Radial JDX Amplifier DI Box
Not that I’m trying to get murdered
in my sleep, but I think it’s safe to
say that when you’re gigging the local club
circuit, the quality of sound crews is wildly
inconsistent. One of these days, I’ll write
a tragi-comedy about the myriad ways a
dunderhead can mic a simple 1x12 cabinet
to transform a decent guitar sound
into total ass. But, to be fair, it isn’t the
easiest job for a soundperson to deal with
three or four completely different band
setups, rigs, and performance styles in an
evening, and the gremlins of over-amped
stage sound and signal bleed are always
in the wings, eagerly waiting to trash all
efforts at delivering a balanced mix to
the audience.
Well, here’s a secret weapon for you.
The JDX ($199 street) is an active, amp
direct box that is plugged in between
your amp head and speaker cabinet. (It
can’t be used as a standard DI for bass,
keyboards, or other direct-injection
applications.) The JDX’s transformer
then acts as a reactive load that simulates
how an amp and speaker respond
to a guitarist’s dynamics, and a speakeremulated
output from the device (miclevel
XLR) can be routed to a mixing
board. Radial’s engineers designed the
JDX’s speaker emulation to produce the
sounds of a closed-back 4x12 cabinet captured
by a dynamic mic. The box itself
is built as tough as an early-’60s fallout
shelter, and it includes ground lift and
polarity switches, a power supply, and a
quite thoughtful neoprene pad that prevents
the box from slipping and sliding.
I brought the JDX to some live
shows, putting it between an Orange
Tiny Terror or a Mesa/Boogie Stiletto,
and either a Mesa/Boogie 1x12 or an
Old Dog 4x12. Obviously, the JDX completely
eliminates the signal bleed of
a live mic placed against your speaker
grille (even when positioned very close
to the speaker, ambient sound can still
sneak into the mic). This is a wonderful
thing if you put your guitar sound in
the stage monitors, because you get a
clear and articulate punch, rather than a
somewhat diffused and midrange-cranky
splatter. During soundcheck, I had
the other guitarist play along with
the band, and I compared the mikedcabinet
tone (a Shure SM57 right on
the cone) and the JDX sound through
the main house system. The JDX produced
a tight and dimensional roar
that sounded very close to an album
track, and the SM57 captured everything
we love about guitar tones live,
but with less string-to-string clarity.
Both sounds were cool, but I was sold
immediately on the JDX’s precision
and impact. Wow. This puppy rocks!
And the JDX also eliminated some
setup stress on a particular gig. When a
club didn’t have enough mics available
to cover our percussionist’s needs, I just
said, “Don’t bother to mic the guitar,
then. I’ve got this red baby coming to
the rescue.” Smiles all around—ya gotta
love that.
Kudos: Excellent sound. Rugged. Easy
to use. Gig saver.
Concerns: None.
Contact: Radial Engineering, radialeng.com
Radial Tonebone PZ-Pre
I play horrid and dirty slide
blues using a faltering Kay archtop with
an old, pawnshop magnetic pickup (brand
unknown) screwed right into the top,
and an ancient Barcus Berry Hot Dot on
the bridge. Figure out how to make that
combo work reliably.
Well, this is the kind of challenge
the PZ-Pre ($299 street) was born
for—although it’s more conventionally
conceived as an acoustic preamp with
multiple features (3-band EQ, feedback
elimination, notch filters, an effects
loops, four outputs, a dedicated tuner
output, a ground lift, a phase-reverse
switch, a mute button, and more) that,
thanks to a class-A booster circuit, maximizes
the output and performance of
piezo pickups. For my needs, however,
I enlisted the PZ-Pre to either blend my
Kay’s two pickups into a much more
musical sound, or switch between the
Kay and an Epiphone Casino. As the
PZ-Pre can handle almost any type of
pickup input—magnetic, piezo, or internal
mic (as long as phantom power is
not required)—I was ready to roll.
The PZ-Pre’s output section is a marvel
of Zen design—it’s simple, yet in harmony
with P.A. systems, guitar amps, and
powered speakers. I could use the Post
EQ balanced XLR output to send signals
directly to the front of house mixer,
but as I was playing a dive bar, I opted
to route this output to a Mackie Thump
powered speaker. The Pre EQ balanced
XLR output was perfect for running a
signal to my Fender Deluxe for some tube
mojo, or keeping things clean and sparkly
by running into another Thump. I could
also opt to use the Tuner output to run a
third amp (brought in and out of the mix
via the Mute footswitch) for even more
massive guitar textures.
During a soundcheck for a club gig, my
Kay immediately vibrated and howled like
a banshee. Happily, I could tame the resonance
by setting the Notch Q switch to
Normal (-8dB) and tweaking the Notch
Frequency knob to around 300Hz (full
range is 56Hz-330Hz). I was also jazzed
that a mere flip of the Lo-Cut switch
killed the 60-cycle hum produced by
the club’s wretched AC power. Finally, I
tackled the PZ-Pre’s EQ to dial in a big
and articulate tone, as well as coax more
output volume before feedback. As both
inputs share the EQ section, I compromised
a bit on the Casino’s sound, as it
was far more important to get a ripping
Kay sound out in the room. For solos, I
ran a Boss Blues Driver (set to a tweedlike
grind) and a Fulltone OCD pedal
(cranked to the verge of feedback) into
the PZ-Pre’s effects loop, and brought in
the roar by stepping on the Boost footswitch
and adding a bit of helpful gain
with the Boost level control.
By now, I’m sure you can surmise that
the mind-blowingly cool thing about the
Radial PZ-Pre is its versatility. There’s
almost nothing you can’t do with this
interface—no matter what kind of acoustic
or electric instrument you play.
Kudos: Incredibly versatile. Gig tough.
Concerns: None.
Contact: Radial Engineering, tonebone.com