Auckland's Holy Trinity Cathedral's organ rises from the grave

The great organ transplant at Auckland's Holy Trinity Cathedral is a step closer to completion with one of the final shipments of custom-made parts arriving from England on Tuesday.

The original organ wore out in 2014 and is slowly being rebuilt in a $4.5 million refurbishment.

Over 5000 pipes needed to breathe life back into the organ have been shipped over bit by bit from England.

"Everything is made by hand - you can't just go to Bunnings," says cathedral organist Philip Smith.

It has been crafted by Nicholson and Co. They've been around since Queen Victoria was on the throne - but this is their biggest project yet.

Mr Smith was there the day the music died.

"The rather tired and worn out blowers just gave up the ghost," he says.

"I had to accompany a thousand people singing their hearts out to 'Hark! The Herald Angels Sing' on a piano. It was anti-climactic."

The restoration is anything but. One side of the organ's already been revived and Newshub's camera took a peek at its intricate inner workings - the brain behind the musical heart.

After the installation the voicers come to make sure every pipe speaks perfectly and sounds good in the cathedral.

Mr Smith will be in on the debut performance, which is expected to happen in October. He hasn't chosen the piece of music yet, but says there will be a "getting to know you" phase.