Since the initial release of the SB01 we have rewritten the firmware from the ground up to provide class-leading MIDI performance and major new features.
The top most priority has been MIDI — both latency and stability. Although MIDI is considered old technology it's far from easy to get right, especially on modern systems where so many things compete for resources. Due to unfortunate technology debt suffered early on in the project and sub par frameworks from the microcontroller manufacturer; we were left with no other choice but to do a complete redesign. The result is a beautiful piece of software architecture several thousand lines of code less than the previous implementation. The resulting MIDI performance speaks for itself – USB MIDI latency is now as low as 30µs. TRS MIDI is only limited by baudrate, which makes it as good as it gets. We are very proud of this. It has been hard work getting to this point, but the result is most definitely worth the countless hours spent on it.
Having buttoned up MIDI, we could focus on new and previously planned features.
First, we felt a simplification of the control app was in order.
The old matrix UI for MIDI routing was removed in favor of a simpler approach.
Tuning tables was next.
Since the very start of the project we have been dreaming of being able to play with alternative tunings, so next up was designing an interface for this. What we ended up with is in our opinion beautifully simple. You can set an offset (in cents) for every note, upload .tun tuning table files or choose from presets. Tuning is applied in real-time and makes it fun to experiment with alternative tunings.
After making an experimental section in the control app for tuning tables, we could also move an easter egg function to the front — it's called 32' Range and it simply lowers the instrument pitch by an octave so you can access the most bone shakingly deep notes the VCO can produce.
One of the most inspiring things to play with on a synthesizer is the arpeggiator. Having covered the basics with up, up/down, down and random modes, we set out to design a few more. The first is called Corner mode, where the first and last note is repeated twice. Sounds simple but it really adds just the right amount of perceived complexity. Last but not least are Caterpillar up and Caterpillar down modes — both extremely musical, and something we haven't seen on any other instrument.
These new arpeggiator modes are also available as directions for the internal sequencer.
The firmware redesign opened the door for additional MIDI event handling. We added pitch bend support, as well as mod wheel support. Mod wheel controls MOD CV, and can be used to modulate filter cutoff. This is exciting news for those who automate via MIDI.
Finally some quality of life improvements was added. Small things like animating the battery status LEDs, LED feedback on sequence saving, being able to set the instrument back to factory settings and the ability to see what firmware version is currently on the device in the control app.
The control app will also tell you when a new firmware version is available.
To upgrade, connect your SB01 to your computer and power on while holding the SHIFT button. Follow the instructions on screen or navigate to firmware.playsuperlative.com.
Here is the complete change log:
### Improvements
- Total firmware rework for improved MIDI performance.
- MIDI input pitch bend support.
- MIDI input mod wheel support. Incoming mod wheel messages to the `INTERNAL` channel will control the same CV as the `MOD CV` input. This can be used to control the filter.
- MIDI song selection support to load sequencer patterns.
- New arpeggiator `Caterpillar` up/down modes.
- New arpeggiator `Corner` mode.
- New `Chord` mode (MIDI output).
- New `Reset` function for sequencer.
- LED feedback when saving sequence. `INTERNAL` and `EXTERNAL` LEDs will blink once when saving is complete. Saving will never fail. This feedback is just to explicity inform the user that saving is done.
- MIDI play/continue events now resets the tick counter and only starts the sequencer if in `PLAY` mode. If in `ARPEGGIATOR` mode, the arpeggiator will do an immediate step. This way the sequencer and arpeggiator can be started in sync with other gear.
- User configuration can now be reset to factory defaults by holding both `MEMORY` buttons (`JUMP` + `CHAIN`) while powering on the device.
- Added tuning table support. You can now tune each key individually in the control app.
- Added user slot for custom tuning table. If the first key on the keyboard is held at startup the custom tuning table will be loaded. The custom tuning table can be edited in the control app. If no key is held at startup the default tuning table will be loaded.
- Added loading of `.tun` tuning table files in the control app.
- Added tuning table presets in the control app.
- Added `32' Range` toggle to user configuration. When enabled it sets `RANGE` to span 32' - 4' instead of the normal 16' - 2', which lets you go way deep.
- Firmware version display in control panel and firmware update app.
- Changing settings in control panel now has instant effect. Save is only needed to make changes permanent.
### Fixes
- Fixed MIDI latency issues. Latency should be ~30µs - ~1ms.
- Fixed limited MIDI note mapping.
- Fixed intermittent double note triggering MIDI issue.
- Fixed issue where a sequence could not begin with one or more rest events.
### Changes
- Removed unused USB MIDI port.
- Revised configuration system with simplified MIDI options.
- Prevent jumping or chaining to empty sequences.
↳ Rune and Ben