“Pre-Raphaelite,” I said last time someone asked me what Loreena McKennitt was like. “Like a woman who would sing the Lady of Shalott.” When McKennitt is at her best then the grave, mild tenor of her voice illuminates her compositions with a courtliness that dignifies their subject matter. On this Christmas album, which expands, by eight tracks, her five-track 1995 EP A Winter Garden, the courtliness seems unnecessarily flowery. The instrumental pieces rarely rise above the level of ordinary prettiness. Instruments enter slowly, plainly, as if each tune is a conversation and they are trying to mime it to a deaf mute. A more varied pace would have been welcome. She has made better albums than this.