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LAGUNA BEACH, Calif. -- More than 6.5 million people have signed up for Apple Music since the $10-a-month streaming music service launched at the end of June, CEO Tim Cook said Monday.

Another 8.5 million people are participating in the music service's 90-day free trial, he added.

"I'm finding personally that I'm discovering a whole lot of music that I wasn't listening to before," he said. "I think it's fabulous. And to have over 15 million on there, and 6.5 million in the paid category, I'm really happy about it, and I think the runway here is really good."

Cook made the remarks during a wide-ranging interview here at a Wall Street Journal technology conference. Along with comments about Apple's new services and products, Cook spoke passionately about the company's responsibility in promoting human rights, improving the environment and touting education. He added that he doesn't mind irritating people as long as Apple is upholding the legacy of company co-founder Steve Jobs, who wanted to change the world with tech.

"If we piss a few people off, I think at least they'll say, 'They made a great product, and I may not agree with this or that, but I respect that they are trying to leave things better than they found it.' At least, that's what I hope they say," Cook said.

Apple Music offers streaming music with playlists curated by "music experts," a 24/7 radio station called Beats 1 and a social feature called Connect that brings together musicians and their fans.

Cook touted Apple Music's benefits over rivals like Spotify, which has 20 million paying users.

"We have music experts, just like the DJ when we were growing up...that are deciding what's next," Cook said. "It brings the art back in music."

Apple TV orders start next week

Cook also revealed that Apple will start taking orders for its updated Apple TV on October 26 and will begin shipping the set-top box by the end of next week. Apple last month unveiled a new version of the video streaming box , adding long-awaited features such as an iPhone-like app store, a touch-enabled remote and the ability to simultaneously search for content across multiple video providers like HBO, Netflix and Hulu. The box, priced starting at $149, also adds support for Siri, Apple's digital voice assistant.

While the new Apple TV isn't launching with an Internet-based TV service, as many had requested, Cook said the company is trying to fix a "terrible, broken process" that no one likes. "You have 700 channels, but you can't find anything you want to watch," he said.

Cook on cars, activism

After expanding into new product categories over the past year, such as mobile payments and wearable technology, Apple also is believed to be working on car technology. Autonomous car technology has become a big focus for companies such as Google and Uber, and speculation about Apple's self-driving car plans has been swirling for months. The program is believed to be code-named "Titan" and to involve hundreds of engineers.

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Cook didn't give away any secrets but acknowledged that cars are a focus for Apple. He said that software is becoming an "increasingly important component of the car of the future" and that autonomous driving will become "much more important in a huge way in the future." Initially, Apple's focus on cars is centered on making sure drivers have an "iPhone experience in the car" through the company's CarPlay technology, Cook said. He didn't say what the longer term focus is but hinted it could be significant.

"I do think that industry is at an inflection point for massive change, not just evolutionary change," Cook said.

Asked about his activism as CEO, Cook said that supporting human rights and the environment is the right thing to do.

"We want to give back," Cook said. "Our culture is to leave the world better than we found it, and we try really hard to do that."

He also talked about Jobs, who brought Apple back from near death in the mid-1990s and turned it into the most powerful and valuable technology company in the world.

"Steve formed Apple to change the world," Cook said. "This was his vision. He wanted to give technology down to everyone and empower everyone to use it. He wanted to take it out of the glass house and the big corporations, the rich people that had the technology, and sort of bring it to people and empower them to do great things. We still have this. That is still our drive."

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