Elgar took up the trombone aged 43
Sue Addison, the lead trombonist in the Orchestra of the Age of Enlightenment, is collaborating with a Reading pianist to perform Elgar's music on the trombone.
The English composer took up the instrument aged 43, but never really mastered it.
He donated his trombone to the YMCA, for use by troops at the front during World War II.
The instrument eventually passed to the Royal College of Music.
Now the trombone is on loan to Sue, who has been researching the story behind Elgar's trombone, and creating a series of recordings of Elgar and Holst played on the brass instrument.
She told BBC Radio Berkshire's Anne Diamond that Elgar was notoriously bad at playing the trombone.
"He took up the instrument at the age of 43, but sadly he never really mastered the instrument," said Sue. "A really good friend of his, Dora Penny, helped him a lot to proof read his music, and one day he decided to go to the corner of the room, pick up a trombone and play a few notes from the score.
"He couldn't hit the note, she burst into laughter, and he said 'how do you play this blasted thing?"
Elgar donated his trombone to the YMCA along with thousands of others during the Great War, so that soldiers could enjoy music while fighting during the war.
But Sue said there were some 'missing years' from the period between the trombone was donated to the YMCA and when it was acquired by the Royal College of Music in 1934.
She said that having the trombone on loan had 'inspired her' to get to know more about Elgar and his music.
Sue said: "Elgar must have liked the sound because he wrote beautifully for it in many of his symphonies.
"This is the trombone that he probably learned to play on."