OK, I’m pretty new to Zynthian (it’s my first project using it, so I’m not sure if I even put it in good category), but not complete novice in DIY electronics and synthesis, since I already made few simple projects like this.
So my new idea was to use open source Hammond Novachord emulation I’ve found and install it somehow on RaspberryPi Zero 2W I just ordered, together with touch sensitive LCD panel I bought, and to separate audio signal from the HDMI interface using cheap-but-reliable HDMI Audio Return Channel Adapter bought from AliExpress. I may make some wooden enclosure (with laser cutter) for everything later, too. Ofc I have MIDI keyboard to control the whole Zynthian engine, too.
I want to know if such approach makes ANY sense, or should I try different way to implement this exact emulation on RPi? Is Zero 2W enough? Does signal path like “RPi –> Audio Channel HDMI separator –> Audio Out & LCD panel” make sense? Pics rel
Welcome to zynthianland!! I’m pretty sure you will find lot of fun with us
This is a hard path and probably you will be almost alone in the dark. I would recommend a “standard” Pi4 or Pi5. Using HDMI audio output is not a good idea neither. We never got good results with this. I would recommend a decent I2S audio interface, specially if you want to perform and get good sound quality with low latency and little jitter. Indeed, if you want the lowest jitter, you should take care of using an audio interface with good clock generators.
BTW, i will test the “Hammond Novachord LV2 Plugin” ASAP and would consider to include it in the zynthian collection.
Honestly, I’m kinda too poor to afford proper (and overpriced at this point) Pi 4 or 5…
Maybe there’s way to do it bare-metal? I’ve heard bare metal approaches are really hard with most RPis.
Btw, I’m glad I’ve got reply from one of project leaders themselves! And good to hear you’ll consider adding Novachord plugin to Zynthian’s collection, too.
You don’t need an all singing and dancing pi. I have a pi4 1GB and it’s fine. You’d almost be better with a pi zero than any other board because other SBC’s invariably need unique kernels, or drivers which won’t be in the zynthian image.
PiZero2 is an arm64 device, so it’s not far from pi3 or Pi4. Most sure is not going to work out-the-box, but It could work with some adjustments.
Probably enough power to run smoothly a single not-too-weight lv2 plugin. It could run the zynthian ui too. It would use about 20-30% of one core., and pi0-2 has 4. Good enough.
I wouldn’t recommend running zynthian on a PiZero2. It may be possible and there may be some users for whom this would be benefical, but you will have issues under some (many) conditions. If you only want to run a single plugin then you would be better to write a script to start the relevant applications, e.g. a LV2 host running the plugin and input/output routing.
You can find new, and decently priced RPIs 4 and 5 on ebay, often from professional sellers. Plus if you put things on your watchlist you often get an offer from the seller.
Yeah, I already know it. Still, gonna use whatever I’ve already got, so will probably compile that LV2 plugin specifically for PiZero2 – not bare metal way, since I already installed lightweight Raspbian version on it succesfully.
So, FIRST UPDATE:
I managed to install Raspbian OS on Pi Zero 2W, which hypothetically should be easier than it actually was – mostly because microSD card I used as Pi’s storage was either too large for RPi to handle, or it was simply corrupt. After switching to smaller, more reliable card, it went quite smoothly (for that hardware’s standards, it was quite slow and laggy, but mostly functional).
