Bethan Greaves started Kassia in 2003, with a women’s choir, and conducted their first rehearsal during the SARS scare. Initially she had about 60 women, but eventually it fell to 40 or so, she says, as many people left Hong Kong. “Some thought all the spitting while singing was rather dodgy. Some people even suggested that we wear face masks,” she recalls. It is a testament to her efforts and ambition that they managed to pull through the difficult period and stage their first concert.

All That Jazz was a hit, and many people sat up and took notice of this choir that didn’t do the traditional requiems and Latin masses. As Greaves says, “I know things we don’t want to do – when starting out I decided to offer something that wasn’t really on offer. Our first concert was just stuff that I loved.”

Nevertheless, Greaves was raised in the English choral tradition. “I started singing at church when I was very young, and sort of came up through that,” she explains, “so I’ve adapted that approach to the choir. Just because it’s pop music or musical theatre doesn’t mean we don’t have high standards.”

For the upcoming concert at the Sheung Wan Civic Centre on December 11 and 12, Greaves has chosen to premiere a piece specially written for the Kassia Women’s Choir. She felt that not enough good choral music was written for women, so she and other female choir directors banded together to commission Softly Little Child from Daniel E Gawthrop with lyrics by Jane Griner. Christmas themed songs and, of course, traditional carols will fill out the programme.

The Kassia Men’s Chorus will also be performing in the concert, once again joining forces with the women for O Magnum Mysterium by Morten Lauridsen. The two choirs have only performed together once before, during the Summer Fling concert. Not to be missed will be the men’s rendition of The Dance of the Sugar Plum Fairy.

The two choirs are part of Katterwall, the production and teaching company Greaves started about four years ago. Three other people now work with her as, along with directing the two choirs, she teaches music theory. “People think we sit around singing all day,” she laughs, “but it’s much more than that. We teach all sorts of things related to singing – Matthew teaches opera, and Camille is starting up the [children’s] choir.”

And Katterwall? Why such a… well, odd… name? Greaves explains she wanted the name of a sound or something music related for the company. “The options were dolce and allegro – I mean, ugh,” she says, screwing up her face. “How boring, so I thought maybe klaxon or katterwall, something different. In the end it was katterwall, a variation on caterwaul, middle English for a cat’s screeching wail.” Which reveals much about how Greaves feels about her music: it has to pack a punch and be full of surprises.

Underneath the Mistletoe will be performed at Sheung Wan Civic Centre Theatre on December 11 and 12 at 8pm. Tickets are $200, $180 concessions. available at URBTIX, 2734 9009