Q2 Audio: ADR Compex F760X-RS dynamics processor

I've been thinking a lot lately about how we evolve as engineers, and in a way, it's my favorite part of the job. You wake up one day and realize you are doing something totally differently, like the day I realized I'd stopped obsessively fighting phase issues between bass DI and mic signal. In this case, a piece of gear helped — the Little Labs IBP [Tape Op #33]. As time goes on, I notice I'm not fighting for sounds as often. This is due to the fact that I've been making records for a while now, and doubtless, the gear here has gotten much better. Recently, I've been noticing the same phenomena in regards to drum sounds here at High Bias — more on this later. This is, however, due solely to the addition of the Q2 Audio ADR Compex Limiter F760X-RS. 

The Compex began life as a limiter used for cutting records, and over time, it was modified incrementally into what it is today with compressor and expander/gate sections. It is a feedback type FET limiter/compressor, which means the sidechain input is taken from the output. The Compex is responsible for the sound you hear on countless records; most notably, it's the box behind the drum sound on "When the Levee Breaks." Due to this, the Compex became a legendary and coveted piece. I've always silently watched eBay auctions and muttered, "Some day...." Enter Tim Mead the genius behind the reissue/improvement of this venerable box. Tim is local to me in Detroit, and he's long been the go-to tech guy here, so when he told me he was working on an ADR Compex reissue, my ears perked right up. He dropped one off one day, and with a short tutorial, I was off to the races. Out of the box, this thing is handsome and sturdy as hell, and setup is as easy as can be. Tim hipped me to the gain-staging and how to dial it in — slightly confusing, but I got the hang of it quickly enough. 

The first task for this box was, big surprise, drum room mics! The band for this date were Atlanta psychedelic dance wizards Hollow Stars. These guys play songs that are long and totally absorb the listener. Drummer Devin Brown is a machine in the best way. He just knows how to hold it all down and keep the groove happening for the duration of these 11 minute jams. Here at High Bias, we have four Shure SM82 mics hanging in the live room at all times. I permanently installed these when we opened 15 years ago, out of curiosity and a desire to hear clients in the room, both while playing and as a communication device, since we don't really use cans here. The SM82 is a broadcast mic that has a crude facsimile of the Level-Loc inside, set at a super-low threshold, and it puts out line-level. The SM82 mics have contributed to the sound of many recordings here, and I've always loved the smashed and distorted sound they make. Plus, I get to pretend I'm Tchad Blake! So I took the room mic bus on this session, which consisted of a pair of the SM82s hanging along the walls equidistant from the kit, and strapped the F760X-RS across it. I felt slightly stupid compressing something so smashed already. If anything, the unprocessed mics were already providing a nice din of drum racket, the kind that makes even the most anemic drummer sound like a pounder. But somehow, the F760X-RS reclaimed the attack of the drums, reminding me of how an SPL Transient Designer [Tape Op #21] can change the envelope of percussive sounds. After tweaking the compressor and expander controls to taste, the result was easily the best drum sound I had gotten in recent memory. From then on, the F760X-RS stayed in this position for a few months with rare exception, and I quickly learned that the F760X-RS really performs — from subtle, barely audible pumping or ducking, to extreme reshaping effects. For sure, sounds take a minute to get to, due to the vast control over the circuit, but settings are easily recallable via the detented knobs that the unit sports. 

I finally moved the F760X-RS when Chris Bathgate came in to record with his collaborative group SKULLLS. Chris is a searcher. His music ranges from rootsy, psychedelic groove folk to astute, new school compositional piano rock. SKULLLS falls into the latter category. Ben Gajino plays drums for this outfit. Ben is one of those drummers that's a blast to record because he can do nearly anything. Intrigued by its fast and aggressive behavior, I moved the F760X-RS from the room mics to the kick and snare. I almost always use a dbx 165 or UREI 1178 in this role. Ben's snare dynamics are intensely expressive, and the F760X-RS did amazing things to the transient response. I started out just adjusting the compression controls and then got into some serious sculpting. This thing can really change the whole sound and behavior of tracks. After drum tracking, we moved on to piano using a pair of Josephson C42 condenser mics [Tape Op #34], Rascal Audio Two-V preamps [#102], and the F760X-RS. The same was true here, and a whole range of sounds was achieved — from barely audible, yet super functional compression, to all-out crusher sounds. This day, I started experimenting with the limiter. The F760X-RS has a 250 μs, 100:1 limiter, that when employed, takes care of any peaks that may have snuck through. We had the compressor and expander set just right for effect, but the initial piano hits were a little intense. I kicked in the limiter, and problem solved. 

