"I think for a variety of reasons, both personal and creative, I think we all felt like doing something we've not done before was really important," eldest brother and guitarist Isaac Hanson, 41, says, from the pop-rock trio's hometown of Tulsa.

"It was important to tell a different story about our band than we had and I think [new album] Red Green Blue is a great way to articulate that reality, which is both 'This is a colour format that makes all the colours of Hanson', right, but it's also three bold and uniquely different personalities . . . it's a little bit like you're deconstructing your own band in some way, you're trying to highlight something that you feel like maybe can get lost in the shuffle."

The independent band released their 12^th studio album Red Green Blue, or RGB, last month, almost 25 years to the day after their breakthrough single Mmmbop. It is the basis for an 87-date world tour that started in Finland on June 8, and will end in Australia and New Zealand in November.

Each brother wrote and produced a third of RGB - Isaac takes the lead on the green segment, Taylor, 39, on red and Zac, 36, with blue - with Grammy Award winners David Garza and Jim Scott as co-producers. While the brothers played on each other's songs, Garza also helped "fill in the holes".

"For all intents and purposes they are very much, they're about as close as any band can ever get to making solo records," Isaac says.

"Honestly, without breaking up, it is about as close as you could ever get to a solo record, because truly those sections on the record are really very much Taylor's vision, my vision, Zac's vision.

"It created a scenario where you could be as creative as possible without having what I would refer to as excess debate, because it was really a question of 'Hey man, do you feel this is serving your idea of the song?', not whether everyone's happy.

"This record is kind of like a giant trust fall, 'Hey man do you trust me? I hope so because here it goes' ...

"We certainly didn't squeeze the sponge dry by any means, but we definitely allowed for them to have unique enough flavour and unique enough personality that I think it articulates the point that I think all of us had hoped to make, which is [we are] a band of three lead singers, in some sense."

Isaac's green segment is "the most singer-songwriter I have probably ever allowed myself to be" and spans a range of styles, from acoustic ballad Write You A Song dedicated to his daughter Odette, through to the funk and soul fusion Cold As Ice.

But he says another track, No Matter the Reason, which tells the story of fighting for a relationship despite hardships, "may be my favourite song I've ever written".

He says there are songs on RGB that most likely would not have appeared on a Hanson album, but he was not consciously "trying to move away from something that Hanson is or is not".

"I'm just trying to make the best group of five songs I can make that speak the most to where I am at that moment," he says.

"If people learn something new about your band, if they hear something they like better than something they liked before, it's only a reflection of the fact that you put your whole self in."

RGB follows Hanson's 2021's release Against The World, which saw the brothers release seven songs over seven months, and 2018's String Theory, which re-imagined their back catalogue with symphony orchestras.

The trio is always looking for new ways of approaching their craft, Isaac says.

"If you're not feeling challenged, if you're not, shall we say, sore after the workout, then you didn't probably push yourself quite hard enough.

"I think we had enough trust in each other to strengthen the individual parts of this unit by doing a record like this.

"I would never say that this record was a walk in the park, it was not, it was actually one of the more difficult things I've probably ever done, but it was also one of the most rewarding things I've ever done."

Through the process, Isaac says, each brother learned new things about themselves and each other. He says Taylor and Zac "shared what they wanted to but nothing more than they absolutely needed to", while he preferred to float his ideas with the band.

"I think there were certain things about myself that I was afraid of leaning into," he says.

"I really play a certain role in the band that I feel very, very happy with in so many cases, but I'm also one to defer to other inspirations and other ideas because I have a tendency to be really of the moment and really like what the unit is bringing and sometimes the downside is that you find yourself, even though you've contributed significant amounts to what's going on, a little * a little bit less like you're in control of the outcome.

"That's not bad, but it does sometimes leave one feeling a little bit - there can be insecurity that you bring along with you and this allowed for me to ... conquer some of those demons of being a little bit afraid of finishing it exactly the way I wanted to and it being good enough in my own mind.

"Is this going to be OK for me to get this done this way?' And that shows a certain level of insecurity on my part, which I'm OK with talking about, because isn't that really where songs come from, some level of searching? Some level of vulnerability?"

Isaac admits that a 20-country tour in five months is ambitious, despite the band playing shows at home in Tulsa over the past two years that were live-streamed across the globe.

"You've got to get your sea legs again. I'm sure we'll fall right back into the rhythm of things and all that, but it is a little bit like going from running sprints to running a marathon," he says.