Mac Pro’s cooling system uses randomization, draws inspiration from automobile tire design

Three fans move air through Mac Pro, keeping the system cool.
Three fans move air through Mac Pro, keeping the system cool.

Apple’s Senior Director of Product Design, Chris Ligtenberg, led the team that designed the all-new Mac Pro’s fan system.

Alexander George for Popular Mechanics:

Most high-grade PCs and displays cool things off with big fans or pump-driven water systems. But if you’ve used a Mac in the past decade, near-silent operation is a non-negotiable requirement for Apple laptops. That means Apple engineers have to find creative ways to exploit the laws of thermodynamics.

Among those engineers is Chris Ligtenberg, Senior Director of Product Design… Ligtenberg’s group built the Pro’s fan system—three axial fans in the front, with a blower in the back. Since most off-the-shelf fans would be too loud, Apple designs them internally. “Years ago, we started redistributing the blades,” he says. “They’re still dynamically balanced, but they’re actually randomized in terms of their BPF [blade pass frequency]. So you don’t get huge harmonics that tend to be super annoying.”

Noise is a major factor in the design of modern machinery. In this case: “That [solution is] borrowed almost entirely from automobile tires,” Ligtenberg says. “There’s a bit of math behind it, but you can create broadband noise instead of total noise with that technique.”

MacDailyNews Take: George also writes, “For all except a small customer base — most of them in the business of making movies based on comic books — the Mac Pro is overkill. Few need between $5,999 and $52,599 worth of computing power. But Apple is a company known for overkill design that goes on to set industry standards. Same as tech that first showed up in race cars, like rear-view mirrors and ABS, we’ll be watching for ways that the Pro sets standards for the future of consumer hardware.”

Exactly. In fact, that sounds very familiar:

Of the new Mac Pro, every Mac user should be proud.

The Mac Pro is sort of like why you fund a space program, if you’re smart. Yes, there are pressing needs elsewhere (and, btw, there always will be; it’s a bad excuse for not investing in exploration), but if you’re not pushing, you’re stagnating. Nothing unexpected can be discovered, no new solutions uncovered when no new challenges are ventured. It’s why smart car companies make esoteric supercars of which only a few will ever be sold and on which the investment will never be recouped. As with supercars, lessons learned from the Mac Pro, the Mac flagship, will percolate throughout and improve all of Apple’s product lines. Yes, Apple worst-selling Mac is their most important.

May the Mac Pro never be dead-ended, abandoned, and ignored again!

Think about what you thought of Apple’s Mac lineup when it had a half-decade-old, neglected, dead-end design as its flagship. The entire Mac lineup was diminished. Apple’s management who allowed this to happen were diminished, too. People could only see the flaws – in the machines and the people. Now, with the new Mac Pro proudly raising the flag high atop the mountain, all Macs, and everyone responsible for making Macs, are lifted up along with it. — MacDailyNews, June 6, 2019


  1. This is what happens when marketing departments write tech articles. Hyperbolic claims seasoned with a few buzz words. Yes, the engineers were so “obsessed” with efficient cooling of the Mac Pro they apparently forgot to add a simple dust filter at the intakes — something commonly found in pro/industrial products.

  2. I am still pleased with my 2010 maxed-out MacPro as well as my 2020 brand new 16″ MacBook Pro with 4 TB of SSD which I just got delivered from Santa Claus. So I will never buy the new MacPro. But I am extremely pleased that Apple now has such a beast, finally. There will be users who gladly pay 60,000 Euros (German max. price) to get such a machine as they need the ultimate power. And it shows that Apple is still inventing. Very, very good.

  3. there is NOTHING new in this machine. Its all old Technology in a shiny package. NOTHING NEW. in fact most of it is already OBSOLETE. why are they releasing PCI 3.0 in 2020? oh right, failing intel.. thats why…

    1. @ DOA:

      Your post has merit, but it’s too early to see what Apple is doing here. Let’s hang tight a while longer.

      It’s obvious that the beancounters at Apple were slow to recognize how truly horrible a value the trashcan was, and when they finally got the message, the company was swimming in so much cash that it decided to turn its designers loose to create a new cheese grater, which some of them obviously took very literally. That’s unfortunate but I doubt that the engineering of the Mac Pro suffered in the process. Apple engineers aren’t incompetent, they certainly weighed the benefits of every component spec. Let’s not pretend that HP and Dell have PCIe 4.0 systems shipping en masse either. It’s better to have a system with no weak points than a system with one shining spec and major compromises everywhere else.

