An undated file photo shows German famous composer Johann Sebastian Bach holds a manuscript in his hand. An Australian academic claims to have found evidence to suggest that the wife of Johann Sebastian Bach wrote several of the German composer's acclaimed pieces.

An Australian academic claims to have found evidence to suggest that the wife of Johann Sebastian Bach wrote several of the German composer's acclaimed pieces.

With over 30 years of research and applying more recent training from forensic police, Associate Professor Martin Jarvis says he can clearly show that Anna Magdalena Wilcke, Bach's second wife, wrote several of the manuscripts previously credited to her famous husband.

"I don't doubt that the 'cello suites' are not written by Johan Sebastian," Jarvis, who is also conductor of the Darwin Orchestra, told reporters.

The music detective became suspicious about Bach's work when he was a teenaged student at the Royal Academy of Music in London. While playing Bach's "cello suites" he became convinced there was something wrong.

"In 2001, I deconstructed the 'cello' pieces and came up with 18 reasons why they weren't written by Bach," Jarvis said.

Over the years, he said he found two famous 1713 Bach manuscripts in Anna Magdalena's handwriting.

"When you consider I found manuscripts that pre-date by seven years when she was supposed to have met him, you have to ask yourself what's going on here," Jarvis said.

His final breakthrough came when he obtained a copy of a manuscript. Applying forensic analysis, he examined it thoroughly and found the inscription "Ecrite par Madam Bachen" on the manuscript's cover in the handwriting of a musician friend of Bach's. The word means "written by," not "copied by."

"So you bring all these bits together and there seems to be overwhelming evidence that she was involved," Jarvis said.

Bach married Anna Magdalena in 1721. He died in 1750.