed with very good static pressure is a really good compromise.
Remember that radiators are all about static pressure, just try throttling them back a bit, so they are not running at full speed all the time.