Adrian Eagleton cannot string a sentence together after experiencing a stroke 18 years ago, but like many of the members in Stroke a Chord, he can sing beautifully.

In a condition known as aphasia, the stroke damaged the section of his brain that controls speech output.

But because singing and melody is processed by a different part of the brain, he is still able to sing.

The 66-year-old is a member of Stroke a Cord, a choir for people who also have the condition, which is celebrating its sixth birthday this week.

To mark the occasion, they performed a rendition of Unchained Melody, complete with one of Adrian's moving solos.

Yooralla speech pathologist Bronwyn Jones said it regularly brought a tear to the eyes of their audience.

"Adrian has got five words, and several of them are rude words, and that's about it," she said.

"But when he sung Unchained Melody he was able to sing a whole verse all by himself.

"His sister came over from Adelaide when we first were rehearsing, and she cried the first time she heard him sing.

"We haven't done our job unless Adrian's brought a tear to peoples' eyes."

Ms Jones has been working with the self-funded group since it started in the eastern Melbourne suburb of Ringwood in 2000.

She said it was touching to see participants finally being able to express themselves using their voice.

"It's just a joy every week, it's like magic, it's like coming to work and seeing magic."