It's simple - in recording, you build things: basic tracks, overdubs, mixes, projects, reputations, client lists, studios, empires.  Because recording involves microphones, nearly everything you record will pass through a microphone preamplifier.

Mic preamps are foundation equipment-your sound is built on them.  Literally.  Great foundation equipment helps build great recordings.  It makes sense to build your sound on a preamp that makes everything sound better - and that's why great mics love Great River!