OB-1 0.6

OB-1 0.6 adds Digitone mk1 / Digitone Keys support, contributed by x2k77m1, alongside the existing Digitakt mk1 machine.

What's new

• OB-1 on Digitone mk1 / Keys, OS 1.44. Two VCOs with saw/pulse waveforms and sub-octaves, hard sync, cross modulation and noise feed the Digitone's own filter, AMP envelope, mixer and effects.
• Fifteen controls across two SYN pages. SYN1 provides mixer/routing; SYN2 provides independent coarse/fine tuning, waveform family and shape for both oscillators. Custom page graphics, parameter locks, MIDI CCs and LFO modulation are supported. FUNC+turn restores OB-1 defaults or a held step's lock.
• Mono playing on each Digitone track. New notes take priority, with a retained pair of oscillators and a short handover crossfade. Releasing the newest note returns to the newest held note while its stock voice remains available.
• Both device packages are version 0.6. The Digitakt sound engine and control layout are unchanged from 0.5.

Downloads and installation

Download	Device	Required stock OS	Required companion mods
ob1-0.6-os1.54.elemod	Digitakt mk1	1.54	Core and machine-pages
ob1-dn-0.6.elemod	Digitone mk1 / Keys	1.44	Core for Digitone and machines

Use Elekloader to combine the package and companion mods with your own matching stock OS. These downloads are mod packages, not complete firmware images. Digitakt OS 1.53 packages are not included in this release.

On Digitone, reselect OB-1 after updating from a development build; sounds saved with earlier development control maps may need their controls reassigned. Digitakt 0.5 sounds retain their parameter meanings.

Known limits

• Leave Digitone voices dynamically allocated for held-note return. Locking a track to one voice, or having an earlier note's voice stolen, can prevent return to that note.
• Releasing several held Digitone notes together can shorten the release tail depending on voice allocation. A fix is deferred to a follow-up.
• Digitone turn popups and LFO destination lists retain the borrowed FM parameter names.

Verification

Both packages passed stock-firmware lint/link checks, and both complete firmware images were built and verified locally. The host suite passed, including 49 regression tests and 42 Digitone adapter checks. Compiled Digitakt OS 1.54 firmware MIDI checks passed for all fifteen controls, defaults, note on/off, channel isolation and CC 9 reset. The DSP reference comparison remains at 307/311 passing, with the four documented XMOD mismatches unchanged.

Hosted CI is not green: its firmware build lacks the local Digitone OS 1.44 input, and the reference step reports the same four XMOD mismatches. The successful firmware builds and MIDI check above were run locally.

No fresh physical-device testing was performed for 0.6. The Digitone port's contributor-reported hardware checks are recorded in the support PR.

Full changelog: ob1-v0.5...ob1-v0.6

OB-1 0.5

User-visible changes since ob1-v0.4.

Controls and playing

• Two SRC pages with fifteen controls. Press SRC to switch between oscillator controls and mixer/routing. Each oscillator has its own row on the first page.
• Independent coarse and fine tuning. Tune each oscillator relative to the played note, from −32 to +31 semitones, with an additional −50 to +50 cents of fine tuning.
• Separate waveform family and shape. Choose SAW or PULS with TYP1/TYP2, then sweep WAV1/WAV2 within that family without accidentally switching between saw and pulse.
• Separate mixer and routing controls. Each oscillator's fundamental and sub-octave now has its own OFF / −3 dB / ON control. SYNC and XMOD have independent switches. Mixer levels appear as vertical three-position switches, and waveform previews follow the selected family and shape, including held-step locks.
• MIDI access to all fifteen SRC controls. CC 16–30 cover both pages, including the separate mixer, sync and cross-modulation controls.
• MIDI voice reset. CC 9, with any value, resets the addressed OB-1 track's oscillator and noise state without changing its sound settings. It does not retrigger the track's amp envelope or reset filters/effects; resetting a sounding voice can click.

Sound

• Continuous oscillators while a note is active. Muting an oscillator's output no longer freezes its phase or disables selected sync/cross-modulation paths. Bringing it back into the mix preserves its ongoing phase. Fully silent voices can still pause.
• More accurate tuning, especially in the low register. Improved pitch precision follows standard A4 = 440 Hz tuning.
• Revised upper-register response and noise balance. High-pitched oscillator output becomes progressively quieter, the output has a gentler high-frequency response, and noise level/spectrum more closely follows the reference plugin. This is a partial reference match, not a claim of complete hardware or plugin fidelity.
• A slightly detuned init patch. Newly selected OB-1 machines start with FIN2 at +2.4 cents to keep unison phase cancellation moving. Set FIN2 to +0.0 for exact unison. Loaded sounds retain their stored tuning.

Compatibility

The new parameter layout is a breaking change: older OB-1 sounds, parameter locks and LFO assignments are not migrated and need to be recreated or reassigned. Newly saved sounds use the version-4 sound format and require compatible custom firmware to reload.

OB-1 0.4

What’s improved in 0.4

• Held-note recall: Releasing the newest note returns to the previous note still held, with its original velocity.
• Closer oscillator sound: Improved triangle-to-saw shapes, more consistent waveform levels, and recalibrated cross modulation and noise against the reference VST.
• Correct −3 dB mixer settings: Middle mixer positions now deliver the intended attenuation.
• Cleaner output: Reduced overall level by 10 dB to prevent clipping when combining oscillators, subs and noise.
• Fixed high-note tracking: Notes continue above C6 instead of becoming stuck at the same pitch, up to the existing 12 kHz ceiling.
• More reliable sync and modulation: Fixed BOTH-mode routing when a muted oscillator still feeds cross modulation, plus a pulse-edge overflow.
• Lower CPU usage: In the tested heavy simulator workload, modeled CPU load fell from 98.8% to 92.3%.

Built for Digitakt mk1 OS 1.53 and 1.54. Performance figures are simulator measurements; physical hardware qualification remains outstanding.

Full changelog

OB-1 0.3

Full Changelog: ob1-v0.2...ob1-v0.3

OB-1 0.2

Full Changelog: ob1-v0.1...ob1-v0.2

OB-1 0.1

Full Changelog: https://github.com/simonjohansson/elektrob-1/commits/ob1-v0.1