Compared with the big advertising dollar laden professional audio manufacturers, Radial Engineering is a virtual unknown. Ask around in a crowd of particular

OUT OF THE BOX >The Radial Engineering Reamping Pack includes everything one needs to reamp a guitar track. The package includes a J48 active DI for a clean input signal and the X-Amp impedance-matching amp driver.

Compared with the big advertising dollar — laden professional audio manufacturers, Radial Engineering is a virtual unknown. Ask around in a crowd of particular guitar and bass players or live sound engineers, and a handful of faces might smile. Despite their relative obscurity, this Canada-based company has been in the business of making everything, from tube technology to pedals to cables and snakes to custom-shop wall connector plates, for roughly two decades. And so with a 20-year history of making gear capable of weathering the demands of live sound, Radial introduces the J33 turntable DI and Reamping Pack, which includes one J48 active direct box and one X-Amp reamping driver, all nicely bundled up in a Zebracase with a convenient handle. The J48 and X-Amp are also offered as separate units, but here they come as a single package.


I began my testing with the J33. My studio is already outfitted with a Technics SL-1200MKII turntable connected to a similar phono preamping product, an ART DeeJayPre, so I was already familiar with the necessity for such a box. Plus, I had a basis for comparison — not very many companies make these things. The J33, like other more esoteric pedals and DIs, comes in an unassuming, plain white box with just a sticker on the outside to identify its contents. Radial clearly doesn't put its money into a fancy container; yet once you lay your hands on the J33, you can immediately see where its money goes. The Canadian-made box weighs in at an obese 1.5 pounds and feels like it was built for the military. Radial is detail-oriented as well. The bottom of the chassis is covered with a soft foam layer, useful both as a non-slip surface and for isolating the unit from vibrations. The J33 requires either +48V phantom or 15V DC power, and a 15V external power supply is included. One end of the chassis sports a single gold-plated stereo RCA phono input and a turntable ground apparatus, a high-pass Rumble Filter in/out button, and three different -10dB outputs: a gold-plated stereo RCA set, a TRS ¼-inch and a TRS minijack. On the other end of the unit is the power supply jack and a set of stereo mic-level (600-ohm) outputs on balanced XLR connectors.

Short of being an A/D converter, the J33 has every type of output any audiophile could ever likely desire, and they are clearly marked with the pertinent signal and connector-type information. Getting down to business, I disconnected my ART DI from the Technics turntable and replaced it with the brick-like J33. For output, and as a direct comparison, I used the line-level RCA jacks, which connected to my console via ¼-inch line inputs. Though I have no complaints about the audio performance of the ART, the J33 sounded great, adding no audible hum or hiss of any kind to the signal, while transmitting the sound of various well-recorded records ranging from jazz to rock to thumping techno very nicely. As far as construction quality goes, the J33 truly is playing for keeps. Plugging in and out of the RCA sockets gives you the feeling of trust that only a really solid piece of gear can give — the sockets didn't budge one millimeter, even with tightly fitting RCA cables. The ground screw also feels snug and sports a gnarled surface to make it easy to grip. This is very appreciated when dealing with limited surface area or while reaching behind pieces of gear to connect cables. I also tested out the Rumble Filter, which employs a 200Hz cutoff, -3dB slope at 100 Hz to the signal. This noticeably tames the bass frequencies and could prove to be a useful tool in rooms where resonant bass frequencies are a problem. Although already convinced of the quality of the J33, I continued my tests by first plugging the XLR outputs to two mic channels on my console, and then connecting both ¼-inch and ⅛-inch balanced TRS Y-cables to two line inputs on the board. For these tests, I unplugged the J33 power supply and engaged phantom on my console (keeping the XLR cables connected). Everything worked perfectly, and the mic-level signal was noticeably quite hotter than the line levels, as expected. Again, all three types of connections introduced no extra noise into the signal. The J33 performed like a champion all the way around.


Moving on, the Reamping Pack further proves Radial's commitment to quality. Both the J48 and the X-Amp are also built like tanks. The included Zebracase Z12 is a hard-plastic carrying box with a custom-molded foam interior that keeps the J48, X-Amp and power supply for the X-Amp snug and protected. The J48 is an active 48V phantom-powered direct box. On one end, the J48 sports a -15dB pad switch, a 48V presence indicator LED, a ¼-inch instrument input and a ¼-inch signal-thru jack. A unique feature also found onboard is a Merge on/off switch that converts the input and thru jacks to a stereo pair of inputs; these get summed to mono for the XLR output. A balanced XLR 600-ohm mic-level output, a 180-degree Polarity Reverse switch, a -6dB at 80Hz Low Cut switch and a chassis Ground Lift switch all live on the other end of the J48.

