Apple completely redesigned the iMac this year and it's the first time in nearly a decade that the iMac has looked drastically different. The 2021 iMacs are thinner, lighter and, also for the first time in decades, they come in colors like red, blue, yellow and green. Each iMac has a bigger display, thinner bezels, a smaller base stand and a new-look power cable. Apple decked each model out with improved speakers, mics and a 1080p webcam. And, for the first time in an iMac, it finally supports Touch ID.

Of course, the catalyst for the redesign was the integration of the M1 chip which has enabled Apple to drastically reduce the size of a lot of key components, like thermal and cooling system, without compromising performance. In fact, the 2021 iMacs promise to be significantly better machines, despite their thinner and lighter design.

Ahead of the officially release of the 2021 iMacs — available for preorder now, and shipping on May 21st — we had a conversation with Kate Bergeron, Apple's VP of Hardware Engineering, and Tom Boger, Apple's VP of Mac and iPad Product Marketing, who explained how the M1 chip has allowed them to completely redesign the new iMac.

24- inch iMac

The following interview has been slightly edited for clarity and brevity.

How did the M1 chip allow you to redesign the iMac?

Tom Boger (TB): In the new iMac, it's the first time where we are able to design a product from the ground up knowing we were going to put the M1 chip in it and take advantage of all that entails. So that allowed us to look at everything about the design. The cooling system, the enclosure itself, and it wasn't just the power efficiency of M1 that influenced the design, but the technologies that M1 has, like its really advanced ISP (image signal processing) for the camera. So it really influenced everything about the new iMac design.

Kate Bergeron (KB): I think one of things that you mentioned on the power and efficiency side...all of the things that we considered the iMac to be before [this new iMac] required a pretty heavy lift on the thermal side, which means making big heat sinks, big heat pipes, etcetera, and for the M1 iMac we were able to put a bunch of those things aside because we didn't have to create these big thermal solutions. So being able to make the Logic Board really small and compact was really exciting for the team. The fans were so much smaller, and everything is just as efficient as it can possibly be.

TB: One of the things that people might not realize is that, at Apple, we don't do new designs for just the sake of new designs. We do new designs when we can make an appreciable advance within the design. And so we had this previous 21.5-inch iMac enclosure around for many many years. We hadn't changed it. And the reason why is that no new technology had come along to dramatically allow us to continue to make another big step in our vision of having the computer disappear.

The 21.5-inch iMac has a very power hungry CPU and it has very power hungry GPUs, and we had big thermal systems and fans and things like that, and so what's really stunning about this new iMac, and you can see the huge heatsinks and fans that we were able to eliminate and now use much more compact, is that even though we were able to do that, the performance is still really great compared to the previous 21.5-inch iMac.

The 2021 iMac has been redesigned from the ground up around its new M1 chip. It’s thinner, lighter and way more power than previous iMacs.

So, how does the new 24-inch iMac compare to the previous 21.5-inch iMac?

TB: The previous 21.5-inch iMac was a very powerful system. It had up to 6-core core i7 Intel processors and it had up Vega 20 graphics from AMD. And the combination of those two was really powerful. Now when you configured that as a customer, we're talking $2,000 and above. I'm talking the highest-end options that a customer can figure it with. That machine was very powerful. We actually designed it for certain pros that need a more compact enclosure.

When you compare this new iMac to that old iMac, the numbers that we shared from a CPU standpoint, you can see up to 85 percent faster performance than the previous 21.5-inch iMac. When you compare it to the "normal" GPU graphics that are across the mainstream part of the line, you can see up to 2x faster graphics. And then even if you choose that really high Vega 20 [graphics] option, you can see up to 50 percent faster graphics. The caveat here is that this is software that has been optimized for M1. You're not going to take an old game that hasn't been optimized and just run it, you're not going to see those kinds of leaps in performance. However, there are thousands of universal apps that have [already] been optimized for Apple silicone.

All in all, that's the magic of this. We're able to take a huge step in realizing our vision of making the computer disappear, having this stunning design that everyone would be proud to have in their home or public space. And at the same time, deliver killer performance in a system that's very quiet, and that's another thing that people love about their iMac.

How is the M1 chip able improve performance so drastically?

TB: The M1 chip not only can it run a benchmark really fast, but it [can also improve] everything you do, from web browsing to being able to have hundreds of tabs open. One of the things that it really excels at is video editing and that's a testament to its unified memory architecture.

