The sound of the mouse is wrong. The desktop is the soul of Apple.

The iMac may be a truck, but Apple is making sure it comes with all the bells and whistles of a race car. Earlier this year, the top-secret lab that designs Apple's Mac accessories was beset with a foot crisis. The problem was a mouse that ships with the new iMac. Called the MaGIC Mouse 2, the input device looks identical to its predecessor. But its internals are very different, largely because Apple has swapped out the alkaline batteries in the mouse for rechargeable lithium batteries.

Everything seemed to be going well in the process. The built-in lithium battery was custom designed to fit the mouse's internal slot. The antenna, which was redesigned to prevent interference from the battery, also worked well.

But there is one thing that is totally unacceptable.

The sound of the mouse working is not right.

Kate Bergeron

That's what Apple chief engineers Kate Bergeron and John Ternus told me when I was the first journalist to visit the Input Device Design Lab. As usual, the updated iMac has many new features to shock existing Apple users, frustrated Windows users, and hesitant new customers. The most obvious is the application of Retina screens across the product line: there are smaller sizes available, namely the 21.5-inch model with 4K Retina display, and the most advanced 27-inch model with 5K display. The display also uses new technology, with a much higher color gamut than before, and the details of photos and text display are extraordinary.

Another big advance is the new iMac trio: a wireless keyboard, trackpad, and mouse. Unlike previous Bluetooth versions, these wireless input devices ditch the replaceable batteries and instead use rechargeable lithium batteries like the iPhone and iPad, which charge via the "lightning" port. The Magic Trackpad 2 also integrates the Force Touch feature first used on the Apple Watch and now also used in the MacBook and iPhone 6s. (Force Touch is a touch-sensing technology that allows the device to sense the force of light and heavy pressure and use software to call up different corresponding functions.)

The new iMac is priced the same as the previous model, and has improved processors and graphics cards. Like other Apple products, Apple's attention to detail is almost fanatical.

The mouse sound problem has caused employees in the office to feel uneasy and confused. Apple's input device design lab is located in Vallco Parkway, a few miles away from Apple headquarters. Behind the door is a series of unusual machines that are rarely visited by outsiders. They are used to measure and test the latest Apple hardware and solve problems with products.

The culprit appears to be the polycarbonate feet on the bottom of the mouse. "We changed the structure of the bottom feet, which also affects the friction sound," said Bergeron, Apple's vice president of ecosystem products and technologies.

“We spent a lot of time designing our previous mice on those feet, the materials, the assembly structure, so the mouse sounded and felt great on the desk,” said Ternus, vice president of Mac and iPad ecosystem and audio engineering. “But now the product has been greatly improved, and all of a sudden the feet we loved don’t work on the new product. It’s not what we want anymore.”

We want to know, what went wrong?

"The sound of the mouse has changed," said Ternus, who has worked at Apple since 2001. "The problem is that we need a sound that everyone likes, and the current one doesn't sound right."

"Yeah, that's not right," said Bergeron, who has been with the Mac team since 2002. "You just don't like the sound of it."

John Ternus

There are many reasons why Apple is the most valuable company in the world. Tim Cook is known as the master of the supply chain, and he internalized the focus on innovation that was instilled in the culture by his predecessors. Jony Ive is admired around the world for turning Apple into a benchmark for design. Apple's marketing and branding strategies also set the standard for the industry. The labs of Apple's legendary desktop computer are also one of the reasons for its success.

Strict attention to detail.

A slightly imperfect sound isn't a product killer, or even an official bug, but Apple engineers were determined to make the Magic Mouse 2 for the new iMac make a better sound when it slides across the desktop.

Of course, the bigger question about the iMac remains: Why care so much about desktop computers? After all, a month earlier, Apple CEO Tim Cook had declared, while showing off a new large iPad Pro and keyboard, that "iPad is the clearest representation of the future of personal computing." Does that mean the iMac will be a thing of the past? Steve Jobs foreshadowed this question in 2010. "Personal computers will be like trucks," he said at the D conference in May of that year. In the mobile age, is even the new iMac just a boring computing machine?

Phil Schiler, Apple's senior vice president of worldwide product marketing, said: "It's not that simple. We are in an amazing era where different products are competing to enter people's lives. It's great, I love this world. What kind of products to provide to customers is a question we have been thinking about carefully. The first is iPad. It can basically do what you want to do on a personal computer. Many people regard iPad as their first computing device, and it deserves it. This is even more obvious in iPad Pro. But this is not for everyone. There are still people who think that these can't meet their needs in life, including Mac."

Phil Schiler

In fact, Schiler has a philosophy about Apple's product line: Ideally, you should accomplish as many tasks as possible with the smallest device before moving on to the next generation of the product line.

"They're all computers," he said. "Each device is unique and timeless. The function of a watch is to get things done on your wrist so you don't have to pull out your phone as often. The function of a phone is to do more things, maybe replace the iPad. The function of an iPad is to be powerful enough that people don't need a laptop anymore. Like, why do I need a laptop? I can just add a keyboard and use my iPad and do everything! The function of a laptop is to get you to get rid of your desktop, right? We've been working on this goal for a decade, and the poor desktop is left at the end of the product line. So what is its function?"

