Hey all, I’ve been a bit out the synth world lately. Just got round to making a buss board for case 2.
Tested. Working, and looking forward to making more stuff =D
Got some oddness happening with the 8-step tho…
It’s set to a clock signal of 30 BPM from the BSP but it’s wayyyyy faster. Anyone know what could be going on?
It’s analog outputs modded version.
Speeding off on one of my baby8s was a bad earth connection causing a sudden surge when triggered.
A bit too short for Kosmo format, but I had a couple of these wine boxes and decided to give them a stain and use them for a smaller system that can be used for testing and hauling smaller modules around. I got the +/-12V AC wall-wart-based power supply PCB printed on a design by Arthur Saunier, and I built on stripboard a +9V DC wall-wart-based power supply based on a design by Jack Orman. I will eventually add to the stripboard busboard different power headers as needed.
Is that the BSP gate output into the sequencer?
Does it trigger anything else at the expected rate?
It’s the clock out from the BSP, it’s been used from the 1-8 outs before and runs at a normal (expected rate)
The KEYSTEP supports 5 different Analog clock rates:
- 1 STEP GATE
- 1 STEP CLOCK
- 1 PULSE (KORG)
- 24 PPQ*(Pulses per quarter note)*
- 48 PPQ
(That’s KeyStep, not KSP, but I would assume KSP is similar.) I bet yours is set to 24 PPQ. For this you’d want (I think) 1 STEP GATE.
Finally completed one of my Benjolins. I self etched two of the boards, finished building them and they just kind of sat around for a while. I went ahead and made a 3D printed case and laser cut top. I added the daughter board to amplify the filtered output because it is quite low.
A quick demo of my current project - an RP2040-based drum sample player, using CircuitPython. I’ve just got the jacks connected and needed to test them before going further…
Audio is 16-bit, 44.1KHz mono, using a PCM5102A board. I’ve got a few bits to build before I can consider the hardware finished - I need a gain stage for Eurorack levels, an analogue input protection circuit for a CV in and to assemble the power circuitry (7805 etc).
I finally got to spend some time putting my little CV keyboard circuit on the breadboard. It’s based on the “CGS10 Pedal board/Mini keyboard”, and by “based on” I mean it’s exactly his circuit (Ken Stone's Modular Synthesizer). I just re-drew the circuit onto a solderable breadboard.
I haven’t powered it up yet—I’ll do that tomorrow, probably. I also need to breadboard or wire up the buttons for the keyboard so I can test it. It might even make it into the enclosure if things go well for me. I still need to figure out how I want to deliver power to the final product since the case is going to be a little tight. Maybe just a JST pigtail for now. We shall see.
An astounding mash-up of simplicity and function. Crack on. This is brilliant.!
In case anyone’s interested, I’ve been experimenting more with CircuitPython’s sample playback abilities. I’d originally thought that when samples were loaded into the program they would get loaded from the filesystem into RAM, but that’s not the case. The sample is ‘streamed’ from the Flash memory directly (which, in CircuitPython, presents itself as a FAT-formatted USB drive to the host computer). Combined with the 16MB Flash on this board I’m using, that presents a lot of possibilities.
To test it I just had it play a 10.7MB, 2 minute long WAV file. It worked flawlessly. Very pleasing! I guess I should investigate using SD cards for a future build, and then never think about WavTrigger boards ever again…
Keep me posted. I still cant bear to pay for the WavTrigger.
As a youngster I used to get valves and bits from jumble sales. I wonder how long it will be before older mcu etc, will hit the charity shops.
Paper Man with the Red Steam from the Plumbutter.
Sorry, but what’s the deal with the paper circuit? I don’t think I’ve ever heard of this before, and I’m totally curious!
Paper Circuits are a fun way to prototype and flesh out ideas, or make circuits without the need for a circuit board 
Peter Blasser made them a fun DIY thing in the noise world, but he acknowledges that the idea of paper circuits have been around for a very long time -
for instance, an old 4MS pedal before they became well known they had another name and did up paper circuits as pedals - Tremelus Lune -
For instance this Atoner
Peters are noise based -
https://www.ciat-lonbarde.net/ciat-lonbarde/paper/index.html
https://www.ciat-lonbarde.net/ciat-lonbarde/rollz5/index.html
Rollz-5 are some of my favorites
I find this kind of thing (the maze of wires) strangely beautiful. What is decidedly NOT beautiful is the state of my desk after finishing the wiring and soldering for this thing. I think the final result is going to be pretty awesome. Happy with this result.
Finally got around to testing these things. Conclusion, they suck.
I tried out a bunch of different LDRs and LEDs. Here’s the best combo I could find, vs that same combo in a shrink tube DIY vactrol, vs a VTL5C3 from Thonk. The lens passes too much background light at low current, and loses too much light at high currents. I’ll be sticking to shrink tube.
Do you match your LED color to the peak sensitivity wavelength of the LDR?
Yes. I tested various colours. Without surprise, I got the best response from the green leds, closest to the LDRs peak sensitivity.
Yeah, I plan to get super bright, glass-clear, flat-top LEDs when I end up needing to make vactrols. I figure the flat ones are a little shorter than the domed lens ones, and they’ll sit flat against the LDR, making things more compact overall. I’ve got some plastic tubes that are a little more than 5mm (8mm, I think–they’re left over cores from rolls of doggie poop bags) but I haven’t decided if I want to use those or just do the heat shrink thing.
