The rhythm game genre seemed unstoppable for a number of years as both Activision's stable of developers and Harmonix cranked out sequel after sequel to the Guitar Hero and Rock Band franchises, respectively.

Fans bought game after game, along with expensive plastic versions of musical instruments so they could pretend to be in a rock band while pretending to play music in their living rooms.

Then, nearly as suddenly, it all stopped. Harmonix moved onto other projects, and Activision shuttered or collapsed a number of studios that were working on the Guitar Hero series. The era of plastic instruments ended not with a bang, but with a whimper.

It's been a little under five years since the release of Rock Band 3, and the whispers of a new title and the demands of players who have no rhythm games to play are becoming overwhelming. After hinting strongly that something big was in the works, Harmonix is officially saying it's time to get the band back together.

Rock Band 4 is coming, and you'll be playing it this year.

The Rock Band team has been spending a significant amount of time playing past Rock Band games, trying to find the heart of the franchise. What they discovered was that later games suffered from a sort of feature creep: There were too many things bolted onto the sides, with few changes to the core mechanics.

"None of the games in the genre really delivered a lot of innovation, or maybe the right kind of innovation in the experience during that period. Consumers want something new," Harmonix co-founder and chief creative officer Alex Rigopulos told Polygon. "We view it as a responsibility to deliver that innovation this time around."

The challenge is maintaining the core of Rock Band while delivering those unnamed new experiences.

"I am consistently surprised by how few people are bored with that stock game, you know? I'm psyched about it. We can really lead the charge with the new things we're doing, but the things that people really care about are these platform issues that differentiate Rock Band as a title," product manager Daniel Sussman said.

Harmonix is claiming that the sprawl of Rock Band 3 will be replaced by a more focused experience that moves the series ahead on a number of levels. The push to get people learning how to play actual instruments will be set aside to focus on the arcade-style fun of the earlier titles.

"There is an existing gameplay core that is very powerful and very fun, and we don't want to tamper with that core. At the same time, we need to bring something new to the experience," Rigopulos said.

He listed three parts of the experience. One is the chase for the highest scores and most precise playing, which a "passionate minority" of players thinks about. Then there are the people who play Rock Band like a party experience, without much care for the "game" aspect of the title.

"The living-room party experience, the multiplayer, drunk party fun with rock and roll, these people don't care about score at all," he said. "[For them] it's all about having fun and making rock music with a group of friends."

The third focus is on the narrative progression of the game, the story that takes you through your career as a virtual rock star.

Those three aspects of the game will be the focus of Rock Band 4.

Your songs will carry over

Your downloaded songs will work through console families, so PlayStation 3 content will work on PS4, and the same with the Microsoft consoles. Now it's a matter of making sure the library works in the new game, while also figuring out the licensing for the existing content.

Harmonix is dealing with not only DLC, but also songs you bought in a previous game that could be used in later games and will now be used in the latest game on a new platform. This is another area where they're working with first parties, but have many issues they have to solve themselves. This sort of thing is a unique challenge, and one that doesn't have many existing best practices.

"The work is going really well. I'm confident that we'll get there. Players who have a good-sized library of DLC, it will show up day one and they'll have their songs," Sussman said.

Harmonix can't talk about specific terms of these deals, but Sussman described it as a "rolling set of licenses," some of which are easier to renew than others. He estimated that over 95 percent of Rock Band's library of songs will make it over into Rock Band 4.

