Buchla - 252e Polyphonic Rhythm Generator

The 252e Polyphonic Rhythm Generator is a polyphonic sequencer specialized in polyrhythms and polymetry. The sequencer works with cells contained in eleven concentric rings. Three of these rings can be played simultaneously. Three pulse outputs and six CV outputs can be freely assigned to the cells. If required, one cell can generate up to seven trigger pulses, which can be time-weighted and applied to a separate sub-division output.

The 252e works with cells located within eleven concentrically arranged rings. Each ring can contain a different number of cells, from three cells to 16 cells. The sequencer generates three clock signals, each of which can be assigned to one of the rings. This means that a maximum of three of the eleven rings can be "played". The assignment of the clocks to the rings can be done manually as well as by CV.

Three pulse outputs and six CV outputs can be freely assigned to each cell and also in combination. The programming of the cells, and thus also the assignment of the outputs, takes place on several levels. Although this sounds complicated, the operation is extremely intuitive. With the "Cell" Encoder you can navigate freely through the cells during programming. The adjacent "beats/cycl" encoder allows you to change between the rings.

If you are in the "pulses" section and press the (red) button titled "red", a pulse trigger at trigger output 1 (red LED) is generated at the position of the selected cell. If the green or blue button is also pressed or instead, a trigger is generated alternatively or additionally at pulse output 2 (green LED) or 3 (blue LED). Cells with programmed pulses are displayed in color (possibly as color mixing) within the ring. For each individual pulse, the length of the pulse signal can be adjusted from short transients to the maximum time the cell is played. With the parameter "behind/ahead" the cell can be moved forward or backward in time. By subdivide it is possible to divide the cell into up to seven further segments. This so-called subdivision does not influence the actual pulse outputs, but is connected to its own subdivision output. The subdivision of the cell does not have to be linear. The weighting can be adjusted with the encoder.

If you are in the "cv 1-3" level, you can use the "Select" switch in the CV-edit section to select the CV-outputs 1-3 and program a voltage between 0 and 10V. This control is quantized to 0.1V, which corresponds to a semitone in the 1.2V/octave standard. By pressing the encoder it is also possible to make changes in the cent (a semitone is 100 cents) range. A cell does not necessarily have to contain CV information. It is possible to keep the last defined voltage at the CV output. The level "cv 4-6" behaves analogous to "cv 1-3", but here the CV outputs 4-6 are being controlled. The display level called "subdiv" is only used for an overview of cells containing subdivisions. However, it is not a programming level of its own.

A "phase" titled encoder can move all cells in a ring back and forth. Since CVs and pulses are separate within the 252e concept, they can also be moved separately, depending on the display mode selected. The "Copy" and "Paste" buttons can be used to quickly copy cell information. It is not necessary to copy the complete cell. Here, too, the display level determines which data is actually inserted. It is also possible to create random pulses or CV-patterns on a ring using different key combinations. Alternatively, the cells can also be "filled" with Euclidean patterns.

In the Clock section you assign each of the three clocks to one of the rings. This is also where the master BPM is set and the sync behavior is selected.

Sync mode "on 1" means that all rings need exactly the same time until they are repeated. The time each ring takes is independent of the cells, making it easy to create interesting polymetric structures.

If the sync mode "on cycle" is selected, each cell jumps to the next cell per clock tick of the master clock. The time each ring takes to play is now dependent on the number of cells. In this mode you can easily create interesting polyrhythms, whose phase position can be easily seen in the circular display.

The three pulse and six C- outputs can of course be used at will, but can also address the three parameters "Note On" (Pulse 1-3), "Pitch" (CV1-3) and "Velocity" (CV4-6) within a complete voice. Following from this it is possible to program the cells with a MIDI keyboard via the MIDI implementation. In this mode the CV-level works differently and the selection, via the "select" switch, is made in the CV pairs 1+4, 2+5 and 3+6 as pitch and velocity pairs.

The sequencer can create its own MIDI clock or synchronize itself to an incoming MIDI clock.

All parameters can be saved and recalled in conjunction with the preset manager of the 206e or 225e modules.

Please note: Buchla 200e products may have lengthy waiting times, as they are manufactured in small quantities only.