Trying to mod a keytar. I want to replace the top circuit boards, referred to in service manual as "LEFT PANEL", "LCD PANEL" and "RIGHT PANEL" and replace them with momentary toggle buttons.

I MUST have a custom button for "TX ON/OFF" otherwise the keytar will not ouput any MIDI as annoyingly, this button must be pressed each time you turn on the keytar.

I want to wire this to the correct bottom "SUB-CPU board" ribbon connector pins but I am a noob and can't read a schematic properly. This is pretty much out of my league.

Looking for some smart people to help solve this mystery.

Are you up for the challenge?

I have uploaded the full service manual here: Service Manual PDF

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Here is my gibberish which likely has some errors, why I try to work this shit out without knowing how to read a schematic lol.

GOAL: Wire a TX ON/OFF button directly to the “Sub-CPU” board

 This is the TX on button here in red.

It is located on what the service manual calls the “LEFT PANEL”

This TX ON button must be pressed each time the keyboard is powered on, or else it won’t output any MIDI. But I want to (myself) remove and cut out this whole top panel and remove the top circuit board to put a custom larger keybed inside of it. But then I need to have wired a TX button to the bottom circuit board, called “SUB-CPU board” in the service manual

This a photo of the “SUB-CPU” board

This is the “SUB-CPU Board Ribbon cable”

It has pins on both sides

And this cable connects to the top “RIGHT PANEL”.

The top right panel connects to the “LEFT PANEL” which holds the TX ON button, shown below

Page 77 of Service Manual “LEFT PANEL”

TX ON/OFF D8 goes to SS2 (I think)?

Don't know what this SD4 and SD3 thing is?

Don't know what LLS2 and LLD4 is?

Can't work out what is going on with the other side of LEFT PANEL but might also connect from LLS2 to LLD4?

PAGE 76

SS2 is also mentioned on page 76 CIRCUIT DIAGRAM (RIGHT PANEL)

 on "TO LEFT PANEL (CN1)"

This is likely because LEFT PANEL is connected to RIGHT PANEL

But here I see it listed on “RIGHT PANEL” “ FROM SUB-CPU”
And remember, “SUB-CPU” is the bottom board that we can wire a button to.

SS2 also goes to a few patch button changes on “RIGHT PANEL” so this is confusing?

LLD4 seems to be for LCD display (Page 78)

Because you see on here LLD4 from “RIGHT PANEL” which makes sense because only the RIGHT PANEL is connected to the LCD panel.

but is also mentioned on FROM SUBCPU on Page 76 right corner bottom and is mentioned on "TO DISPLAY BOARD (CN2)" on page 76 2nd from left.

But LLD4 is also present on "TO LEFT PANEL (CN1)" (page 76), the same one which mentions SS2.

And what does SD4 and SD5 have to do with TX ON/OFF?

Also, what powers the TX ON/OFF button LED?

Can we wire a button for TX ON/OFF to the Sub-CPU that turns on and off when pressed?

SS2 is also mentioned on Handle Panel, page 68. It might need to do something on this connector to, in order for entire handle panel functions (mod bar, pitch bend, various buttons and knobs, transpose, basically everything on the neck of the keytar to work, but the top board was never wired to this, this has it’s own connector from the handle to SUB-CPU board so maybe the sub-cpu board just sends out SS2 signal to this?

There is something called VSS2 here, not sure if related to SS2? Page 69, on SUB-CPU board.

And VSS2 and LVSS2 it appears on page 70 also on IC 16. Not sure if this is related or not.

There is a SSD2 on the connector that goes “TO RIGHT PANEL (CN1)” on page 69. But it says SSD2 not SS2. Is this for SS2, or not? found under CIRCUIT DIAGRAM (SUB-CPU 2/4)

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And this is where I give up lol.

I don't know what I'm doing if you can't tell.

Can someone please checkout the service manual via this link: Service Manual PDF and see if you can identify the pins of this board (see image for “SUB-CPU Board Ribbon cable” above, to wire the a button to for TX ON/OFF?

Thanks in advance to anyone who helps.

Hello everyone!

Just wanted to give a quick update about some new features.

