Scott Stites KLEE 2 Sequencer
This page is dedicated to the KLEE2 i plan to build. It's a supercool project and there is even a set of PCBs available soon. Check out the electro-music forum for further information:
This project is still in progress so schematics and/or frontpanel design may be amended as long as you see this words! You can build it the way the current schematics suggest.
The following schematics are from scott stites revision 3 and offer different scaler and output options to choose from.
gate trigger bus
The Klee sequence really comes alive when one can distribute its control output in the same way its sequence is constructed. I've found that even a mundane sequence can come alive when the Klee distributes its events using a number of voices. This distribution relies solely on providing a means to send out gate and trigger signals derived from the Klee sequence itself.
The Klee2 design has three gate busses, and each bus actually will produce a trigger in addition to the gate signal The difference in effect, again, is that a 'normal' sequencer only has one stage active at any time. Of course, this does not apply to the Klee, and therein lies its change of behavior.
Another addition is the 'Merge' function. In short, the merge function will 'merge' two or more gates that are adjacent to each other on a bus into one unbroken gate. It will also produce one trigger for each 'merged' gate.
Let's look at the schematic. The first item to call attention to is the Clock Delay sub-circuit, as everything is actually produced from it. It produces a delayed version of the 'Clock' signal. This delayed version of the 'Clock' signal is called 'D_Clock'. All gates and triggers produced on the Gate Bus are derived from D_Clock by ANDing stages with it. If a stage is active, then that stage will produce a high when it is ANDed with D_Clock.
The heart of the gate bus is the switch/diode matrix in the center. Each switch is a SPDT On-Off-On switch. This means that these switches have a center position that disconnects either throw from the pole of the switch. The Stp n signals (Stp 1, Stp 2, etc.) originate from the Encoder circuit, which was covered in Episode 2. If you recall, a Stp signal goes high when the bit associated with that Stp is high. Each Stp n signal is assigned to its own bus switch through a diode.
Let's look at what happens when Stp 1 is high. If Switch 1, the bus switch STP 1 is dedicated to, is switched in the up position, it is switched to bus 1, and that high is fed onto bus 1. If Switch 1 is switched to the center position, the signal is fed onto bus 2. If Switch 1 is switched to the down position, the high on Stp 1 is fed to bus 3.
After all we have
1. Three Busses to distribute gate and trigger signals to different destinations at different points in the sequence.
2. A master output that generates a constant stream of gates and triggers in time with the input clock.
3. A method to individually manipulate the gate times and number of triggers on each of the bus outputs.
4. A method to truncate the number of steps a particular sequence will have.
The other enhancement concerns the merge function. If Merge is off, the pulse width of the clock controls the gate duration, which is a cool feature. If Merge is on, the gate width is fixed for as long as a step is high, or if the steps run together, for as long as those combined steps are high. A third option, one derived from the ARP1601, is to generate internal blanking pulses. This would allow the gates to be fixed for the length of time a step is high, but would prevent them from merging. So, longer fixed gates would be generated, and a trigger for each gate would be generated, regardless of if the active steps were adjacent or not.
As it sits, the three gate busses provide a huge panopoly of functionality if one thinks of it any time at all. Up to four devices can be controlled uniquely from one sequence. Even a single voice will gain the ability of 'accenting' certain steps in the sequence. For example, gate its EG with the Master Gate out and retrigger the EG with selected trigger outputs from one of the busses.
The examples illustrate the simplest use of the Merge-Function - using only one active bit in the register. Once more than one bit goes active - Klee function as opposed to 'normal' sequencer function - it gets quite varied.
Paul Klee:
Der Paukenspieler
scaler v1?scaler v2?scaler v3?
cv output v1gate bus?cv output v2
cv output v3
merge function off for both busses
one bit active in register
merge function on for both busses
one bit active in register
It will look like this.
his site...frontpanel designconstructionschematics
know the klee (manual)Glossary (mnemonic table)?schematics rev 3
Synth DIY
last update 16 SEP 08