WTF is a Benjolin?

This week’s patch will be a deep dive and exploration of the Benjolin, but the thing is, a Benjolin is … kinda confusing at first glance. So this week, we get a little bonus content in the form of a Benjolin explainer! If you already know what a Benjolin is/does, and/or you don’t care and you can accept “I turn the knobs and the sounds of legions of damned souls escaping hell in the midst of a UFO invasion erupts” as enough explanation of how the Benjolin works, you can skip this post. Otherwise, read on!

The Benjolin is quite an instrument, and yes, it is a full voice and a complete instrument all in itself (several standalone versions exist). It consists of two oscillators, a filter and its Very Special Sauce: the rungler. What is a rungler, you ask? Well, it’s a another analog shift register tool, of course!

If you recall in week three, when we introduced the theory and practice of generative sequencing, the shift register is the heart of a generative sequencer — it’s a kind of conveyor belt of voltages, with a bunch of “buckets” that contain a value sampled into the register. Then you have some rules to determine when the buckets get new info or if they stay the same, etc, and you output the bucket’s value when it reaches the end of the conveyor and voila, you are generating sequences!

In the Benjolin, oscillator one is the sample source. Oscillator two is the clock. At every clock pulse, the rungler decides whether to read/store the value of the triangle wave generated by oscillator one and advances one step. Values get rungled up (i.e. some logic is executed on the values stored and a value derived;it’s too mathy for me to care about) and spit out back to both oscillators and the filter, controlling frequency in all cases, at a level determined by individual rungler knobs. Oscillators also have a pitch CV input that is normalled to the opposite oscillators triangle wave output. That can be attenuated to zero, or overridden by plugging into the jack.

The filter is fed not by either oscillator, but by a pulse-width modulated square wave derived by a comparator looking at both oscillators. That feeds the filter, and there’s an external input that allows you to mix in another signal (including one of the oscillators directly, if you care to do it). Got all that? No? It’s a lot, but again, if you can’t follow it and just want to know what it does: I turn knobs, warblegarblegraaaaabrrrrrrrrrrrrZZZAAAAAAAAAAAAANG comes out. Hey look, here’s a link to an an all Benjolin song from my last album, maybe this will help?

If it isn’t apparent from reading that, the Benjolin is basically a big feedback loop. A signal is read from oscillator one, at a rate determined by oscillator (clock) two. A value derived from that then determines the frequency (i.e. speed/pitch) of those oscillators/clock. You can control how much of each signal goes where but it’s not something you can “play” in a traditional sense. Instead, you kind of interact with it, reacting to it as it reacts to you. It will fall into periodic states of near equilibrium for minutes at a time, then collapse into chaos in a second. It feels like a living, breathing thing — or maybe more like an otherworldly force, barely controlled by careful hexes and arcane sigils. Fun, though!

The filter is highly resonant and carefully tuned to work well with the crazy shit the Benjolin gets up to. It has its own rungler control, but doesn’t feedback into the system as a whole. It also has an external CV input and a knob for resonance — no cv control for that, alas. Other inputs allow to externally clock it (useful! but not as wild, thus not as much fun) and control some clock-related settings with gates.

Elsewise, the Benjolin has a bunch of outputs — pulse and triangle for both oscillators (useful for clocking external gear with the Benjolin — I usually clock my delays with it in patches based around it); an output for the pulse wave derived from the comparator; highpass, lowpass and bandpass filter outputs; an XOR output that can be used as a clock of sorts; and, perhaps most importantly, the rungler gets an output so you can rungle your other modules. There are a pair of expanders as well, one of which adds gates derived from the rungler (I have that one) and the other gives a stepped output, usable for pitch control or whatever else you like, derived from but different than the rungler. (Find out more/buy one from After Later Audio.)

And that’s it! Now you’re ready to check out this week’s patch… (COMING SOON)