The Great Korg Minilogue OS 1.04 Bug Thread

UPDATE, Summer 2016: OS Version 1.21



1.21 has been released. It added a Latch to the arpeggiator.



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1. Steppy Filter

Although the controls for most parameters are 10 bit (1024 values), it's possible to hear discrete steps when turning the filter cutoff control, especially with self-oscillation. Cutoff spans a massive frequency range and even 10 bits worth of increments are spread a little thin.



Other synths have digitally controlled analog filters which feature slewed or interpolated control for smooth cutoff changes, including Novation's Bass Station II (only 256 steps but 100% smooth cutoff tweaks) and Roland's JD-Xi which launched with a steppy filter, and later updated via firmware to improve control interpolation. I believe it's possible to improve the cutoff control on the Minilogue, and that an analog filter should glide smoothly when tweaked.





2. Highpass Filter Inactive Range

The Minilogue's delay section includes a handy non-resonant highpass filter. It's controlled by a cutoff knob. It also has a big inactive range. When it finally kicks in around value 335, it produces a thump which makes the oscilloscope's flatline jump. It also causes zipper noise as each step is a large amount of highpass, as if it was "catching up" to where it should be at 11-o'-clock on the knob. Hopefully this control can be re-calibrated via firmware.



See the dead zone in action here:







3. Delay Time Value Jumps

The time knob on the Minilogue's delay has a large jump around above a speed of 45 (turning to the left), with each step in this range up to minimum time producing a large stepped pitch effect. In the steppy filter sound demo above, it is the third clip. The increments starting around a time of 50 and heading up to the right towards maximum time produce no noticeable stepping. The entire range should enjoy this smoothness. The time could also benefit from a higher top speed.





Other Quirks:



Leave a sync cable plugged in and it will detect the cable even if the other device is off. Tempo will freeze, causing BPM divided effects to not work. (Delay Voice Mode, Sequencer, etc.) Delay voice mode will also get a mono-retrigger bug if the tempo fails.



Arpeggiator and LFO will drift and are easy to confuse with external tempo changes. Whereas, the sequencer locks to incoming clock and stays solidly locked.



Filter tracking amount will occasionally get stuck on zero despite switch position, when legato notes or tied sequence notes are played.



Audio In Resonance: Using external audio will cause multiple voices to have maximum resonance despite the knob position. Manually tuning (shift + rec) seems to tame this behavior.



A global setting of Audio Input = Off will still pass external sound at startup. Switching the menu setting to On then Off again will mute the audio.