Good question! What’s the answer?

"Its mission is to challenge our traditional perception of desktops and make possible things that desktops couldn't do before," Schiler said. "The functionality and performance are getting stronger and stronger, and that's why we need desktops. If all the desktops do is to compete with laptops and become thinner and lighter, then there is no need for this."

Which brings us back to the new iMac line. Even as Apple’s revenue and profits are dominated by the iPhone, Apple still considers the Mac an important business. The iMac is even more revolutionary, according to Schiler. (Apple doesn’t break out iMac sales, with Macs selling at nearly 5 million per quarter. But iPhones outsell Macs by a factor of 10.) “We’re very serious about the Mac,” says Brian Croll, vice president of Mac product marketing, who joined Apple in 2001.

Its importance goes beyond those sales figures: The iMac will inevitably go down in history as a crucial product in the renaissance that followed the return of Apple’s co-founder. It’s no accident that the new movie “Steve Jobs” ends with the unveiling of the first iMac. Although the film’s editor, Aaron Sorkin, takes liberties with the iMac, there’s no denying that the iMac is a symbol of Apple and its subsequent renaissance. During the days I spent with Jobs during the unveiling, he made it clear that it was absolutely necessary to build a great desktop computer for consumers. “It’s our soul,” he told me.

In a sense, the iMac’s eye-popping Retina display is a continuation of that tradition. “The display is the stage for the software,” Steve Jobs told me when the original iMac was released. With the new model, Apple has created a stage big enough for The Lion King.

Of course, it was inevitable that Retina displays would appear across the iMac line when the technology debuted on the iPhone in 2010. It made its way to the Macbook in 2012, then to the iPad and even the Apple Watch. "We really, really wanted to put Retina displays on the iMac," Ternus said. "The iMac was crying out for it."

Tom Boger, Apple's senior director of Mac hardware, explained to me that the iMac's display incorporates not only a higher screen resolution, but also a larger color palette that requires new technology to support. Even compared to the current $2,500 iMac Retina display, the new generation is an improvement. "We gave it a wider color gamut," he said. "That basically means they have a larger palette of colors to display." All high-end monitors aspire to display all the colors visible to the human eye, which is a huge technical challenge. The old industry standard, called sRGB (standard red, green, and blue), does a good job of capturing most of the color spectrum. Today, Apple's Retina display is 100 percent sRGB. "We're very proud of that—a lot of monitors don't even meet 100 percent sRGB. So that's really great," Boger said. "But about 10 years ago, the film industry got together and said they could do better, and they said there were more colors in the world that we could show in movies. So they created a new color standard called P3. It's actually 25 percent larger than sRGB." By supporting P3, the new iMac can display richer colors.

"Color is so important, but we didn't have the ability to solve it before," Ternus said. Apple had proposed a solution that involved a new way to code LEDs (light-emitting diodes) that would filter the high-intensity red and green light produced by the LEDs through a color filter to generate the entire color spectrum. The team then had to find suppliers who could make this solution a reality. One option was a technology called quantum dots, but Apple rejected the proposal because it would use the toxic element cadmium. "Ultimately, we found this path with our LED supplier that met all of our requirements without the environmental downside."

One question is how much of a shift it will make for us regular users. In Apple's image A/B testing, I could definitely see some difference, not just in color rendering but also in the extra detail that the expanded palette showed. But don't expect to see a dramatic difference in your iPhone photos: The P3 effect only really explodes in high-pixel images like DSLR RAW data and other high-resolution images. Movies are another matter; you can't currently download 4K UHD movies from the iTunes store. Apple acknowledges that P3 is really for the pro market.

“Professionals are really obsessed with the palette and they’re buying it,” Croll said. “Consumers see it and say, ‘Oh, black, I don’t understand why, but it looks better,’ ”

One thing that's noticeably absent from the new iMac, however, is a touchscreen. While Microsoft and others now believe that multitouch should be extended to desktop displays, Apple sees it as a dead end. "We've looked deeply into this from an ergonomic perspective, and we think that it's uncomfortable to get up and use a touch interface on a desktop with a keyboard attached," Schiller said. "iOS was designed from the ground up to be multitouch - there's none of that mouse-driven stuff in it: a cursor that moves around, or a tiny 'close' box that's so tiny you can't hit it with your finger. Mac OS was designed from day one to be an indirect pointing mechanism. The goals of these two worlds are different, and that's a good thing - we can optimize for the best of each world instead of meshing them into a 'lowest common denominator' experience."

(Speaking of Microsoft, Schiller said that although he had not tried it, he had read about the new products Microsoft released last week and applauded them with amazement. He emphasized that Microsoft's full entry into computer hardware was a tacit acknowledgment that Apple was always right about this. "It's great that an event has so effectively verified Apple's approach and held us up as a benchmark. It's a compliment to us.")