The next use of the F760X-RS was for a mix with Beekeepers, a band of free rock upstarts from Hamtramck, MI. They make beautiful and strange art rock. Like Talk Talk meets Tall Dwarfs with David Stoughton. Jeff Else is their drummer, and he records their stuff at home using minimal mics and a simple Logic 9 rig. The sound is very Conny Plank. Super fun to mix. We put the F760X-RS on the drum bus at mix, and it was simply magic. Before I even starting turning knobs, it brought the drums to life in a beautiful way. That's one of the things I noticed time and again — the F760X-RS brings the material to front in a really natural way, and from there, you can continue to trick out the dynamics to really dial it in. On this day, we used the limiter in pre-emphasis mode. This allows the limiter to de-ess slightly, which was handy since Jeff uses maybe two mics on drums, and cymbals can be an issue. The results were perfect. 

Gosh Pith are a New Detroit R&B duo. Their music is smoky and hazy with the dankest trap beats this side of the Mississippi. Josh Smith (get it?) sings, and they, as above, record at home, but in Ableton Live. They do a great job of tracking their songs, so it's usually just them paying me to do a hockey-stick mix, busing it through my trusty Purple Audio Sweet Ten [Tape Op #100]. This day, I used the F760X-RS on the vocal bus. Again, the forwardness was instantly apparent, and I used the pre-emphasis to de-ess the vocals. The vocals sat perfectly — louder than everything else, but not overpowering at all. The F760X-RS's limiter just provides that kind of high-class limiting that you can't hear. 

Scotty Masson is a stone genius weirdo pop songsmith from Ferndale, MI. He cut his teeth in tons of Michigan rock bands in the '90s. Then he went to Chicago with his band The Office. Out of the blue one day, he called and came by to mix his album of expertly recorded jams. Scotty is a gear nerd who's up for anything, so we put the F760X-RS on the mix bus! Since our mix had a lot of low-end information, the F760X-RS seemed a bit grabby on the bassy material, but this was nothing a little side-chaining couldn't solve. The resulting mix was super-polished and slightly more aggressive than we were going for, so we dialed it back, and it was great — upfront and with character, super pro but not too slick. 

Like most engineers, I remember the first time I heard Led Zeppelin, and for me, this totally coincides with the first time I was aware that records are made. Until then, I thought that 25 ft tall rock gods created what was coming out of my dad's stereo. (Gimme a break; I was 9 at the time.) The fact is though, that even to my young ears, I sensed something different was happening on those recordings. A decade and a half later, in the mid '90s, I got a job at the incredible Ultrasuede Studio. We had a "live" room that was mostly carpet, so room mics sounded comb-filtered and weird. I'd put pegboard all over the floors and walls, but to minimal avail. Anytime I worked in other rooms or houses that were more reflective, I'd put the drums somewhere live and position mics where I thought they should go — and then sat there wondering where the "Bonham" was. (It turns out the drummer matters!) A decade or so passed, and I got a room I liked here in Detroit. Still experimenting, we put mics everywhere here. Over the course of 200 or so records, I didn't really realize I was chasing this sound I heard as a youth. Some of this was due to the fact that not every band needs or wants drum sounds like this, and also to the ubiquitous nature of this sound and its imitations. I took it for granted and simultaneously assumed it was unattainable. The F760X-RS has made me realize just how much the fabric of my engineering modus operandi was sewn together with the threads of this box. It's exactly what I wanted for the above applications, and I never knew it until it showed up. Furthermore, I never realized how magic that sound was and how integral it would become to me, even at this stage of the game.