Universal Audio: Apollo x8p Thunderbolt 3 Interface

Universal Audio – knock it off, already. We could probably end this review right there, and most existing Universal Audio/UAD users would get the point: the release cycle from this company is nothing if not consistent in its ability to disengage one's better judgment from, ahem, sympathetic management of one's wallet. The latest trio of Apollo X generation interfaces is no exception to this principle. The Apollo range, initially taking flight in (what seems like prehistoric) 2012, has made a considerable impression in professional and project studios across the globe, leading the industry with a price-to-performance ratio that is unparalleled.

Although other manufacturers have, on occasion, inched ahead of Universal Audio in the spec space race, the Apollo Xs have come roaring back, with dynamic range figures that are stellar at this (or any) price point – Apollo x8p boasts 129 dB of dynamic range, with signal-to-noise spec'd at -119 dB THD+N. Specs are specs, of course, but add up all of the additional features and refinements made to this third generation of Apollos, and you have a pretty compelling reason to, I don't know, skip a mortgage payment or two in favor of a studio upgrade.

Let's start with the I/O – of the four available new X-flavors of rack-mount Apollos, we're looking at the x8p variant, which is a direct replacement for the previous-generation 8p [Tape Op #111]. Like the 8p, this particular rocket ship veers towards live tracking, with eight XLR combo jacks, two front panel Hi-Z TS inputs, and TRS monitor outputs. Like the 8p, the x8p also features four ADAT (S/MUX) optical ports (two in and two out). The first significant physical change to the back panel is the presence of two DB25 connectors – one each for line outputs 1-8 and line inputs 1-8. The older 8p combined the line and mic inputs on one combo jack per input (although perhaps not patchbay friendly, that is still an option for the x8p if desired). The 8p also sported the eight line outputs on TRS jacks, two of which were dedicated to the monitor path. In contrast, the addition of the DB25 patch points on the new x8p is a welcome sight and makes it so much easier to wire up to my D-sub patchbays.

The new Apollos are now Thunderbolt 3 enabled, which is again a welcome sight for anyone who has purchased a computer over the last few years – as Thunderbolt 2 has been retired (primarily on Mac hardware) in favor of Thunderbolt 3. Thunderbolt 3 has twice the throughput of Thunderbolt 2, and (on the Apple side of the fence at least) is backward-compatible with Thunderbolt 2 devices (provided you have Apple's ridiculously pricy adapter dongle or a compatible dock). I tested the x8p with a 2017 MacBook Pro and a TS3 Plus Thunderbolt 3 dock from CalDigit. I attached my Apollo Twin MkII [Tape Op #121] directly to the second Thunderbolt 3 port on the x8p via the Apple Thunderbolt 2-to-3 adapter as mentioned above – everything was immediately recognized by the Console app, and I was on my way to the requisite out-of-the-box firmware upgrade, which was applied with nary a hiccup. Using this setup (with other USB peripherals attached to the dock) keeps my studio desktop Marie Kondo-approved – I have a single Thunderbolt 3 cable to plug into my Mac which provides instant, full-throughput, low-latency connections to the interfaces and other studio knick-knacks all while providing power to the laptop. Huzzah!

One of the flagship features in the new Apollos is the upgrade in DSP via the inclusion of six cores ("HEXA Core") – all flavors of Apollo now come with this bump in processing power. This is significant for users who have invested in the UAD platform, and especially useful for the x8p in that I can now instantiate even the most processing-intensive Unison plug-ins across all eight preamp slots. Real-time zero-latency 96 kHz tracking through eight Neve 1073s or 88RS channel strips, with Pultec EQs and Empirical Labs Distressor [Tape Op #126] plug-ins scattered throughout? Thus far, it seems this single rack unit can do all the heavy lifting. Paired with my Twin MkII Quad-core, however, I now have a crap-ton of available processing headroom when mixing – I have yet to see the dreaded "DSP load limit exceeded" message. Give me time, of course, and it'll happen for sure – but it's nice to have the extra horsepower available. As the UAD platform continues to develop for Analog Devices' SHARC silicon, it'll be interesting to see the evolution. Eight and twelve core Apollos are surely certain future releases, but will Universal Audio move to a different, potentially more efficient chipset in the years to come? And how will that affect their existing userbase?

Speaking of under-the-hood improvements, Apollo X units now use two discrete crystals for clocking (as opposed to a single in the previous generation). One clock does the math for 44.1 kHz and multiples (88.2, 176.4), and the other for 48 kHz and multiples (96, 192). Everything in the conversion path starts with stable clocking, and jitter across the entire Apollo X family is less than 10 picoseconds – so yeah, this is premium rocket fuel in the tank.

There are many smaller, but significant workflow improvements implemented throughout, including a built-in front panel talkback mic. Similar to the Twin MkII, the mic is also available in the UAD Console app as an input, which is a neat trick. The addition of 7.1 surround monitoring support is cool. While it future-proofs my control room to some degree, I'm not currently mixing in 7.1 and thus couldn't test it. But I was happy to see that UA's Console app now includes some basic speaker calibration features (even for "old-fashioned" vanilla stereo monitoring) – you can now swing your monitors left/right in 0.1 dB increments if needed. It would be interesting and helpful to see Universal Audio wedge something similar to Fuzz Measure [Tape Op #118] or Sonarworks Reference 4 into its Console app for basic acoustic/frequency response measurement, or even DSP-based room calibration.

Back to the nerdy details: the Apollo X line now offers switchable headroom for the line inputs, line outputs, and monitor outputs (from +20 dBu to +24 dBu) – so, for instance, tape transfers and interfacing with analog outboard can be managed at the appropriate levels. Fairly often, I do like to process DAW tracks with a couple of different 8-track machines (I've grown pretty fond of the sound of a particular ‘80s' Tascam cassette 8-track) and found that having this additional 4 dB of output headroom on the line outs to be very useful. One interesting consequence of bumping your headroom up is that when recording new tracks with +24 dBu headroom through the Console app (in a session previously created at +20 dBu), you will need to add increased gain to the UAD plug-ins in order to get them to sound the same as UAD plug-ins allow for analog-style gain structures (and all the non-linear analog-like behaviors which come with gain staging).

Speaking of gain staging, another nice little workflow improvement to the front panel of the Apollo x8p are the Gain Stage Mode indicators – when in Gain Stage Mode, you can quickly see which of the two or three gain parameters you're tweaking with an indicator to the left of the monitor levels (U1, U2, U3).

Although I have yet to record and mix with an Apollo that sounds "bad," the AD/DA conversion has improved yet again with the X line, and I can say with Professional Certainty(TM) that my ears are happy, and my clients' ears are happy too. In fact, I've been tracking an upcoming solo EP for Greg Brown (CAKE/Deathray) who has always been skeptical of digital recording. At day two with the x8p, when he remarked on how good it sounds and how it has been the closest in feel to an analog workflow (and resulting sound) that he has yet experienced, I knew my wallet was in trouble. TL;DR – just take my damn money, again.