#434 krell
Building the Boldport Krell - a handheld DSP synthesiser built around a Microchip dsPIC and a design from madlab.
Here’s a quick demo..
Notes
Krell is a handheld DSP synthesiser. Buttons and potentiometers dial up a range of sounds. The Boldport project is a remix of a soldering project by James Hutchby of MadLab.
At the core of the circuit is a Microchip dsPIC33EP128MC202-I/SP. It’s an interesting choice - a digital signal controller that is really designed for precision motor control, now put in service of creating music (or at least weird sounds).
Kit
| Qty | Description |
|---|---|
| x1 | dsPIC microntroller, Microchip dsPIC33EP128MC202-I/SP |
| x1 | 3.3V Regulator, TI LP2950-33LPRE3 |
| x1 | NPN bipolar transistor, ON BC547CTFR |
| x1 | 220μF electrolytic capacitor, Multicomp MCUMR6V3227M6.3X5 |
| x2 | 10μF electrolytic capacitor, Multicomp MCUMR16V106M4X5 |
| x1 | 10μF tantalum capacitor, Suntan TS19001C100MSB0A0R |
| x3 | 100nF capacitor, Suntan TS170R1H104MSBFB0R |
| x6 | 47KΩ trimmer, Piher PT10MV10473A2020-I-PM-S |
| x6 | Black thumbwheel, Piher 5034 |
| x4 | White LED, Valcon VDIFFLED-3mm-W |
| x2 | 100Ω resistor, Multicomp MCF 0.25W 100R |
| x1 | 1KΩ resistor, Multicomp MCF 0.25W 1K |
| x6 | 10KΩ resistor, Multicomp MCF 0.25W 10K |
| x1 | Battery holder, TruPower BH 431-1P |
| x1 | 3.5mm stereo jack socket, TruConnect 20-0137 |
| x1 | 28-pin DIP socket, TruConnect 22-0114 |
| x1 | DPDT slide switch, C&K JS202011SCQN |
| x1 | Button sheet, Snaptron Peel-N-Place™ |
| x1 | PCB |
Circuit
My quick re-draw of the circuit..
Construction
It’s a nice simple build this time for just an iron and my favourite 2% Ag solder.
The Snaptron buttons are an interesting construction variation: they come preset with clear adhesive strip. With careful alignment, all buttons stick in place with no soldering required. I can see this being super efficient for small batch assembly.
The finished noise maker..
Credits and References
- Krell - product page
- Krell - Boldport store
- Krell source code
- dsPIC33EP128MC202 product info
- ..as mentioned on my blog