Retro Instruments made a splash about five years ago with its replica of the classic Gates Sta-Level compressor (Tape Op #55), and then again in recent years with products based on the Universal Audio 176 variable-mu compressor (#66) and the Pultec EQP-1A3 passive/tube EQ (#79). This time around, Retro’s Phil Moore has designed a channel strip to live up to the quality the brand connotes.
At first glance, it’s easy to overlook the fact that the Powerstrip is partly a mic preamp (at least for those of us that read left-to-right), because the input control is on the right of the faceplate, over with the compressor and output controls. The far left of the box does contain a phantom-power switch, polarity flip, and input selector (mic, line, or instrument), as well as a 1/4’’ DI input. The rest of the left side is dedicated to the Pultec-style EQ, with all the customary boosts and cuts; frequency selections (with a few extra HF frequencies); and bandwidth control for the HF band. In the middle there’s a switch for the low cut, which applies a 40 Hz or 90 Hz filter to whichever input is selected. On the right are the input and output controls, which feel like the gain staging on an 1176, as well as the compressor controls, which are simply the time constant (six selections from slow to fast) and the sidechain filter (off, 90 Hz, or 250 Hz). Again, like an 1176, there is no threshold; if the compressor is engaged, the input level determines how much compression is applied.
The gain staging for the mic preamp, with the input and output knobs, takes some getting used to, because it’s not really like any mic preamp you’ve ever used. Sure, I have mic preamps with separate gain and trim controls, but the Powerstrip’s gain controls just feel a little different, and I’m not sure why. There’s no metering for input or output level; the oversized needle meter only shows gain reduction of the compressor circuit. When driven hard, the input saturates dreamily. This is up amongst the best mic preamp distortion I’ve ever heard, with zero nasty artifacts — only creamy overdrive. On acoustic guitar, bass, vocals, and drums — mmmmmm, I like. But it doesn’t only sound good when driven hard. With the input in a sane place, the Powerstrip has boatloads of super-clean, ultra-open gain, giving me new perspective on my ribbon and dynamic mics. This is the kind of preamp that rekindles your love with your mic collection. With a Sennheiser MD 421 on a guitar cab, I heard astonishing new detail and presence, even compared to some of my favorite preamps. Royer R-121 (Tape Op #19), Beyerdynamic M 160 (#60), Sennheiser MD 441 — even my beloved vintage Neumann U 87 — sounded a notch or two better through the Powerstrip’s microphone preamp. More top end, a richer midrange, and beefier lows, all at the same time. Line and instrument–level signals get a similarly euphonic treatment; I think I found my new favorite bass DI.
If things didn’t sound good enough already at the input stage, you can make them sound even better with the Powerstrip’s EQ. The low-end boost sounds remarkably good, especially when coupled with the subsonic filter, which allows you to boost low end without smearing the bottom of the bottom too much. The high-end boost has ten selectable frequencies, from 16 kHz all the way down to 1.5 kHz, which I found really useful for kick drum and electric guitar. This is not a surgical EQ; it excels at giving instruments a “lift” and just making them more exciting to listen to.
The compressor circuit, which is Mr. Moore’s take on the EMI RS 124, is exceedingly smooth. Even without the sidechain filter engaged and at the fastest time constant, high amounts of gain reduction contain no negative compression artifacts. The tube-based variable-mu compression circuit is remarkably transparent, while still being adept at level control. The sidechain filter is a great feature, to boot. Fellow engineer Jay Pellicci, who is a dedicated Retro Sta-Level owner, commented that the compression circuit reminded him of the Sta-Level, but got a little bit faster. He also remarked that while the Powerstrip excelled for him as a line-level device, it was tricky to set the gain staging right when using the compressor for a mic level, since the mic input gain is tied to the compression amount. I agree that it’s a little tricky, but I’ll add that once you get it set right, it sounds really good!
There are two somewhat hidden bonus features on the Powerstrip that are also worth mentioning. The first one is very hidden; the input knob is also a pull-switch for engaging a “vintage” sound for the input stage. I found this mode a little too dark for most applications, but if your sound source is really bright, it’s a handy way to get a rounder tone without using subtractive EQ. The other feature is that the back of the unit boasts both an instrument thru jack, which is a straight mult of the DI input, as well as a Hi-Z output that is post-processing. This not only turns the Powerstrip into a super-deluxe EQ and compressor for your onstage guitar and bass sounds, but it also means you can use the Powerstrip as a re-amp box, with the ability to add EQ and compression to your line-level signals on their way to a guitar amplifier or pedal chain. I loved using this feature to split my signal during a mix — one channel straight from the line output of the Powerstrip, and a parallel channel going through pedal processing.
The obvious question — is the single-channel Powerstrip worth its near-$3000 price tag? For some of Tape Op’s readers, it will seem like a total bargain, since it does so many things so well. For other readers, it’s more than you spent on your last two cars, combined. Bottom line — it will make your life easier, assuming your life revolves around trying to get good sounds. Every time I send signal through the Retro Powerstrip, I get a smile on my face, and that kind of happiness is just about priceless. ($2895 street; www.retroinstruments.com)
–Eli Crews, www.elicrews.com
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