SDN Members don't see this ad. (About Ads) What are the subtle differences between these phrases? from my understanding, crackles is replacement word for rales. i've also heard of ronchi being thrown around. and then there's coarse breath sounds. I've used crackles for fine crackling sound like u'd get particularly at lung bases. coarse breath sounds kinda sounds kinda like a less high pitched sound--but can refer to any sound that doesn't quite sound right. anyone care to provide a more precise definition? thanks.