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‘Grace’ your pedalboard with a studio-grade preamp


Review by Alex Hawley

Based in Lyons, CO, Grace Design is renowned for its highly respected ultra-clean microphone preamps and advanced mastering-grade monitor controllers. Since its inception in 1994, Grace Design has also played in the stompbox arena. The popular FELiX (which I reviewed in the December 2015 issue), ALiX, and BiX offer studio-grade instrument preamplification in a foot-pedal style chassis. The latest Grace offerings on review today, the fully featured and larger ROXi and the streamlined REX, are unique in that they center around the company’s studio mic preamps while adding a few extra tricks.

Grace Design RoxiHello ROXi

We’ll start with the fully loaded ROXi.

ROXi features a combo XLR / 1/4 input paired with a stepped gain control ranging from +5dB to +60dB. This range can be further pushed by engaging the ‘Boost’ foot switch with the corresponding pot, which ranges from 0–10dB. With a total of +70dB of potential gain on tap, there’s plenty of juice to power gain-hungry dynamic or ribbon mics without a problem. Boost also serves well as a ‘more me’ clean boost while performing live.

The input can be shaped with a three-band EQ featuring low and high shelves and a sweepable midrange, all with +/- 10dB of range. The low shelf is fixed at 125 Hz (corner frequency) and 40 Hz (peak frequency), creating a gentle and musical slope. The high shelf offers a similar slope, with a 2 kHz corner frequency and 12 kHz peak frequency. The sweepable mid band has a fixed Q and ranges from 175 Hz to 4 kHz.

The ‘Amp’ pot controls the output level for the dedicated 1/4 amp output jack on the rear panel. Unity gain is at 12 o’clock (matching the main XLR DI output level) but can be adjusted +/- 10dB to drive the front end of your amp harder (or softer) as desired.

The rear panel also features a 1/4 tuner output (paired with a mute/tune foot switch on the top), an IEC power connector, and push buttons for 48V phantom, phase flip and ground lift.

In the Loop!

One of the most exciting aspects of ROXi is undoubtedly the FX loop. The back panel features 1/4 send and return jacks to loop any guitar pedals with your microphone input (at the proper level and impedance for those effects). Now, you can design custom pedalboards to use live on vocals, banjo, brassanything you can mic.

The ROXi features a dedicated pot to control the wet/dry balance of the FX loop, which offers further creative potential. You can run connected drive, verb or delay pedals a bit wetter than usual and season the wet/dry blend to taste as you play. One quirk is that the wet/dry blend stays active even when the FX Loop is inactive (via the footswitch). In theory, that ensures a consistent level when switching it on or off, but if you run the FX loop 100% wet, the output will be effectively muted when you toggle off the FX Loop. If you want to run 100% wet, leaving the FX loop permanently engaged works best while just toggling the individual pedals on/off as you play (essentially how the REX worksmore on that later).

Take a DIP

The side panel offers an additional row of DIP switches. While they are small and tricky to adjust without a guitar pick or similar, the DIP switches are accompanied by a cheat sheet printed on the side panel for easy reference.

The first switch toggles the DI output between mic and line level. Switches 2–3 control the high-pass filter (toggling 75 Hz vs 15 0Hz, and on/off respectively). DIP Switch #4 sends 12V to the combo input jack for use with electret capacitor mics, while switch #5 enables a dedicated 9V 500mA barrel output on the side panel for daisy-chaining your pedals together (as long as the pedals don’t add up to exceed that 500mA current rating). The final DIP switch toggles the corresponding left foot switch between boost or FX Loop.


The back of Grace Design Rex and Roxi

Grace Design Rex closeupHello REX

REX offers similar features, only streamlined in a more compact footprint. Starting with the rear panel, REX offers an XLR input (not a combo jack like ROXi), again paired with a stepped gain knob. The EQ section is limited to the high and low shelves (missing the sweepable midrange) and a toggle switch to engage a 75 Hz high-pass filter.

The FX loop has the same dedicated 1/4 I/O without a wet/dry blend control. The FX loop is always on, so you’ll need to rely on turning any effects on or off at the pedals themselves rather than the global foot switch like on the ROXi. The ‘send’ jack can also act as a dedicated tuner output without the need to use the ‘return.’

The final pot on the top panel (in addition to the stepped gain knob and low/high EQ shelves) is the dedicated boost (up to +10dB), engaged by the left foot switch. There are no additional DIP switches on the side panel of the REX.

The rear panel also includes the 1/4 amp output, XLR DI output and a 9V DC barrel power connecter (as opposed to the full IEC connection needed for the ROXi).

Playing with ROXi and REX

ROXi and REX are geared for live use, but they absolutely compete with any high-end rack-mounted preamps in your studio. The preamps are clean and extremely low noise while offering ample headroom and clarity. Packing a top-notch preamp for every gig enables a more consistent and reliable sound, plus you get the added flexibility of using pedals on voice or other acoustic instruments.

I did most of my testing in the studio on vocals and acoustic guitar. Adding a tap tempo delay on the voice gets instantly creative, especially if you start throwing expression pedals into the mix. The DigiTech Whammy pedal also provided some wild vocal fun. I particularly enjoyed the octave doubling for a unique, real-time vocal effect. Here, the wet/dry blend played nicely, giving control over how loud that doubled octave sounded in the mix. The potential here is truly limitless.

The sound designer in me couldn’t help but use this as an opportunity to mic and record everyday sounds through various guitar pedals. Mangled sounds with overdrive, whammy and a tape delay contributed to some unique recordings and outside-the-box sound effects.

Grace did an excellent job distilling the most essential features from the ROXi into the REX. On the ROXi, I typically ran the FX wet/dry blend at 100% anyway, so omitting the dedicated pot wasn’t a big deal (for me). The biggest thing I missed on the REX was the mid-band EQ. But with the low and high shelves still on board, plenty of tone shaping is still available (and you can always employ an EQ pedal in the loop to bridge the gap). The REX is also easier to fit onto a pedal board, especially considering the 9V barrel connector instead of an IEC for power. The little sibling packs a punch!

Final Thoughts

Both the ROXi and REX are thoughtful and well-designed. Anything built around a Grace Design mic preamp is already destined for greatness, but the rest of the features elevate the whole experience. They are compact, rugged and road ready. The Grace Design pedigree is fairly reflected in its price tag, but this investment will last years. That’s right, vocalists…it’s your turn to start buying pedals and loading in some of your own gear to the gig!


Price: $895 ROXi; $585 REX

More From: gracedesign.com


Grace Design - Roxi set up on guitar pedalboard