I regret not recording it, I tried looking up what species it was, but people are saying its synthesized. I can say that its plausibly not. I heard them in the state of Washington. Their chirps echo as they talk to each other, just like the song. I thought it was some sort of after effects, but no, it was trippy.
Near here (link deleted), and it was yesterday.
I was in woods. After looking up bird calls, I think the echo was caused by the woods themselves, and I just happen to be in an area that gave the same echo pattern as the song.