Sweet Sixteen MkII 

MIDI / i2C / CV controller 

Tesseract Modular

This module is a eurorack version of the 16n Faderbank, implemented with 16 CV inputs and some other smart add ons. Almost everything is in the front panel.

There are 16 channels, which can be used as:

• Midi controller
• Manual CV generator (0 to 8v range)
• Attenuator
• CV to Midi CC
• i2C controller
• CV to i2C data

Features:

• Midi trs out
• Jumpers on the back to swap between ‘Arturia/Novation’  and ‘Korg/Makenoise’ Midi trs standards
• USB Midi out (usb midi class compliant device)
• 4 switches to enable bi-polar CV to Midi/i2C conversion (one for every 4 channels)
• i2C via mini jack on front panel and pin header on the back of the module.
• 16 inputs
• 16 outputs
• 16 faders
• 16 bi-color leds to show what’s going on in every channel

Specifications 

24 HP

+12V 92 mA

-12V 86 mA

Functions

The Midi CC number and channels can be different for the TRS jack and the USB port. The firmware has been tweaked to allow also Pitch Bend, which is pretty handy because you can get much better resolution through Midi (from min to max values Midi CCs have 128 steps and Pitch Bend has a resolution of 16.384 steps).

Midi CCs, midi channels, fader calibration and i2c master settings can be customized with the web editor.

The voltage generated by every fader is up to 8v, which is good enough to control eurorack modules (like wide open/close the cutoff frequency of a filter etc).

In the midi CC messages, 0 volts will correspond to a value of 0, and 8 volts to a value of 127. But the CV to Midi can handle also negative voltages, for such task there are 4 slide switches (1 for every 4 faders) that swaps the internal voltage reference in a way that, when activated,  0 volts will be the middle position of the midi controller, -4 volts the minimum value and +4 volts the maximum. Those switches only affect the Midi/i2C outs, CV outs won’t be affected by them in any way. 

If you plug in a bigger voltage source (like a -5v+5v LFO or a 10v envelope) the fader will work as attenuator, so you’ll be able to adapt how that signal affects the Midi CC out, covering the whole Midi CC range, saturating the waveform or just affecting it briefly.

Panel USB port is type B, which seems to be stronger than mini or micro ones.

i2C  could connect directly to  an ER-301, monome Ansible or a monome Teletype. 

The Teensy can be powered via the internal regulator or the +5v eurorack rail (selectable via a switch on the back).

The partial kit comes with all SMD populated, so only through hole components requires soldering work.

This new version is oriented for firmware tweaks and future expansions, still being fully compatible with the 16n and the previous Sweet Sixteen. 

Changes from previous versions:

• Function push button (for GESS presets)
• Function led
• Expansion header in the back
• i2C pull-up switchable with jumpers (aux pcb not required)
• Mate black & gold panel with brass nuts