Cetalinguistic translator

The study of cetalinguistics - the language of whales - has long been a part of Tesheli society, especially among the dolphins and the balaceti. Whalesong influenced the development of the balaceti's own language, as well as their culture. But it wasn't for some time that concrete translations of whalesong were made possible, when an ancient undisturbed glyph crystal was found that had absorbed a conversation between a whale, an orca, and a balaceti.
After the glyph was analyzed, the field of cetalinguistics was finally formalized. Balaceti travelers set about reanalyzing old whalesong, and silverfin hydromancers developed a way to replicate the acoustic storage properties of glyph crystals using compressed spheres of water. Working together with orca historians, the first aquacoustic library was founded.
The libraries need people in several different roles to function - guards, recorders, hydromancers, and librarians - but none are held in higher esteem than the translators. Whales were already held in reverence by the people of Teshelyn, but the ability to understand their songs was a major cultural paradigm shift. If the whales are living gods, the translators are their harbingers. Translators come from almost every sentient species of Teshelyn, but balaceti translators are the most numerous. Orca translators make up most of the others, with a handful of dolphins reaching mastery as well. Human translator exist but are very rare, possibly due to human hearing being different in important ways from dolphins.
Merfolk, on the other hand, completely reject the notion that whalesong is meaningful. Though they do have respect and reverence for whales, they consider the culture surrounding them to be based on myth rather than fact, and they think that whalesong is a rudimentary form of communication between beasts.