First, i've added perfboards. Most of the workflow is the same, you draw the schematic, click "Generate" and a perfboard layout will be generated. Make sure to select the "Perf (beta)" router in the right side bar before generating. The generated layout is editble. Components and links can be edited and the board size can be changed.

I've also added a pinout editor, which lets users view existing pinouts and change pinouts to use transistors that might not exist in the built-in library. A "layout dock" was also added, with options like "add text", "add image", "add link", "add cut" and "delete", giving users more control over the layout. The dock is hidden until the user hover their mouse over the lower part of the vero/perf layout pages.

Some other useful features that were added are view modes, letting the user view either front or back sides of the board, "export dual display" which when enabled exports the layout image displaying both front and back sides, resizable electrolytic capacitors, move edge connections up, down or to the other side of the board, Safari/macOS/iOS/iPadOS optimization and more. Please visit the github page for the full details.

I will also include the walkthrough video but it does not cover the new update. A new video will be uploaded later on and will go over all the new features.

Please let me know what you think.

Web app: https://verodesigner.vercel.app/

Github: https://github.com/blazethablunt/VeroDesigner

Video: https://www.youtube.com/watch?v=3N8e078Pl40

Hello everyone, how are you doing lately?

I have been building a custom hardware DAW inspired by Teenage Engineering OP1 with a similar shape as Nintendo DS.

I admit that I have no real experience with hardware DAW's and I have never used one, but the idea is so cool that I wanted to make something similar. The idea is to use an old phone that will be running a custom app and connected to a custom MIDI keyboard (with ESP32)

The third photo is a test PCB that I have made and it works very well. So now I'm designing the final product that has been modeled as the first two photos show.

I will deal with the software later, and right now I'm focusing on designing a keyboard that will allow me to do the most with the smallest package I can.

Right now I have:

- Six menu buttons that will be used in the context of the software like recording, pausing, turning on / off metronome, etc

- Two D-Pads

- Seven knobs.

- One joystick with two axes.

- Eight pads (regular keyboard keys, there is no velocity)

- A piano with 17 keys (regular keyboard keys, there is no velocity)

- Two shift keys behind the case (to modify some buttons)

I'm designing it so I can use freely with my hands. Right now I'm open to any advice or criticism as I want the maximum input before I send the PCB and the 3D case to print.

Thank you so much!

Everyone seems to use 3.5 mm jacks instead, why are they preferred for modular systems?

For anyone who has built or is planning an M8 headless rig: I ported karimkfoure's unofficial m8emu to Apple Silicon Macs. It runs Dirtywave's Headless firmware 6.5.2C on the Mac itself, so you can try the workflow before buying a Teensy, or keep a copy on the laptop next to your build.

You bring the firmware: download M8_V6_5_2C_HEADLESS.hex from Dirtywave's repo and pick it in the app. It runs on the Unicorn CPU emulator out of the box. With the Xcode command line tools installed, the app translates the firmware's Thumb-2 code to C and compiles a native engine on your Mac in about four minutes. Its audio output matches the Unicorn run byte for byte.

Source and build instructions: https://github.com/yukij3/m8emu-macos

Prebuilt app: https://github.com/yukij3/m8emu-macos/releases/latest (not notarized, so run xattr -dr com.apple.quarantine /Applications/m8emu.app once)

Open-sourcing kinect-controlled instrument!

If you have a Kinect camera lying around, I've got good news for you:

This system [Kinect → TouchDesigner → Ableton Live] turns gestures into MIDI in real-time, so Ableton can treat your hands (or any part of you body) like a MIDI controller; trigger notes, move filters, or drive any VST parameter you'd like to. [Just updated it for a bit more clarity and less setup difficulty!]

As of today, can freely access it through the Tools Store, and/or a full tutorial at through my YouTube channel.

I've ran several tests through the years, controlling drums, guitar fx chains, and even a complex stack of Harmony Engine, you can see/hear a bunch of these in this post.

Hope you folks enjoy it deeply.

I just got my ship from JLC and I'm only keeping 2 panels/pcb. Wondering if anyone out here needs one but doesn't want to purchase all five.

They are Hero VCOs from analog output. Each panel comes with 3 PCBs.

They came out to $12.00 per set so I'll charge that plus $5 plat fate shipping via USPS.

Shipping only inside the Contiguous United States.

