A mixed response: About 30 years ago, a noted chanter from the Metropolis of Athens---Greece, visited my parish and chanted the terirem, loudly, his mouth close to the microphone. (His chanting otherwise was beautiful.) I couldn't believe this was something acceptable in an Orthodox Church; it sounded like a rock version of ecclesial chant. I don't think it's even proper to express how inappropriate I thought it sounded. It was done during the Divine Liturgy, after "Praise the Lord...," while the priest communes. However, there is some terirem executed on YouTube, from a Mt. Athos monastery, perhaps what is linked above, that I found quite pleasing to my ear, melodious, and appropriate to the church.