Retro Instruments: 500PRE 500 Series Tube Preamp

Years back, when I installed my console and sidecar, I sold off most of my outboard preamps. I was looking forward to a new era of not having to choose preamps, and instead just getting on with what mattered, like listening to the instrument in the room, choosing flattering mic placement, and paying attention to arrangement and performance. Burned out on the minutiae of matching preamp to source, I welcomed the simplicity of choosing just "fast" API 212 or "slow" Neve 1084 preamps. My mantra became, "You don't need a lot of options, only one or two good ones." As such, checking out a new preamp didn't carry quite the excitement for me that a new EQ or dynamics module might, but my deep and unrelenting love for the Retro Instruments Sta-Level [Tape Op #66] (that I've used on about every project in the past 12 years) suggested that the new 500PRE might be a unit worth looking into. To quickly sum up the rest of my review: it is.

While unboxing the 500PRE, I got a little giddy. This preamp looks and feels fantastic. The controls all have a nice substantial feel to them, the faceplate doesn't feel crowded, and the Retro signature grey finish looks great – all in all a very professional feeling piece of equipment. You get Input and Output gain controls, along with toggles for gain range (Low or High), phantom power, and polarity. I was eager to get the Retro racked up but ran into an issue. The 500PRE draws 160 mA, which is above API's VPR Alliance standard. While most newer 500 Series racks will deliver the necessary power for the Retro, you might want to double check if you've got an older rack. I only had 130 Ma per slot available, and had to pick up a new rack – in my case, a secondhand Purple Sweet Ten [#100] – to provide the needed power. Retro recommends a linear power supply, but I've encountered no issues using the Purple's internal switching supply.

So, where's all that juice going? The 500PRE contains three 12AT7 tubes, CineMag transformers, and is rooted in the Sta-Level circuit, offering up to 76 dB of gain. In my earlier days, when I'd run low on options, I'd often utilize the Sta-Level as a mic preamp by plugging in a tube condenser mic and taking advantage of the substantial amount of gain on tap. It always sounded thick, so my expectations were high.

Ahead of my first tracking session with the 500PRE, I took an evening to run some line level audio through it to get a sense of what this preamp sounded like. Retro advertises the unit as a capable limiting device when pushed over the tube clipping threshold – and as well they should! Synths that were feeling a little flat and sleepy suddenly bristled and jumped forward in the mix. Dialing in just enough grit was unusually easy; the saturation slope on the 500PRE is wonderfully gentle. If you've ever wrestled with a mic or line preamp, trying to eke out the right degree of saturation before it goes to papery, crapping-out fizz, you'll appreciate the 500PRE. It'll certainly take you to that blown out static-blast level of distortion should you want it, but you've got plenty of more useable, predictable range ahead of that extreme. Even at moderate levels without audible limiting, the circuit left a pleasing imprint on the audio – altogether a little more exciting than your average preamp.

On day one of tracking with the 500PRE, I first set it up with a Telefunken M82 [#102] on snare drum. I'd never really used tube preamps on close drum mics in the past, but having heard the way the 500PRE could ease into gentle harmonic grit and unobtrusive limiting I wanted to hear how that translated on a much more transient-heavy source. Good news: it worked really well! I was able to dial in enough saturation to help bring out a little bark from the drum without it getting too tone-heavy or turning hi-hat bleed into a mix time nightmare. The Retro cut through an overdriven Vox AC30 guitar amp wonderfully without suffering any low end loss. Experimenting between takes, I was pretty amazed at how I could gain the pre up in High range to find a setting where dynamic response was clamped down hard enough that my snare mic was printing distinct and balanced kick drum as well – it could pass for a close in "crunch" mic for the whole kit, yet without harsh distortion or heavy compression envelope artifacts. I've never heard that kind of response from a mic preamp before.

For our next track, I moved the 500PRE over to the front of the drum kit, powering a Coles 4038 aimed into the ground a couple of feet from the kick drum. I drove it pretty hard, and the Retro added a nice texture that blended in easily with the other drum kit mics. As we moved into overdubs, I set the 500PRE up for acoustic guitars. I was recording with The Beanstalk Library, a band that writes guitar driven songs in the vein of Tom Petty or George Harrison, with a lean towards power pop. We were laying a couple tracks of strummed acoustic in, and I was again pleased to be able to dial in the right degree of transient softening without compromising the fundamental tone. However, be advised – the slope from saturation into distortion is so smooth with the Retro that it can sneak up on you! During a bass overdub with an Ampeg B-15 amp in the control room, the influence of the amp against my monitoring prevented me from hearing that I'd dialed in a little bit too much of a good thing during the first take, and I had to ask the bass player for a redo with the preamp backed off a little.

My next session was with Swamp Rabbit, recording a song with a great gently-churning gauzy lilt – a hazy, jangling Lou Reed feel. I used the Retro on an electric guitar amp during live tracking, and for Farfisa and Ace Tone organ overdubs. There are only a couple of sources where I start splitting hairs with preamps, and electric guitar amps are one of them. Amp. Mic. Neve 1084. If I stray from that, it may still work, though I'm usually a slight bit less happy about it. No such misgivings with the 500PRE. I briefly swapped between the two and felt like (outside of EQ) I wasn't losing anything stepping away from my tried and true process. Varying the gain staging to suit the source, I was without exception pleased with everything we recorded through the Retro. It's easy to be seduced by the instant gratification of that harmonic glow and overdo it, but if you deploy it strategically, you'll be rewarded with loads of great texture and surprisingly little loss of definition. It's not all about grit, though; when used at gentler levels, the 500PRE has a rich, euphonic tone that is colored but not overstated, and there's no reason to pigeonhole this thing as an effect or character pre – it can totally be your do-all mic preamp. For backing vocals, I kept the Retro running pretty clean and achieved a great sounding track that blended in well with the lead vocal – clear, but far from sterile, and definitely flattering. Lead vocals were sung through a Bock Audio 251, which sounds amazing but sometimes comes off a little too squeaky clean in the mids for some material. Running the 500PRE just a little hotter gave the vocal great midrange traction without unduly exacerbating sibilance or obscuring pronunciation. With the Sta-Level next in the chain, the vocal was locked in, and fit right where I wanted it – present and clear but tucked into the mix rather than on top of it.

Aside from being a bit more particular about the rack that powers it, there's little to complain about here, especially for the price. Even at high gain settings, signal to noise ratio was impressively good. The noise floor native to the source (or the room!) always became an issue before the preamp's did. The unit does run about as hot as you'd expect from its three enclosed vacuum tubes, and only time will tell what that may mean for its lifespan – though it's worth considering Retro's reputation and trusting that this consideration did not go unplanned for in the design. I'll be leaving some space above the 500 Series rack to be safe. Ably handling most any recording scenario with gobs of gain and a wide and controllable texture palate, this preamp reduces my desire to patch in compressors at tracking while providing exciting harmonic and limiting possibilities at mix. The 500PRE has won me over, and I'm hoping to have a pair permanently parked in my rack.