Review: PreSonus Quantum Audio/MIDI Interface - ProSoundNetwork.com
PreSonus has squeezed a whole lot of utility into one rack space, says producer/engineer/reviewer Rob Tavaglione.

Thunderbolt is where it’s at—at least in my studio, where my desktop Mac Pro “trashcan” and my MacBook Pro (for location work) both utilize this very fast, high-throughput, low-latency interconnection technology. So I was very excited to see PreSonus’ new top-of-their-line recording interface—named Quantum—that employs Thunderbolt 2 alongside new-generation microphone preamps, comprehensive control software and reportedly easy integration with Studio One, PreSonus’ all-in-one, do everything DAW.

PreSonus has squeezed a whole lot of utility into only one rack space: 24bit conversion at up to a sample rate of 192 kHz; eight channels of recallable Class-A XMAX mic preamps; two instrument DIs; 10 line-level outputs on quarter-inch TRS; two channels of SPDIF I/O; word-clock I/O; 16 channels of ADAT optical I/O; MIDI I/O; and Thunderbolt 2 (with two connections for daisy chaining more devices onto your Thunderbolt bus). There is also a built-in talkback mic, mute/dim/mono monitoring functions and two independent headphone circuits.

Quantum comes equipped with Studio One Artist, the “lite version” of PreSonus’ powerful Studio One, which allows remote control of the XMAX preamps via your computer. You are not married to use it with Studio One (or Artist) however, as UC Surface is also provided free; it allows remote mic amp control as well as an abundance of useful features (like metering and a RTA display), even if you employ a third-party DAW.

The Quantum has 60 dB of gain available at the preamps, achieves 120 dB of dynamic range and utilizes DC-coupled outputs. For the full list of features and specs, visit the Quantum page on the PreSonus website.

It’s been a long, long time since I’ve used PreSonus mic amps, so I must say that they’ve come a long, long way. On that note, the Quantum itself seemed to pack more heft and weight than I expected, with a nice solid feel overall. In particular, the external PSU connects with a typical-looking co-axial plug that actually twist-locks into place. Note to other manufacturers: PreSonus has raised the bar; up your game!

The combo input jacks and line outputs had a good firm feel in use, even though they are directly surface mounted to the PCBs. Onboard metering was reasonably visible for such small meters, although more metering is available via UC Surface. The rotary encoder is fine; it didn’t have the firmest feeling and the switches were about the same. I go into this critical detail because, frankly, I’ve had durability problems with some PreSonus gear in the past and wanted to accurately assess just how much value can be expected for the bucks. So far, I’d say that the hardware quality has definitely improved; even if it doesn’t quite match the level of hand-soldered boutique gear, it doesn’t feature the elevated price tag of such gear either.

Encouraged by success around the studio, I went ahead and took the Quantum out on a location job. It wasn’t a tough one: 44.1 kHz sample rate, only four inputs of choir overdubs for a live concert Gospel recording, and foldback of only one mono mix to a powered wedge for choir monitoring. Quantum’s mic preamps sounded great with my Neumann and Roswell LDC mics, handling the headroom demands nicely without any noticeable phantom power sag. The sound wasn’t exactly big and euphonic-like with transformer-coupled mic amps (or tube-driven models or any that strive for a bigger-than-life presentation); instead, it was more reference and uncolored, just as they should be for this product.

In order to dig in deep, I put together an entire song at 96 kHz with the Quantum, desktop project studio style. My TR-8 drum machine sounded great through the line level inputs 1 and 2, set for -10 sensitivity. A Cajon tracked well (with a ribbon and a spaced pair of Mini K47 condensers) with natural dynamics, sufficient thump and slap, while a tambourine sounded great with no audible distortion, nor converter nastiness (tambourine will reveal bad preamps and converters, in my experience). Bass DI’d through input 1 set for instrument level/impedance was plenty fat, yet plenty articulated, too. A pair of condensers on acoustic guitar showed realistic reproduction and a wide soundstage. A variety of synths tracked perfectly though the line inputs. I did find myself wishing for high pass filters and a polarity flip, which aren’t at hardware level or included with UC Control—a big oversight, in my opinion. The mic pres range is 0 dB to +60 dB, and that zero starting point was handy, let me tell you—those were hot mics! The headphone outputs sounded great, too: plenty loud, nice, flat and easily routable.

For $1,000 street, it looks to me like PreSonus has a real winner here. Yes, considering its competition, it’s a “budget unit,” but the construction is pretty darn good; the features are more than respectable (if not entirely complete) and the sonics are excellent. The fact is, I could barely tell the Quantum apart from my usual top-shelf, premium-priced system. There are still a few inconveniences associated with desktop production, but this Quantum dramatically minimizes those issues. It’s a truly competitive audio production product in every way, delivering bang-for-the-buck in proportions I have never experienced before.

PreSonus • www.presonus.com