LEIGH SALES, PRESENTER: For five decades Sir Elton John has endured as one of the great rock superstars.

He's the first to admit that his golden years were the '70s and '80s but he still puts on a hell of a show thanks to his extraordinary back catalogue.

For his entire career he's written the music and his partner, Bernie Taupin, has written the lyrics churning out hit after hit after hit.

To celebrate their extraordinary 50-year partnership, Elton John has released a record called Diamonds.

Sir Elton's been in Sydney and we met one afternoon.

(Music - Tiny Dancer, Elton John)

SIR ELTON JOHN: It's weird to think that 50 years have gone by because it seems like a flash to me now. It just seems like it was yesterday but it's not and so this is probably the last credited album I'll ever do.

(Music - Tiny Dancer, Elton John)

LEIGH SALES: When you're writing a song, how do you know that it's finished and that it's right?

ELTON JOHN: I wish I could explain it but I can't. It's just really strange the way I write with Bernie and I've never questioned it.

And do you know, we've never ever had an argument professionally or personally which is extraordinary because most songwriters sometimes split up because they get jealous of each other and it's exciting because it's never changed from the first day we wrote songs.

I still write the song when he's not there and then I go and play it to him. So the excitement is still the same as it was from day one and that's kept it fresh and it's kept it exciting.

LEIGH SALES: You mentioned 50 years has gone by. Do you ever pinch yourself and think, "My god, think about where I started and where I am today?"

ELTON JOHN: Yeah, coming here in 1971 and played Randwick Race Course and the stage blowing away and it seems like it was yesterday.

It's been an amazing journey but because there's been so much crammed into 50 years, there's been 150 years work crammed into 50 years, there's been a hell of a lot of work on the music side of things and a hell of a lot of other things in my other life.

LEIGH SALES: Does it still give you a buzz when you hear 200,000 people sing along with Rocket Man or a song like that or do you ever get used to that?

ELTON JOHN: It's gotten better. At the beginning of my career people used to sing along to Rod Stewart's records all the time and knew every word and I was so pissed off with him, not that it was his fault. I used to say to him "It's not fair, I can hear, you get the audience to sing and just hand the mic out" and as my career has gotten on, yeah, you can hear the audience singing Tiny Dancer, Your Song and it's wonderful and Crocodile Rock, of course.

And it's just thrilling, it's thrilling that a career has lasted this long and it's due to the fact that I do play live.

(Music - Rocket Man, Elton John)

LEIGH SALES: It must be exhausting though because you give, I've seen you live, you give so much.

ELTON JOHN: I have to and it is exhausting but it's not exhausting playing. It's exhausting travelling and there will come a time soon where I'll have to stop because the travelling is the hardest part for me and I'm 70 years of age and I've been in a van since I've been 16 years of age, and in the back of a van with a group.

I've been travelling all my life and it's brought me to so many wonderful places and brought me great success and I've loved every minute but to be honest with you I'm fed up with travelling.

LEIGH SALES: When your back catalogue is as well-loved as yours is, is it hard to then muster the confidence to play new material at concerts?

ELTON JOHN: Of course. Usually we call it the toilet break. "We're going to do a couple of new songs" and a groan from the audience.

We do two songs on the current, we have been doing it since Wonderful Crazy Night which was the last album to come out, Looking Up and A Good Heart and they really go down probably better than any new songs we've played for a long time. So we've kept them in. If they had died the death we would have dropped them.

Any major artist will tell you that as soon as, you can hear a perceptible sort of lull in the audience when you say, "Here is a new song. " But you have to otherwise you'll go crazy.

LEIGH SALES: Nonetheless I get the feeling that your audience is very warm and they're sort of willing to go wherever you take them, whether it's old or new material?

ELTON JOHN: It amazing. I mean, I'm lucky enough. I think the The Lion King contributed to it a lot, having grandmothers, mothers and grandchildren come to my concerts.

And the concerts I've just done in Australia have been a very, very young audience and I try to keep myself current. I do a radio show every week for Apple, I'm always promoting new songs.

I'm trying not to be an old fart - sometimes failing miserably.

After I do all these interviews today, I'm meeting Ruel, who is a 14, 15-year-old singer from Australia and Winston Surfshirt, who is a band I love who have a new album coming out and I've been able to locate them, playing new music on my show from Australia.

Angus and Julia Stone, another two that I play. There's so much good stuff coming out of Australia. It's really fantastic.

And focusing on that and helping younger artists is what I set my management company up for.

I mean Ed Sheeran was singing in living rooms when I first started and now look at him.

(Music - I'm Still Standing, Elton John)

LEIGH SALES: It's incredible to think, you know, isn't it that because music, you have that finite number of notes on your keyboard, great songs still keep getting written. You'd feel like at some point you'd run out of great songs to write?

ELTON JOHN: I don't think there are that many great songs being written, to be honest with you.

Occasionally you'll hear one. I think they're very much formula-like now and it takes seven or eight people to write them.

I think it's much more of a product now and much more of a, you know, it's very hard to get on the radio and they're very age conscious and you hear the same songs all the time and it's much harder for a new artist to get played on the radio than it was in my day.

I always tell musicians when they join the company you have got to go out there and play live, whether it is to 20 or 30 people, get some experience because at the end of the day, the record sales will eventually taper off when you get older and then you'll have something to fall back on.

LEIGH SALES: Did you always enjoy the performing aspect of it right from the start?

ELTON JOHN: Some nights you think you're going to be wonderful and then you feel great and it's okay.

Some nights you're tired and you think, "oh god. I'm not sure about that tonight" and you go on and it's just miraculous.

So that's the drug that keeps you performing, because you never know what great performance might come out of nothing and that's the reason you do it and also to get the feedback from the audience.

(Music - Crocodile Rock, Elton John)

LEIGH SALES: I read in a magazine profile of you where you said that you don't want people to think that you think you're trying to save the world but you do feel an obligation to try to help people in a less fortunate position than you.

How do you try to put that into practice in your life?

ELTON JOHN: I try to help out as much as possible. I speak out on issues that have been important to me like same-sex marriage, civil partnerships first in England. I never thought as a gay man that would ever happen to me.

It was an opportunity one couldn't turn down because it was a huge step forward, for gay people in Britain anyway and with the marriage it made it even bigger, it's not a flippant thing.

And I think most couples, gay couples that have been together a long time, enter into marriage because it's a hard-fought thing, they really treasure it.

I'm not saying that straight people don't treasure their marriage at all, I'm not saying that but because of the circumstances involved in same-sex marriage, and the fight we've had for it or the fight we're still having in Australia as well, then it's a privilege to be able to do it and it's made a difference to me personally.

LEIGH SALES: As you mentioned we're having this debate in Australia at the moment. There are a lot of gay people who feel depressed and down and as if their relationships are being judged. What would be your message to them?

ELTON JOHN: Be proud of who you are. I think the vote will be yes but times are changing. It means a lot.

Times have moved on and people do take it seriously. It's not just a flippant thing. It means a lot to people and to gay people out there who want to fight for it, I'm on your side.

And if people don't want it, that's their right too. We live in a democracy. I'm not saying that people shouldn't say no but I'm saying say yes because I know it worked for me and it will work for other people too.

LEIGH SALES: Sir Elton, such a great pleasure to meet you. Thank you so much.

ELTON JOHN: Thank you.