After a succession of betas we are finally ready for a new mainline release. A host of improvements, fixes and additions makes the SB01 better than ever!

Leading up to the manufacturing of the second batch of SB01s we wanted to bring something new to the instrument celebrating the milestone.

Some of you might have noticed the REC label on the front panel. Up until now this shift layer function has been left unused. We wanted to rectify that and finalize what was intended.
REC is now a real-time sequence editor. After loading a sequence, SHIFT+REC can be pressed to enter live edit mode. When in this mode the sequence will play, and the events can be modified by holding a key, LEGATO+key or REST when the clock ticks.

Live edit mode brings a fun and immediate way of interacting with sequences — great for changing things up while performing.

Getting user feedback is fantastic, especially when we can help someone realize their goals by adding something or changing something for the better.

We have gotten a few requests this past year, and it has been extremely good fun to work on your specific problems as apposed to problems we make up for ourselves.

The highlights of such user collaborations are:

• MIDI note offset configuration (for working with gear with unconventional MIDI note translation)
• TRS MIDI soft-thru (for easier MIDI patching)
• USB MIDI soft-thru (use the SB01 as USB MIDI interface)
• On-device configuration menu (For configuring MIDI etc. when in the field without a computer)

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

- On-device configuration (See new addition to the manual for instructions).
- Ability to set MIDI note output offsets for both internal and external channels. This is useful when working with gear that does not follow the A4 = 440 Hz MIDI norm. Settings can be reached via the on-device configuration menu or the control panel app.
- Added TRS MIDI in to TRS MIDI out soft-thru. Disabled by default. Can be configured in the control app. Useful when daisy-chaining devices.
- Added USB MIDI in to TRS MIDI out soft-thru. Disabled by default. Can be configured in the control app. Useful when needing the SB01 to act as a USB MIDI interface.
- Added LED feedback when entering legato and rest events.
- Made `PORTAMENTO` channel independent. This way you can have portamento on for one channel and off for the other. The drawback is that the `PORTAMENTO` toggle switch is not always in sync with the actual portamento state of each channel. We feel this is an acceptable trade-off for the added flexibility.
- Added MIDI input vibrato toggle support. Vibrato is handled through MIDI CC21 messages on the `INTERNAL` channel. A value of 0-63 turns vibrato off, and a value of 64-127 turns vibrato on.
- Added support for more complex USB devices in USB host mode.
- Added MIDI output when in USB host mode. The SB01 can now control connected USB MIDI devices.
- Added sequencer `REC` mode. By pressing `SHIFT` + `REC`, a loaded sequence can be live edited. (See new manual entry for details).


### Fixes

- Fixed issue where the sequencer corner playback mode could go out of bounds and stop/corrupt the active sequence.
- Fixed issue where a note would hang if key on/off action was made close to or under 1ms apart when in `GATE + TRIG` `ENV` mode.
- Fixed issue where chain was not applied before releasing chain button.
- Fixed issue where battery measurement animation was blinking.
- Fixed issue where the arpeggiator didn't affect the `INTERNAL` channel in `BOTH` mode.
- Fixed issue where USB MIDI input would cause intermitheard glitches mostly heard as double triggering of notes.
- Fixed issue where `Caterpillar` down arpeggiator mode sometimes played an unwanted low note.
- Fixed issue where `Corner` sequencer mode stopped the sequence.
- Fixed issue where `Caterpillar` up/down sequencer mode created identical results.
- Fixed prevaling issue where USB MIDI input would cause intermittent glitches mostly heard as double triggering of notes. This was ultimatly caused by interrupt priority conflicts. The previous fix was proved insufficient at high MIDI input rates.
- Fixed issue where `HOLD` did not work correctly in `PLAY` mode.
- Fixed issue when pressing `HOLD` in `PLAY` mode while at a rest step caused the sequencer to mute until `HOLD` was toggled off.
- Fixed issue where legato notes where not handled correctly in `PLAY` mode.
- Fixed issue where portamento `ON` was not applied correctly in `PLAY` mode.
- Fixed issue where changing to any arpeggiator mode from `PLAY` mode did nothing.
- Fixed handling of mode changes in `BOTH` mode.
- Fixed accidental breakage of arpeggiator in previous release.
- Fixed issue where `LOAD` reset sequencer when no editing was done. Sequencer should only reset if an edit was made.
- Fixes issue where keys eventually got stuck when playing many notes while `HOLD` was active.
- Added missing `TRANSPOSE` `LATCH` mode (SHIFT + TRANSPOSE).
- Fixed issue where last played note was not released via MIDI when jumping to another sequence.
- Fixed issue where external trigger output was stuck high.
- Fixed issue where external channel arpeggiator would reset the LFO when entering `ARPEGGIATOR` mode when the internal channel had arpeggiator active causing unwanted pause.
- Fixes issue where tuning was not applied to the external channel when editing in the control app.
- Fixed developers sense of humor.
- Fixed issue where `HOLD` was not properly reset when entering sequencer `LOAD` mode.
- Fixed issue where changing channel would sometimes disrupt the gate on running sequences.
- Fixed issue where a sequence could not begin with one or more rest events.
- Fixed issue where LFO was not reset when key was pressed in `LFO` envelope mode.
- Fixed issue where activating arpeggiator without keys held would reset the LFO.
- Fixed issue where pressing the `CHAIN` button reset playing sequence.
- Fixed issue where chain was never reset.
- Fixed issue where new chain did not wait for current sequence to finish before starting.
- Fixed issue where reconnecting USB devices in USB host mode caused MIDI transmition and reception to stop.
- Reintegrated missing CDC API end-points (internal tooling issue, users not affected)
- Fixed issue where USB4/Thunderbolt cable connected to the SB01 and not connected to anything at the other end would affect LFO/clock stability.

### Changes

- Changed the algorithm governing received MIDI start/continue/stop messages. The instrument remembers if sequencer or arpeggiator was last active, and starts/stops the last active mode – defaulting to sequencer if no last active mode detected.
- Prevent chaining to empty sequences.

↳ Rune and Ben

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