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Zon Sonus RT5K 5-String Bass

Robert Trujillo's pounding, aggressive basslines have carved a wide swath of destruction through 15 years of hard rock. Trujillo's signature ax, the U.S.-made Zon Sonus RT5 (list price $2,595), is a solid and inspiring tool, well suited to the demands of high-performance mayhem. The RT5K is a Korean-made version that retains the high-end feel and tone of the U.S. model, while saving you a cool $900.

"We set out to make a high-quality instrument that was affordable for younger players that wanted to get Robert's sound," says builder Joe Zon. "We spent close to a year with Robert on his bass, dialing it in to get the tone he needs for his gig." While Zon is known for their graphite-composite necks, Trujillo wanted a wood neck to capture the appropriate vibe for vintage Metallica material. The 24-fret, threepiece, bolt-on maple neck and South American pau ferro fingerboard are rigid and stable, and the instrument's slim profile gives it a lightningfast feel. The neck extends deep into the body, and four countersunk bolts insure rock-solid dependability. The two-piece maple body has a quilted maple veneer that adds a subtle beauty, and the polyurethane finish is buffed to a glasslike gloss.

  • The controls are easy to figure out-the master volume knob is first, followed by a pickup- blend pot. A concentric bass/treble control is closest to the bridge, leaving the mid control on its own (each knob gives you 15 dB of boost or cut). Citing reliability issues with pop-up battery compartments, Zon chose to tuck away the 9-volt inside the instrument's tidy, shielded control cavity. Zon claims 300-400 hours of continuous battery life, so you shouldn't have to change it all that often, but I'd still like to see a passive bypass as a fail-safe feature. And you never know-there might be some cool passive tones locked away in there, too.

Weighing in at a reasonable nine pounds, the bass sat comfortably on my shoulder. The upper horn's strap attachment point is in line with the 13th fret, and thanks to Zon's compact and lightweight 3+2 headstock design, the neck didn't dive. The RT5K model uses Korean-made Zon pickups built to the specs of the EMGs found in the U.S. model, and a Zon preamp that emulates the more expensive Bartolini 3-band EQ.

The RT5K has the same precision-machined brass bridge as its older brother. The taper down to the 1.83" graphite nut makes the neck's overall playability very comfy, the 17mm string spacing is great for slappers, and, much to my delight, the 34-inch scale feels like home. The bass came supplied with Zon's own stainless steel five-string set, which felt snappy, with a nice balanced tension. The strings were bright, but not so much that you'd want to "cure" them in fried chicken grease before using. Every Korean-built Zon goes through the U.S. factory for final setup; my test instrument came right out of the box in perfect order, ready to rock.

Plugging the RT5K into my Genz Benz GBE 1200/NEOX-212T rig (set flat), I was immediately impressed with its massive low end-and I hadn't even begun to tweak the onboard preamp. This bass definitely contradicts the myth that you need a longer scale length to produce a strong and articulate B string! With the lows centered at 30 Hz, you can get evil on the B string, and the bass didn't feel like it needed help. The mid frequency is set at 400 Hz, which works great for adding fingerstyle articulation. 3 kHz was chosen for the treble center frequency; it's a bit edgy compared to the super-slick sheen of modern hi-fi tone, but edge is what keeps you from getting buried alive when you're backing up the most notorious axmen in metal.

Even though the single-coil pickup placement is identical to that of a Seventies-era Jazz Bass, I found the RT5K had a deeper, chunkier tone. The bass's slap tone seemed balanced more toward the front pickup than the bridge; Zon says the pickup windings-combined with the active circuit-give it that "barkier" quality. Trujillo chose a maple body, preferring its more cutting tone for rock and metal. And cut it does: The RT5K speaks quickly with a tight, focused edge. There's plenty of balls, but the top end is sure to get you heard through the maelstrom.

Although it's the lowest-priced entry from a company that builds instruments in the $4,000- $7,000 range, the Zon Sonus RTK5 is still a very serious ax. Zon has maintained its high standard of quality while managing to keep the price well under $2,000. With its fast-playing neck and versatile, synergistic design, the RTK5 can sit well in a hard-rock mix, function as an evil slap machine and slap the devil out of funk, or be warmed up for rootsy applications-a wicked tool, indeed.

These samples were recorded into a Digidesign Pro Tools system using the analog output of the Line 6 Bass PODxt Pro. No additional EQ and only minimal compression was used.

TRACK 1 Using mostly the bridge pickup through the Line 6's Ampeg SVT model, I dialed in a nasty pickstyle tone that clearly articulates the low notes.

TRACK 2 With both pickups up full, I used the Zon's midrange control to bring out the clarity in this low and evil fingerstyle groove reminiscent of something Trujillo may have played in the Ozzy days. I used the SoCal Metal preset on the POD, which is a cleaner, modernmetal setting.

TRACK 3 Back to the POD's more toasty SVT preset: I used the bridge pickup to get some kind of monster tone. This bass has terrific fingerstyle definition through its entire range.

TRACK 4 We know the RT5K can rock, but it also warms up nicely to get a clean, fat R&B tone. Through the PODxt's Eden model, the bass gets a punchy, defi ned tone that lets the faster notes speak.

TRACK 5 Trujillo is well known as a slap monster, and his bass just begs for a spanking. With a tube D.I. model, I got a super-aggressive slap tone that will boldly stand up to thrashy guitars.

TRACK 6 Just to show off the RT5K's versatility, I switched to the neck pickup and pumped out some fatback blues. With the PODxt's Ampeg B-15 model, this setting produces a warm, round, downhome tone.

TRACK 7 The upper register of the RT5K sounds great, too. Through the Line 6 Eden model, with emphasis on the bridge pickup, and some mids dialed in from the onboard preamp, the bass really pops when playing fast bebop lines.

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