Question

two different techniques employed for producing sound

Answer 1

 "Bel canto" is beautiful singing. There are lots of people who claim to have a "bel canto" technique, who don't. Don't be misled. I am paraphrasing here, because I don't have it in front of me, but the great singer and teacher Mathilde Marchesi said in her "Vocal Method" something like: "A great deal is made of the German, Italian, French, etc. schools of singing. I have sung in the great opera houses of Europe, and I can tell you that there are only TWO schools of singing. The GOOD, which produces beautiful, healthy sounds, and the BAD, which produces ugly, unhealthy sounds." That is just as true today. Good singing is supported, focused, free of tension, balanced, coordinated, facile, etc. Bad singing is not. The end.