What about your existing instruments? Accessory manufacturer Mad Catz will be creating new instruments for the game, so you can look forward to purchasing new guitars and drums if you'd like. But there is also work being done to make sure your existing instruments are backward-compatible. Harmonix says it's working "aggressively" with Sony and Microsoft to make that happen. "The Sony instruments were wireless via a USB dongle; that's pretty straightforward. Things are complicated on the Xbox side, and I'm not prepared to talk specifics yet until I understand them a little better, frankly. There's a first-party component, and a technical component being managed by Harmonix and Mad Catz that is still very much in play," Sussman told Polygon. "Harmonix are working tirelessly to ensure that gamers can make use of legacy music and DLC that they purchased last time around and so [too], we are doing all we can to try and make last-gen hardware compatible with Rock Band 4," said Alex Verrey, global public relations and communications director for Mad Catz. "The current generation of console hardware, however, is dramatically different from last gen — presenting a new set of compatibility challenges," Verrey continued. "Rest assured, however, that we hear the message loud and clear and we're on the side of the gaming community. It's an ongoing effort and we'll do everything in our power to try and ensure compatibility wherever possible." So it's very likely that the instruments in your garage or basement will work on the current-generation systems, but exactly how that will work, or if there will be any limitations to that compatibility, are still up in the air. It's a hard situation for a developer or publisher to be in, because so much of the work depends on what Sony and Microsoft will do themselves, or will allow to be done with their respective systems. Sussman dismissed claims anyone was being hard to work with, however. "Nobody is going out of their way to make this difficult. We're dealing with cutting-edge technology; it's all kind of emerging," Sussman said. "It's just really complicated." Update: Harmonix has confirmed the keyboard will not be returning in Rock Band 4. "Rock Band 4 will focus on the core experience and the roots of the franchise — guitar, bass, drums, and vocals. There will be no Pro Guitar or key support in Rock Band 4. We will continue to support "Pro" mode for Drums," the company said in a statement. What about the new hardware? "We'll be discussing the hardware in much more detail as we approach launch but at both Harmonix and Mad Catz there was a mutual desire to strip the experience back down to the core: What made Rock Band so much fun to begin with?" Mad Catz's Verrey said. "The emphasis was therefore shifted to creating the worlds' [most] fun and inclusive party-based music experience, so we're not pushing forward with complex pro-instruments or anything which we feel will alienate fans who just want to kick back and have some fun," said Verrey. "We want to do something new, we want to [be] innovative and prove interesting, but at the same time, we don't want to reinvent the wheel and drastically alter the Rock Band experience." "At first glance, the hardware may look familiar, but behind the scenes several key improvements have been made," he continued. The tilt function that activates overdrive has been improved, and they're working on improving latency. You'll be able to purchase Rock Band 4 in a number of ways, but only a few have been announced, including: • The Band-in-a-Box Bundle, which includes the Rock Band 4 game, a Wireless Fender Stratocaster Guitar Controller, a Wireless Drum Kit Controller and a Microphone. • The Guitar Bundle, which includes the Rock Band 4 game and a Wireless Fender Stratocaster Guitar Controller. • A special Wireless Stratocaster Guitar Controller, featuring custom artwork of "Gabe" from the Penny Arcade webcomic. This limited-edition collectible will only be available via on-site pre-orders at the Harmonix booth during PAX East. Mad Catz also talked about the need to keep things from getting as ... intense as they were in the past with the peripherals. The amount of add-ons and options will be kept to a minimum. "We're very conscious of the fact that instrument hardware is a considered purchase, and many consumers may be wary about overdosing on too much hardware too soon into the new console life cycle," Verrey said. "That's why, as said above, we're keeping things focused. No 'Pro' hardware, no carry cases, no additional peripherals at this point. Announcing the game and hardware at PAX also gives us ample opportunity to begin gauging demand from gamers as we ramp up production."

The crash So why did rhythm games go away for so long? "One can only theorize, and lots of people have theories about this," Rigopulous said. There is, of course, one theory that keeps going around. "Activision oversaturated the genre with too many releases, people fatigued, and that's why it fell away," he said, listing one popular theory. "There's probably an element of truth to that, but I think the real picture is much more complicated." The decline began with the onset of the recession; band games were very expensive, and selling them into a recession was a factor in the drop-off. There is also the unsexy question of inventory management, an aspect of the gaming business that's rarely discussed. It's one thing when a company is printing discs and plastic cases; the cost per unit is low. Rock Band and Guitar Hero lived and died around the sale of expensive, large peripherals. We live in a digital world, and plastic guitars and drums are expensive to create, ship and put on store shelves. "One of the big contributors to the 'downfall' of the genre was that we did not effectively manage our inventory," Sussman said. It's the economics of fulfillment that are tricky, he argued; the audience is still there. "If you look at historical sales for Rock Band 3, there are still millions of people who bought that game, and there are hundreds of thousands of people still playing that game," said Sussman. "The logistics of a game like Rock Band, or any game that ships with products that need to be shipped a great distance, [are] very expensive to manage. They're really complicated. And if you get them wrong, a lot of people lose a lot of money," he continued. Harmonix will be opening up pre-orders much earlier than most games, partly in an attempt to get a feel for the size of the market. They won't have to ship as many instruments because so many already exist in the wild. The audience is likely still there, and it's starved for a good rhythm game. Now the challenge is to fulfill that need without overshooting how much product should be created and shipped. Managing supply and demand is a big part of what will make or break Rock Band 4, but the team is confident. "We are a little smarter and wiser than we were 10 years ago," Sussman said. "We understand the business better."