Ага и Угу
I'm having some trouble with these words, and I'm sure they might have some nuance in what they mean in certain situations and such, but I more have a question about the pronunciation. The notes were alright, saying ага uses a fricative sound similar to uh-huh in English, and угу sounds like mhmm (for some reason).
But Duo's text-to-speech bot gave different pronunciations for ага, sometimes sounding phonetically like ah-gah, and sometimes with a fricative-sounding g like this: https://en.wikipedia.org/wiki/Voiced_velar_fricative
I checked forvo to see which one is more accurate, and most every recording in Russia sounded like an English uh-huh, except for one again sounding like ah-gah. Same kind of thing with угу too. See here:
Are these actual correct pronunciations somewhere? What is 'standard,' if anything?
Just for maintaining a conversation I'd say ''...ah-ah...uh-uh...'' but when I'm excited I might say ''Ah-gah! Here you are!''
The fricative pronunciation is most common. I chose Ага because I checked that the TTS pronounces it correctly (at least, in the sentences I fed it back then). It always failed with угу, so I decided it was not worth the effort.
It is important to understand that "Ага" and "Угу" just like "uh-huh" or, say, "haha" are just conventional representations of these sounds—the sounds that are not actually words, or at least not words made up of typical sounds of Russian or English. You are not actually supposed to pronounce them exactly as written.
Ага is similar to uh-huh, while Угу is the same with your mouth mostly or completely closed.
As a native Russian speaker, I'd say "угу" and "ага" are being used for same situations, for example — if you are agreed with someone then you can say what you want(ага or угу). It doesn't matter as far as I know.