Well, actually, I don't think she was screeching or bellowing .... That would mean she wasn't managing her voice well and was singing badly, which would not be the fault of the genre or the composer. At the risk of identifying you with your characters, I gathered you have an affinity for orchestral classical pieces. Ditto for folk song. Are you averse to all sung classical music, art song included?
I think probably yes, I have an aversion to that kind of singing. I like singing that requires a singer to be in tune and have an interesting approach. But all that trained stuff. No. I don't like it at all. It's just me. I guess it's the same reason why I love folk dancing, and partner dancing to popular music, etc, but don't really enjoy ballet. It seems fakey. It takes a lot of training to do it ...but why? To me it's just a lot of impossibly thin people wrecking their feet by standing on tiptoe and throwing their arms and legs (and each other) around while striking poses. Fun for about 5 minutes.... This is my current favourite 'song' and style of singing ...Yo-yo Ma, Chris Thile, Edgar Meyer, Stuart Duncan and Aoiffe O'Donovan ...The Goat Rodeo Sessions. I think we've gone off the topic of italics? Just a tad....
Maybe you'll like this? Charlotte Church going a completely non-classical route It's kinda different.
Well, it was easier to listen to than operatic screeching ...although I can't say I was fond of it. Couldn't understand the words at all. No idea what the song is about, but that's another issue.
Meanwhile, back at the ranch . . . If the question is how to depict two people eavesdropping on two other people, another option might be something like this: "Hush!" said Mari, grabbing his sleeve. "What was that?" Dai froze and listened. From the other side of the thin wall he heard voices, faintly at first, then getting louder. No, closer. "Sounds like Nigel," he whispered. "And Camilla," Mari whispered back. He crept over and put his ear to the partition and motioned for Mari to do the same. "---infiltrate their meeting---" came Nigel's voice. Camilla's, answering: "---don't know enough Welsh. You think 'beth' is a girl's name, you prat---" "----studying on the BBC website---" "----hope so, everything depends on you getting that fool---" Dammit, Camilla, speak up! "Who?" he mouthed at Mari. "Eiron," she whispered back. So they thought Eiron was the weak link. He could be. He's just too nice. "---you worry, Nige, he'll tell us where Dai and Mari are hiding. Then we'll---" "---out of Cardiff, I know that. Quite likely they've escaped to Blaenau---" "Better change our plans," Mari said, her voice below a whisper. Dai nodded. "---know that, you silly cow. Let's give this place a quick search anyway---" The voices moved away from the wall. Towards the door! "The secret passage!" he said, urgently and low. With two silent steps he'd reached the power point that disguised the release. Mari was right behind.
Wow, there's a lot to play around with here: http://mymemory.translated.net/t/Welsh/English/beth Who knew?