

Module
Quantizer, arpeggiator, and string synthesizer in a single module.
- Size
- 98.2 × 109.2 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 64
- Nets
- 80
- Pads
- 258
- Tracks, vias
- 582, 62
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 1 Jan 2024
- Updated
- 21 Apr 2026
Overview
Module is an open-source printed circuit board by zlosynth, from the zlosynth/arplus repository on GitHub, published under the CC-BY-SA-4.0 licence. It is a 2-layer board of 98.2 × 109.2 mm with 64 parts on 80 nets, routed with 582 tracks and 62 vias.
It is built around the 74HC595 and B10K. Its parts include 15 resistors, 13 connectors, 10 diodes, 7 switches and 4 capacitors. It belongs with the audio and music boards and the STM32 boards of this library.
Main components
2README
README.mdArplus
Quantizer, arpeggiator, and string synthesizer in a single module.
- Karplus-Strong string synthesis with 6-voice polyphony
- External audio input for custom excitation sources
- 31 different scales and chords of up to 8 notes
- Configurable scales
- CV-controllable arpeggiator patterns
- Quantized 1V/oct output
- Three different stereo output modes
- Based around Electro-Smith's Daisy Patch SM platform
- Programmed in Rust
Find more details about the module, including a feature overview video and a user manual, on its website.
License
Software of Kaseta is distributed under the terms of the General Public License version 3. See LICENSE-SOFTWARE for details.
Schematics and PCB layout are distributed under the terms of Creative Commons BY-SA. See LICENSE-HARDWARE for details.
The manual is also distributed under the terms of Creative Commons BY-SA. See LICENSE-MANUAL for details.
Derivative work
This project is open-source. As long as you comply with the license, you're free to study the code, copy it, modify it, build your own module, and even sell it.
However, if you choose to sell your own build, please do not use the name "Zlosynth" on the panel, and clearly state in the description that it is a clone.
Changelog
Read the CHANGELOG.md to learn about changes introduced in each release.
Versioning
See VERSIONING.md to find detailed information about versioning of the project and compatability between its software and hardware.
Development
See DEVELOPMENT.md to find some basic commands to interact with the project. To learn more, read the code. A good place to start would be firmware/src/main.rs.
Parts
64| Qty | Value | Footprint | References |
|---|---|---|---|
| 15 | 1k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R1, R2, R3, R4, R5, R6, R7, R8, R9, R22, R23, R24, R25, R26, R27 |
| 6 | B10k | BetterFootprints:Potentiometer_Trimmer_SongHuei | RV3, RV4, RV7, RV8, RV9, RV10 |
| 4 | B10k | BetterFootprints:Potentiometer_Alpha | RV1, RV2, RV5, RV6 |
| 2 | 100n | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C4, C12 |
| 2 | 10u | Capacitor_SMD:CP_Elec_5x5.8 | C1, C2 |
| 2 | CV5 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J10, J11 |
| 2 | D_Schottky_Small | Diode_SMD:D_SOD-123 | D9, D10 |
| 2 | FB | Inductor_SMD:L_0805_2012Metric_Pad1.05x1.20mm_HandSolder | FB1, FB2 |
| 1 | 4051 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U5 |
| 1 | 74HC595 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U1 |
| 1 | BUTTON_1 | Button_Switch_THT:SW_PUSH_6mm | SW1 |
| 1 | BUTTON_2 | Button_Switch_THT:SW_PUSH_6mm | SW3 |
| 1 | BUTTON_3 | Button_Switch_THT:SW_PUSH_6mm | SW4 |
| 1 | BUTTON_4 | Button_Switch_THT:SW_PUSH_6mm | SW5 |
| 1 | BUTTON_5 | Button_Switch_THT:SW_PUSH_6mm | SW6 |
| 1 | BUTTON_6 | Button_Switch_THT:SW_PUSH_6mm | SW7 |
| 1 | BUTTON_7 | Button_Switch_THT:SW_PUSH_6mm | SW8 |
| 1 | CV1 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J6 |
| 1 | CV2 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J7 |
| 1 | CV3 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J8 |
| 1 | CV4 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J9 |
| 1 | CV_OUT | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J13 |
| 1 | Daisy_Patch_SM | BetterFootprints:DaisySM_4_Connfly | U2 |
| 1 | GATE_1 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J12 |
| 1 | GATE_2 | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J14 |
| 1 | IN | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J3 |
| 1 | LED1 | LED_THT:LED_D3.0mm | D1 |
| 1 | LED2 | LED_THT:LED_D3.0mm | D2 |
| 1 | LED3 | LED_THT:LED_D3.0mm | D3 |
| 1 | LED4 | LED_THT:LED_D3.0mm | D4 |
| 1 | LED5 | LED_THT:LED_D3.0mm | D5 |
| 1 | LED6 | LED_THT:LED_D3.0mm | D6 |
| 1 | LED7 | LED_THT:LED_D3.0mm | D7 |
| 1 | LED8 | LED_THT:LED_D3.0mm | D8 |
| 1 | LEFT | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J4 |
| 1 | POWER | BetterFootprints:Power_Connector_Connfly | J1 |
| 1 | RIGHT | Connector_Audio:Jack_3.5mm_QingPu_WQP-PJ398SM_Vertical_CircularHoles | J5 |
Questions
How big is the Module PCB?
It measures 98.2 × 109.2 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Module use?
64 parts, built around the 74HC595 and B10K. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Module KiCad files?
From the zlosynth/arplus repository on GitHub, at the commit this page was made from: the board is hardware/Module.kicad_pcb and its schematic hardware/Module.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Module design in my own project?
Its repository publishes it under the CC-BY-SA-4.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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