In a traditional PC design you have the CPU with its own memory and you have the GPU with its own memory, and any time the CPU needs something that's in the GPU's memory, it has to send that data across the PCI bus, which is relatively very slow and high latency and not very high bandwidth, and it's hard to do. And where it's really pushed is in video applications because it's unrelenting and demanding. It's 60fps constantly and you're processing those frames and you're trying to add titles and overlays and data is going back and forth, and in a unified architecture, the CPU and GPU are all addressing the same data in the same memory that they all have fast and high bandwidth access to.

One of the best use cases of the unified memory architecture is video and that's why on a MacBook Air you can now do multiple streams of 4K editing. On a 13-inch Pro you can do up to 8K of video [editing]. And now on this iMac you can do multiple streams of 4K and up to 8K. The M1 architecture, not only is it fast for very specific demanding tasks, but it gives you just an overall experience that's unlike what the Mac has been before.

The new iMac comes in seven different vibrant colors: green, yellow, orange, pink, purple, blue and silver. Each models ships with a matching keyboard and mouse (or trackpad).

Was the new design influenced by the pandemic at all (i.e better webcam, speakers and mics)?

TB: Our roadmaps our years in advance. Kate and I are working on things that you can imagine are shipping two or three years from now. But it's one of those things that we are constantly. I'll put it this way: when we approach an iMac, or any of our products, it's really about the experience. So we don't want to just give a huge performance bump without looking at the entire experience. And you're right, all our customers, more and more, the quality of the cameras, speakers and mics are more important than ever. We are always trying to advance that anyway and we have a roadmap for those technologies. And it worked out that this new iMac is appearing at a time when those things are incredibly important to everyone.

And you know this isn't the first time we've had studio quality mics. We brought it out in the MacBook Pro first, and it's another testament that in our product line, some product lines inspire other product lines with new technologies like studio quality mics. And now we have the 1080p camera. It's not our first 1080p camera, but what's different about this one is that it's now paired with the ISP in the M1 chip, which does an amazing amount of processing for reducing noise, auto white balance and whole bunch of things to make you look good on the camera.

And then the speakers. Think about Apple's product lines. We do everything from big Mac Pros to little tiny AirPods and HomePods, and we have a tremendous acoustic team that is constantly pioneering our audio technologies. So we set out as one of our goals with this new iMac is to put the best speaker system we could in it, the best we've ever put in a Mac, and we feel like we've done that.

KB: I think the balance of great audio quality along with the team pushing us to make the product thinner. The team had to get really creative and we actually used the speaker enclosure on the back of the system enclosure to create a more rich bass sound.

So in a traditional implementation, such as in our prior iMacs, we had separate speaker modules that we put into the computer and screwed them down. This time, because we were trying to optimize for thinness as well as performance, we actually mount the speakers directly into the enclosure and use the backside of the enclosure as part of the speaker, which is new for us. So it gives you that really nice rich sound even though the product is thinner than what we had before.

The 2021 iMacs are the first with a wireless keyboard that supports Touch ID. Apple doesn’t not sell these wireless keyboards separately (yet), but if you were thinking of grabbing one should they become available, know that Touch ID will only work on a M1 Mac.

How has M1 chip enabled Touch ID on the iMac for the first time?

KB: We had to create an encrypted channel between the keyboard and the M1 chip wirelessly, which is different from our laptop systems that's all hardwired in. So [the new iMac] has Secure Enclave on both sides. We have our own silicone as part of the Touch ID on the keyboard and it's able to communicate with M1 wirelessly and in a secure way.

So we're really excited because customers love the Touch ID experience on their laptops and now they're able to have it on their standalone iMac. They're able to use it for Apple Pay and Touch ID for logging in.

TB: The keyboards themselves, if you use them with a non-M1-based Mac, all the aspects of it will be functional with one exception — and that's the Touch ID key. To use Touch ID on those keyboards you need a Mac with an M1 chip.

Did you know all along you were going to bring color back?

TB: The color was something that was designed in from the beginning. It's not like we made the silver version of the iMac and then said 'Oh, let's now make them in different colors.' From day one, the design team knew we were going to bring back colors to the iMac in a big way and we're going to design every single component with color in mind.

It's been many many years since we've had color like this in iMac and, again, we really wanted to get back to that original vibe of the iMac — just fun. And I think the timing is just perfect. It's been a tough year-and-a-half for everyone and finally spring has sprung and we're starting to move about more and things I think in general are more optimistic these days.