I admit that I’m a bit gun shy when it comes to logic and overly math-y modules, but the Two Bits from Klavis—a dual-channel logic module in compact 5hp—makes it all better... Not (that’s a logic joke)! Actually, Two Bits has a fantastic feature set and is fun to learn logic on for the beginner or skeptic, with an excellent manual to dig into if you need it. It’s a real swiss-army knife of a module and offers a total of fifteen different logic functions—some even have CV control over the conditions.
The two channels are arranged vertically and have the same basic control layout: a function selection knob (and indicator LED—handy for knowing when you’ve selected a new function) above A and B inputs. Below that is the channel’s normal output and an inverted out. Between the top and bottom sections are buttons for chaining functionality and for accessing and editing some of the settings for various functions.
Both the top and bottom sections have the same three boolean logic functions of AND, OR, and XOR (with the inversions of these—NAND, NOR, and XNOR available on the inverted output), and each channel has a few unique functions. The top channel includes SR (Set and Reset), -A and B (Minus A and B), Alternate, and three variations on edge detection: Pulse on Rising Edge, on Falling Edge, and on Change.
Channel B’s unique functions include a gate merger (similar to the OR function but the output will be retriggered even if it is already active), a Vote function wherein the inputs have to be the same for the output to take that value (and can be used with the chained 3rd input from channel A). Channel B also has four functions that accept CV control over some of their conditions (Channel B’s second input is also used for CV input). A Random function determines by chance whether to allow a signal at the Channel 2 input through (when detecting a rising edge on that same input). The random percentage can be set from 1 to 99 and adjusted via the CV input in real time. There is a pulse Delay Line, an analog Comparator, and a clock divider / multiplier with realtime CV control over the division / multiplication ratio as well.
The Set and Reset is a pretty handy toggle output, where the inputs A and B set and reset the output respectively. So a rising edge into A will send a positive (gate on signal) to Out A and a rising edge on B will close (gate off) Out A. Feeding two disparate signals into the A and B inputs, I found a lot of fun to be had with the toggle output used as a semi-random gater to open up a VCA in a less predictable, but not totally random way. I also found immediate uses in my patches for the different edge detection options available in Channel A, particularly to trigger different envelopes on key up events (falling edge) from my Intellijel Tetrapad Gate Out or both Key Down and Up. You can get even deeper into logic madness by feeding the outputs to one or both of the Channel B inputs. Combine them in the Gater function and run those pulses out to even more VCAs.
The fact that the functions can be triggered by any signal, not just pulses and gates, is great for experimenting with all sorts of input signal types. Half the fun is putting different waveforms in and seeing what comes out. Sometimes it’s noise, but you can stumble into all sorts of interesting rhythms, pseudo-random pulse streams, and other goodness, and it’s always good to remember that one man’s garbage noise is another man's treasure melody.
Before playing around with the Two Bits, I definitely underrated utilizing logic for making interesting things happen in a patch. I still haven’t come close to wrapping my head around all the different patching possibilities present its various functions, and I could read the logic truth tables until my ears bleed but that doesn’t mean that I could tell you what the response would be when I plug a sample of a birdsong on one side and a sawtooth wave on the other, but overall the Two Bits is pretty easy to use and damn fun.

5 HP +12v 31mA -12v 1mA
Price: $149

klavis.com