In my 15 years as a studio owner (Sharkbite Studios, Oakland, CA), there is nothing I've dreaded more than operating system and Pro Tools software upgrades. This has become even truer over time, as both macOS and Pro Tools have become mature platforms with newer software versions that aren't offering as many technological leaps forward. Sonically (and functionally) I could have happily remained on Pro Tools 10 for years to come, though admittedly I'd be missing out on some snazzy new editing features. What started really nagging at me were the limitations of an aging operating system, in terms of compatibility in the audio realm (the latest plug-ins) and issues with basic computing tasks, like outdated internet browsers being unable to use file transfer sites. With more Pro Tools 12 sessions coming into the studio from our clients, dealing with an upgrade seemed to be unavoidable.

The Sonnet xMac mini Server is a 1U rack mount enclosure that houses a Thunderbolt equipped Apple Mac mini, plus two PCIe 2.0 cards. I had been running Pro Tools 10 natively on a Mac mini in my old mix room for the last few years, and had always marveled at what a little powerhouse that thing was. When I'd heard about the xMac mini Server, I really wanted to give it a shot. Being able to use a Mac I already had on hand lowered the price point to enter Pro Tools' "HDX-land." I also loved the idea of having the computer and PCIe expansion chassis mounted in one slick-looking rack-mounted unit, replacing the big Mac Pro that was lurking next to the rack.

The xMac mini Server arrived well-packed. It's a big, solid hunk of metal, and at 17.72 inches was deeper than I had imagined. Those of you with shallow racks will want to confirm your dimensions before purchasing. With the top popped off, it was clearly laid out and every needed cable was thoughtfully included, and neatly arranged, to interface the Mac mini with the Server's front and rear panels. After assembly, I plugged the unit in and yowza – the rack's PSU fan was loud! Smaller fans have to spin faster, and thus create more noise – an obvious trade-off for the size of this rack. I powered up the Mac mini, and as its set of fans started up my heart sank. This fan noise was going to be too loud for placement in our control room. I started poking around on the web and it turns out Sonnet sells an "extra quiet fan module." After consulting with the nice folks at Sonnet, they sent the quieter version of the fans my way, and installing was a cinch.

We mounted the xMac mini chassis into our rack, integrating it with our two Lynx Studio Technology Aurora 16 interfaces [Tape Op #73]. After all required software was loaded onto the Mac, I started a #large mix session in Pro Tools 12 for testing. There were at least 50 tracks in the session with many native and UAD plug-ins. The system didn't flinch when I armed 32 tracks. Sweet! Some fan noise still prevailed, but I decided to hold off final judgment until our other studio regulars had a chance to use the xMac mini Server rig.

Sharkbite regular, and Tape Op contributor, Scott Evans <antisleep.com> spent time with the xMac mini: "I've done a few tracking sessions at Sharkbite with this new rig, and barely noticed the change from the old Mac Pro. It still feels like using a Mac with Pro Tools HDX. There's a bit of fan noise, but not enough for me to flip out about – it's probably quieter than my two Avid interfaces at my place. I love my 2012 Mac Pro, but it's not young, and Apple has obviously lost the plot with ‘pro' hardware. If I had to buy a Mac for my studio tomorrow, I would seriously consider a xMac mini Server/Mac mini combination."

Matt Boudreau <workingclassaudio.com> often tracks at Sharkbite, and he shared his sentiments on the xMac mini Server, echoing Scott Evans' opinions: "It performed like I would expect a Pro Tools HDX rig to perform in a commercial studio environment. A couple of hours into the session I did notice the fan noise, but it wasn't a deal breaker or show stopper for me. My biggest wish list item would be to have multiple USB ports on the front of the unit. I showed up to the studio with two drives and discovered that the only secondary slot was located in the back of the unit, which was racked and difficult to get to. An external USB hub could easily conquer this hurdle. Unfortunately new Macs don't offer built-in PCIe slots that could accommodate Pro Tools HDX cards, and based on Apple's record I wouldn't hold my breath. The xMac mini Server/Mac mini pairing is not only a viable option, but it's also priced well for the average studio or engineer."

Tape Op's Scott McChane is also a regular engineer at Sharkbite: "I used the xMac mini Server extensively for six weeks in tracking, editing, and mixing scenarios. During live tracking and dense editing, the enclosure and its little Mac mini counterpart never let me down. With the mini's SD system drive, and the upgrade from Pro Tools HD 10 to HD 12, I felt the performance improved versus our older Mac Pro tower setup – and newer versions of Pro Tools (starting with v11) offer Avid's 64-bit floating point mixer, which is all the difference in the world to my ears. We have one HDX card at Sharkbite. I'm stoked that there's an option to add another HDX card later, or maybe a UAD-2 Accelerator card. A cool ‘geeky' feature is Sonnet's ThunderLok retainer clip for the mini's Thunderbolt cable, which prevents unintentionally unplugging the cable while rooting around near the back of the rack. Optical Thunderbolt cables (up to 30 meters) are available that could allow the xMac mini Server chassis to run from a machine room, or closet, outside the control room. Sonnet also offers smaller desktop Thunderbolt/PCIe enclosures that may be more appropriate for editing suites and project studios."

Functionally, the xMac mini Server enclosure has been darn solid. No one has been bothered by the fan noise, and sessions have been flawless. There is a known issue with wi-fi reception (due to the Sonnet's formidable chassis), but this can be addressed by running an Ethernet cable from your router direct to the chassis. All in all, I have been very pleased with my first foray into the world of external chassis, and how seamlessly the xMac mini Server has integrated into my studio.

Tape Op is a bi-monthly magazine devoted to the art of record making.

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