This is the Genzler 4 On The Floor. You could say it's four drives in one. Or can you?
The control layout is somewhat unique: You get a switch that seems to act as an input pad to tame high output basses. Then you get a Gain knob and two volume knobs, one for clean and one for the dirt engine. The dirt engine has a four way toggle, ranging from the imitation of a tube amp's clean channel to full-on overdrive. In the top row, there are high- and low pass filters. The high pass is located before the clipping happens, while the low pass comes after the clipping stage. Both filters only affect the drive part of the signal and leave the clean signal as-is. You do not really get any tonal options here, but a lot of knobs to shape and fine tune the drive that's happening. By balancing dirt and clean signals and using the filters, you can dictate the frequency range in which overdrive happens and the frequency range in which it does not. With the low pass on the drive section, one should also be able to use the 4 On The Floor running directly into a PA system without the need of a cabinet simulation.
Printed on the enclosure, you'll find the words "Designed and Inspected in the U.S.A.", while a sticker on the bottom proclaims that it was made in Taiwan.
The chassis is not your standard Hammond 1590 format, but something Genzler came up with. Fit and finish remind me of the Strymon pedals, the execution certainly is nearly as flawless.
Also a bit unusual is the dual LED setup. One LED lights up when the pedal is in bypass, the other lights up when you engage it. Even though the bypass has an LED status, it is a hardwired true bypass. The pedal lights up as soon as power is connected, even with no audio cables connected - and there is no battery option.
Measuring Gears 1 through 4, I get the following graph:
This is with the filters wide open, the clean signal turned off and the Gain at noon.
Not much to report here. This looks fairly flat, with a slight accentuation around 400Hz. The fourth gear did a little less on the meter, which is probably due to heavier compression.
I found that unity on this pedal is not noon, but closer to 2 o'clock on both the drive side (with Gain at noon) and the clean side.
So what's the path to tackle this pedal? I try to walk myself through the thought process behind the pedal and how the makers might have envisioned the sophisticated bassist of today might go about setting it 'just right'.
First in line is the switch. I do treat it like any input pad switch on anything: Leave it on the sensitive setting and ignore it unless you run into problems that are a result of feeding the unit an input signal that's way too hot. My input signal is not, so ignore it is.
Drive and Drive Vol are a couple that will determine the output level of the drive part of the signal, Clean Vol is the single knob that determines ... you all are smart enough to figure that. Drive does work in conjunction of the gearbox, though.
At this point, I need to expand my horizon in the English language. I do assume that Jeff Genzler is, to say it with the presidential vocabulary, "A high-IQ person", because his designs in the amp world suggest that either he's a brilliant engineer or he can tell a normal engineer from a brilliant one and hired the latter. Why am I writing all this? Well, in my limited understanding of American English, the term "4 on the floor" refers to a drum beat, a 4/4 in which all four measures are played with the kick drum. An okay name for a pedal, but somewhat weird on a pedal that uses car-terminology. Lo and behold, there's another explanation, though. In automotive context, the late sixties and early seventies saw a relocation of the lever that shifts gears. The olden days, the cars had three forwards gears and the lever was mounted on the steering column, which was referred to as "Three on the tree". The new cars that came out found the lever mounted between the driver and passenger seat, on the floor, and guess what? They expanded the amount of forwards gears by one, to a total of four.
Americans did abandon manual transmission shortly after and never cared to update the term to modern cars, where 5 and 6 gears became the standard, because driving stick is for Europeans.
However, in the Genzler pedal, the 4 On The Floor surely refers to the automotive origin, with a tip of the hat towards the drum beat to connect the world of cars to the world of music. I'm no expert in cars, but I'm pretty sure I've heard the term overdrive used there, too.
Sadly, there's no little lever that can be cranked into position to select the gear the overdrive is in - it's done by a four way rotary switch. The switch travels easily and with not much friction, which feels surprisingly good. I would have thought that I strongly prefer a rotary encoder that snaps over with considerable force and comes to rest with a satisfying click, but this smooth operation totally works for me.
Let me quote the scripture:
1st GEAR: Reminiscent of a tube amp’s clean channel (including natural harmonics) with a bit of overdriven tone when driven hard. A nice “always-on” selection.
2nd GEAR: Emulates a tube amp’s mildly overdriven tone, with a small amount of dynamically compliant clipping asymmetry. This is a natural feeling, touch sensitive algorithm with very mild compression that responds with more texture and complexity, the harder you dig in.
3rd GEAR: A more aggressive up-shift from 2nd gear, this moderate, asymmetrical overdrive is less compliant, with greater compression for a tighter feel.
4th GEAR: This is the most aggressive gear of all — a heavier, symmetrical, low compliance overdrive that can enter distortion territory when driven hard. While there are a lot of harmonics and compression present, this gear does not give up tone or feel.
This sounds like this might actually be the place to start. Envisioning a tone, or the nature of the tone I'd like, I put the pedal in gear, and then use the Drive dial to set the RPM, then balance the drive and clean volume and listen to unwanted frequencies in the drive itself, so I can tackle them with the filters.
High pass goes from 30 to 200 Hz, while low pass goes from 14k to 1kHz. While the range of the low pass seems fine, I might have wanted the high pass to reach a bit higher than that - but that's still making assumptions without having played a lot.