Question: What was the original name of the opera diva dame that the Melba Memorial Conservatorium was named after?

Context paragraphs:
Olive Fremstad: Olive Fremstad (14 March 1871 – 21 April 1951) was the stage name of Anna Olivia Rundquist, a celebrated Swedish-American opera diva who sang in both the mezzo-soprano and soprano ranges.

Marcella Sembrich Opera Museum: Marcella Sembrich Opera Museum, also known as The Sembrich and the Marcella Sembrich Memorial Studio, is a historic teaching studio located at Bolton Landing, Warren County, New York.  It was built in 1922-24 as a teaching studio for New York Metropolitan Opera diva Marcella Sembrich (1858-1935).  The studio building is a one story, rectangular, stucco walled wood frame building with a hipped roof and glassed in porches in the Spanish Revival style.  Additional contributing features on the property are a bathhouse, curator's cottage, a lookout, stone retaining walls along the shoreline, stone walls, three piers flanking the entrance, wrought iron fencing and entrance gate, and landscape features.  The property was converted to a museum shortly after the death of Marcella Sembrich in 1935.

Nomeda Kazlaus: Nomeda Kazlaus (born as Nomeda Kazlauskaitė in Vilnius, Lithuania) is one of the most outstanding Lithuanian operatic sopranos of the contemporary generation of singers, an international opera diva who has appeared in leading roles in many European opera houses including the Gran Teatre del Liceu in Barcelona, the Mariinsky Theatre in Saint Petersburg, the Bolshoi Theatre in Moscow and the Teatro Malibran in Venice.  Nomeda Kazlaus is also TV host, vocal professor, jury chair and member of many international competitions, laureate of four international singing competitions, winner of the Lithuanian Ministry of Culture Young Artist 2007 award.

A Lady's Morals: A Lady's Morals is a 1930 American Pre-Code film offering a highly fictionalized account of singer Jenny Lind.  The movie features opera diva Grace Moore as Lind, Reginald Denny as a lover, and Wallace Beery as P. T. Barnum; Beery would play Barnum again four years later in "The Mighty Barnum".  The film contains some fine opera arias by Moore and was directed by Sidney Franklin.

Melba toast: Melba toast is a dry, crisp and thinly sliced toast, often served with soup and salad or topped with either melted cheese or pâté.  It is named after Dame Nellie Melba, the stage name of Australian opera singer Helen Porter Mitchell.  Its name is thought to date from 1897, when the singer was very ill and it became a staple of her diet.  The toast was created for her by chef and fan Auguste Escoffier, who also created the Peach Melba dessert for her.  The hotel proprietor César Ritz supposedly named it in a conversation with Escoffier.

Melba Memorial Conservatorium of Music: The Melba Memorial Conservatorium of Music was a school of music located in Melbourne, Victoria, Australia.  During its early days it was closely associated with opera diva Dame Nellie Melba, after whom it was later named.  In 1994 it became affiliated with Victoria University.  Founded in 1901 as "The Conservatorium of Music, Melbourne", the Melba Conservatorium ceased teaching at the end of 2008.  However, it finds its continuing expression in the form of Melba Opera Trust.

Joan Carden: Joan Carden AO OBE (born 9 October 1937) is an Australian operatic soprano.  She has been described as "a worthy successor to Dame Nellie Melba and Dame Joan Sutherland" and was sometimes known as "the other Joan" (a reference to Sutherland and Dame Joan Hammond) or "The People's Diva".  She was a Principal Soprano with Opera Australia for 32 years, and was particularly associated with the title roles of Giacomo Puccini's "Tosca" and "Madama Butterfly".  However, she sang over 50 other roles, from the 18th century, including virtually all the Mozart heroines, through to works by contemporary composers.

Nellie Melba: Dame Nellie Melba GBE (19 May 186123 February 1931), born Helen Porter Mitchell, was an Australian operatic soprano.  She became one of the most famous singers of the late Victorian era and the early 20th century.  She was the first Australian to achieve international recognition as a classical musician.  She took the pseudonym "Melba" from Melbourne, her home town.

Glen Carter-Varney: Glennis Carter–Varney (born 12 May 1938) is an Australian composer, pianist and educator: formerly as Head of Contemporary Keyboard studies and lecturer in piano at the Melba Memorial Conservatorium in Melbourne and as Music Director at The Scots School in Albury, New South Wales.  She also taught class music at Methodist Ladies College in Melbourne and directed her own private music schools in Melbourne and Brisbane.  She has produced musicals, trained choirs and madrigal groups, performed as a soloist and recording artist, and her experience is wide and varied.

Melba, Australian Capital Territory: Melba is a residential suburb in the Belconnen district of Canberra, located within the Australian Capital Territory, Australia.  The suburb of Melba is named after Dame Nellie Melba (1861-1931), the first internationally recognised Australian opera soprano.  The streets are named after composers, singers and other musically notable Australians or people with strong Australian connections.

Supporting paragraphs: Melba Memorial Conservatorium of Music Nellie Melba
Answer: Helen Porter Mitchell