      I assume that Apple’s focus on media creation now has been instrumental in driving the new Mac Pro to be a made-for-Hollywood machine initially. Who knows what media companies asked for? Probably an early shipping date rather than PCIe 4.0. Apple knows they almost lost the market, waiting any longer for a new Mac Pro would potentially kill the platform. As it is, the design seems to satisfy video pros. So cash flow being Timmy’s most important measure, of course getting the factory started for at least a couple years was the decision. Apple may slow-walk PCIe 4.0 adoption just like they slow-walked the Lightning connector (it took several years to appear on all iOS devices), USB-C on all devices (only iPads and Macs, the Trashcan never got it), Bluetooth 5, larger laptop batteries, and so on. Timmy is all about slooooooowwwww and cautious decisions inbetween social engagements. That’s what Apple is now. Slow to launch new products, slow to fix mistakes, slow to harmonize features across product lines. Super slow on the straights and event slower in the curves. It took Jobs one year to realize the Cube was bad value that customers didn’t appreciate. It took Cook 4+ years to admit the same EXACT mistake was made with the Trashcan. Too bad the lesson wasn’t learned the first time around. It took Jobs no time to realize that matching displays were a great match for MacBooks. Timmy still hasn’t decided if Apple can add more value to the user than them being forced to buy a cheap plastic display + external Facebook camera + 3rd party dock + adapter cables. Gosh, thanks for the design leadership, Apple!

      It remains to be seen if, like the trashcan, Apple will then ignore its new Mac Pro for 6 years. Much-frustrated Mac users are hoping that with a decent upgradeable platform to work with, Apple will keep offering new updates and new value. Schiller hints that they might be smarter this time around. I hope his ass will be held to the fire this time.

      Sad reality about PCIe 3.0 versus 4.0: there just aren’t many SSDs or software that takes advantage of the theoretical bandwidth advantage that 4.0 can offer. That will probably start to change by the end of 2020, at which time Apple and Intel should be prepared to announce model updates. I will be disappointed if they don’t. I am not disappointed about sticking with PCIe 3.0 today.

      If Apple was smart, it would keep the shiny new billet alyoooooominyum and chromyum Mac Pro at the bleeding edge with the latest chips every year. That would allow Apple to build a colorful plastic tower with last years’ components at mainstream pricing. That would significantly extend the product runs of the most expensive components, and Apple would reclaim some marketshare from photo professionals and the like that Apple ungraciously kicked to the kerb with poor design in the past.

  4. Hurrah for having a real Mac Pro again.

    Next, can we please have a regular Mac tower?

    In the real world outside animation studios and particle physics labs, millions of buyers have been waiting for 6 years for an affordable tower from Apple that delivers ability for users to have their own multi-display setups, the latest i7 and i9 chipsets, user repairability and future expansion with RAM and PCI slots inside the slim tower . Ability to add better graphics cards and newer ports when invariably they become available. Stuff that a sealed, thermally constrained iMac or Mini or almost as bad, a Schiller Ass Trashcan can never offer: user friendly future proofing!

    This market didn’t ask for milled aluminum billet faceplates, chrome handles, “Acceleration Engines”, Xeon processors, or terabytes of RAM. They want a Mac that would reasonably replace the much beloved Powermacs, G3, G4, G5, and Mac Pro that Apple always offered up until 2012 when Cook and his idiot Mac product managers blew it. They think the iMac addressed the mainstream market. They are wrong. Despite MS fumbling repeatedly, MS won more market share since 2011 while Cook fiddled. Apple has given away the mainstream desktop market and the stats show it. All-in-ones and sealed minis are not a winning formula. Nor do laptops replace desktops. Neither are $6k+ workstations going to attract mainstream customers. Just like the trashcan, after pent-up demand crests, Apple will have another overpriced Mac Pro with a miniscule audience. Is that the Apple plan, to start massive Mac Pro discounts in 3 years for the few remaining people who haven’t permanently moved to Windows? If Apple doesn’t want to have to deal with the complexity of serving price-sensitive customers, the downward spiral of Mac platform vibrancy won’t slow down. Mainstream Mac Apps will continue to be poor ports of Microsoft apps with weak support. You know it and I know it.

    While you’re at it Apple, how about a non-reference display for the 95% of desktop users who actually need more screen real estate than a laptop or even a single iMac can provide. To MacBook owners especially, there was huge value in having a matching display with excellent Facetime camera and docking features. Why have you abandoned your Mac users?

    This is an example of a “clean” kludged Apple centric desk. Sorry about the need for breakout boxes and mismatched displays. Want to plug in an accessory to the back of the iMac? Real handy, that. This has become the new Apple normal for everyone with less than $6k in their pockets. Crispr cider not included. Why are we supposed to be impressed with Apple design again?

    1. Superb post but I doubt many of the Apple robots will accept its facts. The real reason I believe Apple doesn’t release a mainstream product is then their horrendously inflated pricing will be more clearly comparable and evident. If your product is “odd” its harder to cross compare. Apple products are designed mainly for emotionally week people who buy based on their emotions. Apple buyers are the most ignorant in the industry. They have no idea why they are buying something except that “they want it”. Its the most blatant example of mindless consumerism we have today.

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