Sisters Tegan and Sara Quin have come a long way in their 13-year career. With the release of their seventh studio album, 'Heartthrob,' the Canadian duo has embraced the indie pop-sound they hinted at on previous records. Both new and longtime fans have given their stamp of approval, making 'Heartthrob' the pair's highest-charting release.

Listening to Tegan and Sara's music alone wouldn't tell you that both sisters are openly gay artists. However, they are devoted supporters of LGBT equality and have donated their time at fundraisers and other awareness programs. Diffuser.fm sat down last weekend with Sara at Lollapalooza 2013 to talk about the evolution of the duo's music, their special performance with Macklemore at Osheaga and more.

We just watched a video of you and Tegan perform 'Same Love' with Macklemore at Osheaga in Montreal last night. Whose idea was it?

They approached us a couple of weeks ago and said Mary Lambert wasn't going to be at the festival. We love Mary and think she's amazing in that song, so we were a little nervous. But they asked us because we were doing our own show at Osheaga. We did, and it was amazing.

Canada is one of the few countries who has legalized same-sex marriage, unlike in the United States, where laws are a lot more fragmented. Why do you think that is?

The thing about Canada, and I'm playing Devil's advocate for the U.S., is that Canada is a much smaller country. We're talking about less than 40 million people. It's easier to govern, and I think it's easier socially to make change. We're a little quicker when you're dealing with a smaller group of people. Ten years have really changed the culture. There is an acceptance, not just a tolerance. That's remarkable, and I think that's what gives Tegan and I the confidence to spread the gospel stateside. We know that this is an important human rights issue, not a gay rights issue. And to see the States slowly following, these are big steps forward.

Do you see discrimination still evident within the music industry?

You know I think there are institutionalized discrimination, like sexism, homophobia and racism. The reality is that human beings are not perfect and we all have our issues. I try to remember that and still have compassion for the old ideas. But we are experiencing change. We've been doing this for 14 years, and I'll tell you, it's an entirely different landscape than it was when we first started out.

'Heartthrob' is your most pop-friendly album, which surprised some fans and critics. However, you and Tegan never denied being into pop music. Previous albums like 2009's 'Sainthood' and 2007's 'The Con' nodded in that direction. Was this a broad plan from the beginning?

I think we knew going in, like we always do with our records, sort of generally how our record was going to sound and what we were going to end up with. You know alternative and rock radio have always been our place. I think with this new album, we recognized there was a moment of starting to feel like we could get into the Top 40 and pop world, and it wouldn't totally seem out of the question. There's certainly a premeditated nature to what we do because you have to plan and have a sort of process. The music itself is fully in line with what we're listening to and excited about right now. To have that be heard on Top 40 radio is mind blowing. It's cool.

You and Tegan are turning 33 next month. What's the biggest difference being in your early 30s versus being in your 20s.

So much of my experience and confidence as an adult now in my 30s have come through the music industry. Ten years ago, we would have walked through here [festival press area] and not know anybody. These are our co-workers now in a weird way. We've done all of these radio and TV stations. We've played these festivals and we know these bands. I feel like we're in the place we belong now, and that allows me to be a more confident person.

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