The Louder You Feed an Analogue to Digital Converter, the Better It Works?

Some say the louder you feed an analogue to digital converter, the better it works. Is it one of those inerty myths? Also, is there special reproach regarding input output levels when using a combination of analogue outboard and vs? Ts? George raman tanis romatnus: I'm like, who's saying this? Som where are you geting this information?