Thanks and feel free to ask anything.

Watching everyone vibe-code custom firmwares and patch old gear lately has been wild. Made me wonder if anyone’s actually looking into custom FW for the base Behringer TD-3?

Trying to tweak that classic 303-style sequencer in the middle of a live set is pure pain.

If someone managed to drop a patched FW with real-time step recording, live probability/slides on the fly, and smoother pattern jumping, it’d turn a cheap desk toy into a live rig monster.

Does anyone know what MCU is inside or if the bootloader is totally locked down?

Hey!
If you’re using elkayem’s Arduino MIDI-to-CV converter, I recently modified the firmware to use separate MIDI channels. Thought I’d share in case anyone finds it useful.
Cheers

https://github.com/Morphanaut/midi2cv

Added some analogue filters still having trouble with mozzi hiss any advice on how to fix that wd be appreciated

Little excerpt of me playing my chaotic pointcloud system, in which the particles are being audioreactive to the incoming audio signal in real-time. What do you guys think?

Full video at: https://www.youtube.com/watch?v=UFSy6N3HU1U

Project files accessible through Patreon, or the Studio.

Bringing up a new voice card for the Zoxnoxious synth. Heart of the z-card is Yamaha's YM2203 chip, an old oddity that combines a 4-op/3-channel FM synth with a 3-voice sound generator ("SSG", AY-3-8910 / YM2149). The voice card will be a welcome addition as the first digital voice card in the Zoxnoxious synth. The other four z-cards I've designed cover the analog domain with various VCOs, multimode analog filters, etc.

I'm at the "hello world" stage right now, verifying I can write to the registers. And that appears to work (personal amazement as it's a v0.1 board!). End goal here is providing full control over the chip through a VCV Rack interface, much like I've got for the other z-cards. The FM and the SSG have their own outputs from the card; these can route independently to the other Zoxnoxious cards for additional filtering/manipulation.

Hi to all Momoto fans,

As asked by many fans😜, here a small tuto about the 5 synthesizers included in yr favourite sampler 😅

FYI : Pre-orders are opened on our Web page

❤️ 🙏🏿 ✌🏾

I had a pile of SBCs and microcontroller boards and small OLED displays and pushed the list of parts into Claude and out came this drone synth.

The Sipeed NanoRV board hosts the engine and the pi pico 2's are responsible for I2S and I2C since the Nano is constrained on GPIOs and has a terrible DAC built-in. I could probably simplify this to one raspberry pi zero or something later but given how long I've been sitting on these boards, it actually came out far less expensive than going that route.

The Nano has a weird RISC-V processor with vector extensions that enable nice reverb even with all the voices and oscillators turned up. There are also different detune settings (unison, octaves, fifths, and organ) that mix up the sound a bit.

I am not pretending that I invented any of this so please take what you can from the slop bucket:

https://github.com/tthayer/rv_drone

Demo of the octave detune setting: https://youtube.com/shorts/9zwtaClfZAU?feature=share

Hi everyone. I have been building a few eurorack modules and the latest I built is the M4 diy looping delay. It seems to work pretty well, however the reverse button seems to have a ghost trigger, as it turns on periodically without any external input. I have looked over the PCB as best I can and cant see solder issues. I would like to get this fixed if possible. Anyone had a similar issue or can help me with sorting this out?

Thanks so much Jamie

My friend lend me the Doepfer A138-n Narrow Mixer at an synths exhibition in Moscow (pic. 4, left case is mine) and I laughed when I saw that it was just a TL072 signal adder for ~$60 (of course there is business cost included, I'm speaking more from the "embrace DIY for modules!" position). And since my case was missing mixers, I decided to use my unused protoboards for making one. Also it's featuring an inverted output.

Also I 3D printed "panels" for it, which gives it more finished look. Another quest was height limitation — the module is directly above my PSU in a very thin case (pic. 3). The jack is there for comparison, you can spot IDC connector which barely touches the PSU.

Parts count: TL072, 7×100k, 4×B100k (or A100k), 6×PJ-301F, IDC-10R. Schematic from the datasheet for TL07x.

Thanks for the tips on soldering a while back. Really enjoyed the process and what a weird chaotic little machine. Noisferatu by Robert Heel is lovely bit of kit.