At the end of a very quiet corridor, we open a door and are met by a burst of music, with 14 people standing and sitting, all engaged in rehearsal of Poor Ned, a 45-year-old ballad about Ned Kelly first created and told by Redgum.
The band singing it today involves 10 inmates at Cessnock Correctional Centre, learning the song under the tutelage of singer-songwriter William Crighton and original Redgum member John Schumann.
Singing lead is Pauly, an inmate who says it's his first time ever singing in a band. There's Sam on drums, Shaun on organ, another singer and rest on guitars - electric and acoustic.
Poor Ned, you're better off dead
At least you'll get some peace of mind
You're out on the track
They're right on your back
Boy they're 'gonna hang you high
The music workshop program has been active at Cessnock jail for the past five years, with twice a week classes involving inmates learning songs, learning instruments and writing their own new music.
Schumann was there on Wednesday as a special guest, pushing the men hard to shape the song and music.
Cessnock Correctional Centre Governor Brad Peebles was there, too, telling the invited media the program is a success and should be expanded.
Governor Peebles said many inmates were gifted musically and developing their skills was proving an instrumental part of their rehabilitation.
"Some of these offenders have never had the chance to cultivate their musical talents, whether that be playing instruments, song writing, or practicing their vocals, and when given the chance they excel," Mr Peebles said.
"Many inmates are very talented but unfortunately haven't put their abilities to good use. This is our chance to redirect their energy and focus into something constructive and positive.
"To have such a talented performer helping inmates hone their skills means they learn a lot very quickly, and our hope is that they continue to turn to this creative outlet once released back into the community - more music, less crime."
"It's good for your mental health, " says Pauly, who was singing lead on Wednesday. "This is the first time I've seen the Governor introduce this in all the jails I've been in."
"I've never done any singing. Now, I've been doing it a couple of months.
Pauly said he may even write a few songs of his own, probably about "coming out of the darkness into the light". Schumann called it "the best class I've ever taught".
"These guys are hungry," he said.
"They're dead quiet, soaking up everything."
Schumann complimented Crighton and his wife Julieanne, heavily involved and also in attendance on Wednesday, with "making the cake", as he called the workshop experience.
"I just smeared the icing on top of it," he said.
The jail band is rehearsing for a performance as part of NAIDOC Week at the correctional centre.
Governor Peebles said the music classes as just one of many "privileges" given inmates at Cessnock jail, in a social experiment that encourages learning new skills to improve behaviour and increase the inmates' chances of success once they leave prison behind.
He said project began at Macquarie Correctional Centre at Wellington in western NSW and is the subject of ongoing academic research into prisoner rehabilitation with the University of Melbourne and Flinders University.