Apple is still committed to multitouch across its product lines—it just thinks that on the desktop, touch should be a simple, easy experience. Apple has been methodically bringing multitouch gestures from its mobile operating systems to desktop add-ons like the Magic Mouse and Magic Trackpad. But this iMac refresh may be best remembered for new input devices with built-in rechargeable batteries. "We were driven by environmental considerations," Schiller said, meaning that Apple's toxic footprint could be significantly reduced by moving away from AA batteries. A two-hour charge gives more than a month of use. But even if you forget to charge, a minute of plugging the input device into a USB port on your computer will give you most of a day's use. And for those who previously struggled to establish a Bluetooth connection, it'll be nice to know that the mouse or keyboard pairs instantly when you plug it into your Mac.

But putting the battery inside the device forced the Mac team to do some pretty big redesigns. Until now, standard wireless keyboards and trackpads have featured a small support roller with the battery on top. This dictates the entire user experience, creating what Apple calls the "springboard" effect.

For the keyboard, removing the battery compartment means Apple can actually make the whole device smaller while still making the keys larger. "We've been working hard to improve our input technology for a long time, and earlier this year, we finally achieved a breakthrough, as we saw in the MacBook, where precision in keys and typing is something we really want to get right," Bergeron said.

While the Magic Keyboard's keycaps are larger than its predecessor, Bergeron revealed that a prototype had even larger keycaps. "We did a lot of development early on and probably went a little bit more extreme than we needed to, so we backed off a little bit." The result, she said, is minimalism. "We made the keyboard as full of keys as possible, minimized the edge area, and made the keyboard take up as little space as possible on the desktop. It's lighter than the previous version, but just as stiff."

The Magic Trackpad 2's redesign is almost revolutionary. Its surface area is 29 percent larger than its predecessor, wide enough to accommodate the frequent swipes that have been brought into the Macintosh experience from the multitouch world of iOS. "The whole touch experience demanded that the trackpad be larger," Croll says. "Our philosophy is that [the iMac] is a crazy multitouch device—when you put your hands down." Because it lays flat, users can get the same result with the same amount of force no matter where they click. It's made of high-performance glass, so it can withstand a knock or a fall. And, perhaps most importantly, the trackpad now supports pressure-sensitive touch—another step toward the unstoppable convergence of desktop and mobile experiences. In fact, porting pressure-sensitive touch to the desktop clarifies Schiller's vision for how features will permeate across Apple's product lines. Remember, Apple first applied this idea to the iWatch, moved it to the iPhone this year, and now to the iMac. "We've really been joining forces," Croll says. "The same people who developed iOS are the same people who developed OSX. They have both models in their heads."

The iMac might be a truck, but Apple is making sure it comes with all the bells and whistles of a race car.

My trip to the Input Design Lab dispelled some of the confusion about how Apple plans to iterate across its product lines. While Apple appears to have a strict schedule—and a cottage industry is devoted to creating unofficial calendars for product releases—company executives adhere to the Orson Welles principle of never releasing until it’s time. In the case of the new iMac, the new features came from a confluence of factors: the always-inevitable feasibility of a Retina display; the need to introduce pressure-sensitive touch to desktops; the environmental push to move away from disposable batteries; and the cheaper chips and components made possible by Moore’s Law. (Another benefit I didn’t mention: Fusion storage, which combines the large capacity of hard drives with the fast access of flash memory, is now much cheaper.)

In addition, once the deadline is set, the development team must focus on getting the product out of the lab and into the market. In the case of the mouse, the developers found that the button sound was not right, which meant they needed to find a 'harmonious' solution.

Luckily, Apple has a ton of machines at its Vallco Parkway lab that can help with these issues. For example, there's a machine dedicated to testing mice on a variety of surfaces, measuring friction. Another machine setup involves putting a mouse or typewriter keyboard in a soundproof (super soundproof) environment to take very precise measurements of where exactly the noise is coming from. In the case of the 'not right sound', it's the way the new mouse's slider contacts the sliding surface. The original Magic Mouse maximized the contact area with the sliding surface. But that design doesn't work with the new Magic Mouse. "It's a little bit sticky - not to the point of not being able to glide, but it's definitely not the perfect glide we want across the desk," Bergeron said. That's what causes that 'not right' noise.

"The solution was to redesign the HDPE slider. This time we moved the slider further to the edge of the mouse and got a better feel," Bergeron said. "It turns out that geometry was the variable that made the difference." After creating several sliders with different designs, the team held a draft to choose the best one. Ternus explained that the selection process "was to bring together a core group of people from the engineering and design teams, look at different samples, and when they all said, 'Yeah, that's it, that sounds great!', we went with that one."

Then, the same process repeats itself. "Even after all these years with the Mac, there's still a lot of things to do," Croll says. "It's like a roller coaster, one ride after another, over and over again. There's so much to do." As you might expect, work on the next iMac has already begun.

They didn't show me that one, though.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.