The 39-year-old rocker admits he felt ''completely lost'' after the band's 2007 record 'Era Vulgari' and called upon the skills of the fellow musician for their upcoming offering '... Like Clockwork', in which Trent offered his vocals to the track 'Kalopsia' and agreed to produce after the pair bonded in the studio.
Josh told NME magazine: ''I didn't know if I could make a record again and I don't know why, but I called Trent. I wanted him to produce the record and I didn't have many songs or know what I was doing and was completely lost.
''I just said, 'Man, you wanna have some coffee?' and he came to my studio [Pink Duck Studios in LA] and we talked for about five and a half, six hours.
''We were just acquaintances before but he's funny and smart and honest and a good communicator, you know. And we did it again, and again. And I talked him into producing the record.''
After feeling more confident, the flame-haired musician and his bandmates - Troy Van Leeuwen, Dean Fertita and Michael Shuman - worked long and ''hard'' recording the tracks to make sure each song had a unique feel.
He added: ''It took so f**king long. Every song is like a person. They need to be presented correctly. It's a bit like being a miner - not meaning a young person - in that you're doing your best to uncover the gems of what you don't understand, and it's hard work.''