I asked Ola about his interest in the Contralto voice:
"It goes back to the 60's, when our cathedral choir in my home city Trondheim regularly performed Bach's Christmas Oratorio. Some of the most beautiful arias [in the work] are given to the alto."
Indeed they are! Does he have a favourite Contralto?:
"I don't think I prefer one above all the others, but I think that Kathleen Ferrier is unique."
So, which Contraltos have been added to the Contralto Corner? Well, their names are Birgit Finnilä, a Swedish Contralto, and French Contralto Delphine Galou.
There is precious little out there about these two women on the internet. If anyone has any links I can add to these pages, please let me know.
Thanks again to Ola for writing in!