J48's companion, X-Amp, is not far off from being a direct box in reverse. On one end it features a balanced XLR 600-ohm line-level input, an input Ground Lift (pin-1 disconnecting) switch and the power supply socket. On the other end you will find a recessed Output Level potentiometer, a Power indicator LED, an input Clip indicator LED, a transformerless ¼-inch output (Direct Out-1), a transformer-isolated ¼-inch output (Isolated Out-2) and a 180-degree Polarity Reverse switch linked to the isolated output. In this instance, the Polarity switch allows you to connect two amps without worrying about phase cancellation, and the transformer-isolated architecture of the second output takes care of potential ground loop problems. A side panel sports an additional Ground Lift switch; this one is indented and affects only the Isolated Out. Both boxes as well as the phono DI employ 14-gauge steel chassis with internal welded I-beam construction and overhangs on their outer plates; the overhangs effectively serve to protect the connectors and switches from damage. These are indeed very well designed products.

For my reamping test, I first recorded some bass tracks to Logic Pro 7 through the J48, played with an Ibanez Soundgear 4-string with active pickups. I then fed the recorded tracks through my console to the X-Amp via XLR and sent the Direct Out-1 to a Tube Works 3030 bass combo amp via ¼-inch instrument cable. There was no need for me to use the -15dB pad, although it did work great when I tried it out. The Low Cut switch definitely does its job of attenuating low frequencies quite well, though again I chose not to use it. The J48 played no part in ground loops, and as a result the Ground Lift switch also was not needed. The straight-to-computer bass recordings were, simply put, clean as a whistle. There was no hum or air introduced, just a clean, fat bass tone. All of the jacks and buttons felt solid as a rock, even when I deliberately jiggled the connectors. I used the Low Cut button to check for phantom power (it performs double-duty), and each time I pressed it, the LED blinked to indicate positive +48V presence. It would be nice if it would stay lit rather than blinking, but it does the job nonetheless. I was already feeling confident when I plugged in the X-Amp, and like the other two boxes, all connections felt solid. I plugged a mono XLR out from my board to the X-Amp, set the X-Amp's Level pot to zero and connected Direct Out 1 to the Tube Works amp. In order to feed it a good, hot signal, I gradually raised the Main Out volume on my board until the X-Amp's Clip indicator was blinking and then backed off just until it wasn't blinking. I turned the amp's volume up just enough to produce sound, and then I swept the X-Amp's Level pot from zero to ten. The pot has just the right amount of resistance, but a full sweep felt perfectly fluid. Though it has a textured edge useful for gripping with a pair of fingertips, it is partially recessed with a flat crevice on the top; it is definitely designed to turn via screwdriver or other similar thin tool (such as a dime or guitar pick.) It is advisable to use such a tool, as turning it with your fingers is doable but uncomfortable. Even with a hot incoming signal and the output Level set to ten, X-Amp produced a clean, full, distortion-free signal. When I raised the Main Out on my board to deliberately clip the signal, X-Amp's Clip LED proved to be an accurate indicator of distortion. X-Amp has a good amount of headroom, but the LED doesn't lie. Next, I switched to the Isolated Out, and here I found the indented Ground Lift switch to be useful. Though without it engaged, the signal was still fairly clean, when I engaged it, much of the dead air that was present was effectively removed. And even though for my tests there was no special need for the Polarity Reverse, as the signal emitting from both outputs is likely to be nearly identical, this switch is a definite plus for those who plan to use both outputs simultaneously with multiple amplifiers.


This review was my first hands-on experience with any of Radial's gear; suffice it to say, I was impressed. The J33 does a fine job of transforming a turntable's RIAA output to a flat line-level signal. But more than that, it provides enough of a variety of output connections to please even the pickiest of DJs or engineers. The Reamping Pack is an interesting combination of devices that should spur the imaginations of plenty of recording engineers out there, and both the J48 and X-Amp are excellent units in their own right. The addition of the Zebracase renders the entire package certainly road-worthy, but it is in the quality of craftsmanship that all three of these Radial products truly shine. You can feel it when you pick them up, and you can hear it when you plug them in. The J33, J48 and X-Amp are built as hard as diamonds and sound as clear as crystal. Whether you are a serious vinyl collector looking to properly transfer your wax to disc, a gigging musician who needs a top-shelf DI, or a creative engineer looking to experiment with the reamping concept, these three Radial products get a serious nod of approval from this reviewer.


J33 > $200


Pros: Great sound all around. Supersolid construction. Good variety of professional and consumer I/O. Power supplies included as needed, +48V phantom power enlisted with J33 and J48. Intelligent labeling on units, well written and illustrated user manuals.

Cons: None.