Genzler Amplification: 4 ON THE FLOOR Classic Bass Overdrive

Jeff Genzler has been a very busy guy. After arguably one of the worst years for the usage of – and thus desire for, ostensibly – products that communicate an electric musician’s musings to large groups of people in a live setting since music became amplified, Genzler Amplification came out swinging in 2021 with the release of not only a brand-new series of bass speaker cabinets and a new amp channel-switching pedal, but also a first for the company: a uniquely designed and fully-featured effect pedal. As an interesting and fun note, the project was the fruit of a professional reuniting of Jeff Genzler and Andy Field; the latter being the principal engineer during the Genz-Benz days, having since moved on to designing for MESA/Boogie®.

The 4 ON THE FLOOR™ Classic Bass Overdrive is clearly marketed as an (all-analog, true-bypass) overdrive pedal, but I’ve found it can be used in so many ways as to want for a broader category of description. Due to its very cool filtering capabilities of the overdrive circuit and ability to control both that output and the clean output separately, the 4 ON THE FLOOR easily covers ground as a clean boost, novel megaphone-style lo-fi production effect, bass fuzz, overdrive, somewhat of an amp simulator, and even as a lead channel distortion in the right contexts, too. 

On the 4 ON THE FLOOR, we’re given variable low-pass and high-pass filters, adjustable from 30Hz on the low end (the fundamental frequency of a low B) all the way up to 14kHz on the high end (about half an octave shy of the upper limit of human hearing). A high-pass filter passes frequencies above a specific point, and restricts those below that point, whereas a low-pass filter does the opposite. The high-pass filter on the 4 ON THE FLOOR is adjustable between 30Hz and 200Hz, which spans nearly subsonic territory, to well into the lower midrange. The low-pass governs the band between 1kHz and 14kHz; roughly the zone of bass string/fret articulation presence, up to shimmering, airy ultra-highs. 

One thing many bassists have long enjoyed doing with effects is to exclude their lowest fundamental frequencies from processing, to maintain a strong and clean foundation. This is where the high-pass comes in handy, perhaps set to about 100Hz (to my liking). And, as many bass players and amped acoustic guitarists know, distortion just doesn’t sound good through high frequency drivers, such as tweeters – and that’s where the low-pass filter comes in handy. Set to around 2kHz or so, you can effectively remove the distorted signal from your tweeters’ workload and keep all the distorted mojo happening through a larger, paper-cone speaker, where it often sounds best. But what about the sound you’re putting out below and above those selected filter points – don’t you want to hear that, too? Of course, and the 4-OTF has you covered – via its CLEAN VOL control. This parallel but separate signal path passes your input signal to the output via a boost/cut level control, so you are free to add in the amount you’d like to hear above and below the overdriven signal path’s cutoff points, with only the band-passed swath of frequencies that you’ve defined coming out dressed in satisfying saturation. 

Finally, the DRIVE SELECT control with its four selectable GEARs is located all the way to the operator’s right-hand side (just like it would be on any other classic American muscle machine), and offers distinctly different voicings for the overdrive path, generally increasing in compression and saturation from GEAR 1 through 4, with other subtle voicing changes along the way. GEAR 1 is designed to sound most like a tube amplifier under a medium load; still dynamically responsive, but a little gritty when you dig in; very much an envelope filter/voltage-controlled style of effect application, for those familiar with that kind of effect’s more common presentation (wherein the VC circuit opens up and moves around a bandpass EQ filter). By the time you get to GEAR 4, you’re closest to bass fuzz land, although not quite the kind you may have in mind if you’ve played through a Big Muff. This GEAR produces the most compression, for an almost synth-like response, and the thickest, symmetrical distortion (the lower 3 gears feature more amp-like asymmetrical clipping). With the DRIVE SENSITIVITY set to High and the DRIVE dimed with a high-output bass, you’re not going to be wanting for more distortion unless you’re playing in an industrial band!