Zynthian raport

As promised in Exercises in absurdity, or ... M-Audio Code controller, starting what’s probably going to be an on-going raport about my Zynthian journey. In short, Zynthian is an open source, open hardware Raspberry Pi -based multiengine, multi-timbral synth/sampler with benefits. Such as also being a MIDI processor and an USB host, which should make it a nice pair with Pyramid. Some assembly is required, but if you can handle tiny screws and follow simple instructions, this is not hard at all.

The box arrived on Thursday, less than a week from ordering. Assembling the official V3 kit took something like two hours total, including interruptions to take plenty of photos, preparing and participating on family dinner. And then another two hours to go out to buy a microSD card for it (the kit doesn’t come with one and I’d kinda missed or dismissed that with “oh I have SD cards in the house”), prepare it with the image (not hard, but downloading and then writing down 10+ gigabytes of stuff on the card takes some time). And then chase around the house for a suitable USB power supply: another “oh I have those in the house” item, but those things truly are not all made equal: even if the supply itself says a thing, the cable might not deliver: Pi 3 will boot and run on with very little power but it’ll limp along in a survival mode, which made me think this is so not going to handle audio processing … before realizing that tiny red lightning symbol is an under-voltage warning, not a “running on AC power” symbol as it is on many devices. :smile: Once properly powered it feels quite snappy. So it took me an evening to get it up and running but most of that was just me not being prepared (and also not wanting to rush it).

With all that aside, it seems remarkably polished for this kind of a project that’s also being very actively developed. From what I briefly tried with the synth/sampler stuff, it “just works” and indeed seems like a nice pair with the Pyramid - in my case I’d been looking for a sampler and an USB MIDI host, and this comes with both. On top of multitude of synth engines and audio effects that is.

As mentioned in the M-audio thread, I only have a laptop in my studio for mixdown/master recording, and getting rid of it entirely has been a long-term plan. Zynthian can record and play audio, and these can be routed through an effect stack (arbitrarily large collection of LV2 plugins etc available) so it should work for that too. Tried this out yesterday and wasted good many hours on it, partly due to missing documentation and partly due to my own newbie mistakes / not really thinking it through: there actually two audio inputs on the box - one 6.3mm TRS jack for balanced mono input, and a 3.5mm TRS jack for unbalanced stereo input. The 3.5mm jack seems to be entirely undocumented - the Zynthian docs don’t seem to mention it at all, and even the card manufacturer docs just say “analogue input, 3.5mm phone jack” and nothing more. This combined with not really internalizing what I’d read on the build guide about the larger input jack which you do connect by yourself, coming from a software background I first suspected software bugs and chased a lot of ghosts before really realizing the 6.3mm TRS jack is wired as balanced mono. Says so right there in the building guide. Getting from there to having it actually accept and record input on the 3.5mm jack was a bit of a journey, probably largely self-inflicted due to messing with input selectors in the Zynthian mixer before recognizing them for what they really are. Still, the part about stereo input seems undocumented. Might have to do with this not being the most common of tasks for the box. Might also have to do with just me being a little too tired for the task. Tired as in “wondering for several minutes why there’s no sound coming out of anything when the mixing console is not turned on” -tired. :joy:

Anyway, it does indeed record stereo audio in a manner that seems perfectly sufficient for my purposes, so my studio is now entirely laptop free! :partying_face: That is, at least preliminarily so. Time will tell.

Next stop on the road is probably to mess around with the MIDI router, that I haven’t touched at all yet. Other than noting that yes it does see all the junk attached to an USB hub like it should: it is a proper computer inside, so there are no arbitrary limitations on how many ports you can have on a hub etc. From what I looked, the typical USB MIDI host standalone box either doesn’t support USB hubs, or is limited (eg Kenton says to support four ports on a hub).