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Maxon ST-9 Pro+ Super Tube Pedal Review

A variation on the classic green overdrive

Download Example 1
Three licks: No mid enhancement, Low mid enhancement, High mid enhancement, then all three repeated with bass boost. Strat, bridge pickup.
The Ibanez TS9 Tube Screamer remains one of the benchmark overdrive pedals—a proven, go-to device for players seeking extra drive and grit from their amplifier. The many clones of the TS9 (and it’s predecessor, the TS808) now on the market are evidence enough of the Tube Screamer’s classic standing. But now many of these clones also offer subtle improvements on the Tube Screamer circuit, as well as variations on less celebrated versions of the Tube Screamer originally offered by Ibanez.

One such variation, the Ibanez ST-9 Super Tube Screamer, was manufactured by Maxon for Ibanez in very limited numbers in the mid ’80s and was coveted for its additional Mid Boost control. And with eBay prices for this rare Tube Screamer creeping steadily upward, Maxon—which builds its own excellent clones of the TS808 and TS9—is offering a new version of the ST-9 that adds some very practical tone-shaping extras.

Seeing Green

The ST-9 Pro+ is based on Maxon’s “808” overdrive circuit—the original Tube Screamer incarnation made famous by Stevie Ray Vaughan, among others. It boasts knobs for Level, Drive, and Tone (which cuts or boosts treble frequencies), as well as the signature green enclosure familiar to any Tube Screamer user. But the ST-9 Pro+ also offers an additional Mid Enhance control, which boosts the lower mids when turned counterclockwise and the upper mids when rotated clockwise. And because some players complain they lose low end when using a Tube Screamer, Maxon has also included a Low Boost mini-toggle switch.

Hearing Blues … and More
To test the Maxon ST-9 Pro+ Super Tube, I used a 1965 Fender Stratocaster with DiMarzio Virtual Vintage pickups through Orange Tiny Terror and Egnater Rebel 30 amplifiers.

For all its options, the ST-9 Pro+ is not quite as “plug-in-and-play” as the original TS9. On the other hand, it offers a wider range of coloration than a standard Tube Screamer and rewards a little time spent tweaking knobs with some awesome tones that range from gritty blues to snarling rock.

While the Mid Enhance adds considerable flexibility, particularly if you’re switching between amps, some of the most interesting results came from the pedal’s Low Boost switch, which works nicely in concert with the Mid Enhance and Tone controls. If you play at relatively loud stage volumes or use a 4x12 or a 1x15 cabinet, this bass boost might muddy your tone. But at lower volumes, or with single 10" or 12" speakers, it can be invaluable for adding heft behind the inherently cutting tone of the ST-9 Pro+. It’s not unlike a home stereo’s loudness button, boosting the low (+12 dB at 100 Hz) frequency, but also kicking up the mids (+4 dB at 500 Hz). And even with the Low Boost on, the Mid Enhance and Tone controls remain effective for fine-tuning heavier, bass-rich sounds.

Another useful addition is the 9-volt/18-volt option, which is activated via a switch that’s easily accessible through the flip-top battery compartment. In the 18-volt setting, the DC-to-DC voltage doubler circuit increases the pedal’s headroom, frequency range, and dynamic response. And at higher volumes, the 18-volt setting tightened up the tone considerably, which was especially useful when driving an already distorted amp.

The Verdict
It is hard to improve on a classic, but with the ST-9 Pro+ Super Tube, Maxon has effectively produced an Über-Screamer. There is nothing transparent about this pedal: The ST-9 Pro+ retains the essential TS coloration and feel, regardless of how you twist the knobs. And legions of Tube Screamer-style overdrive users will surely find that a good thing. If you’re a fan of the breed, but have always wished for more control over the mids, more low end, or more headroom, this pedal is for you.

Buy if...
you want a TS808 on steroids with enhanced versatility.
Skip if...
you need more aggression in your dirt.

Street $206 - Maxon -

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