Minimum HW for Midi over USB keyboard expansion

Hi guys,

You have no idea how I was excited to see you guys pulled it off!!!

I was looking for this solution for a LONG time… I tried to use an iPad with some apps on it, looked for a sound module or even considered replacing my entire keyboard to a new one just to add sounds…

Here is some background…
I own a Yamaha P-121. All I’m looking for is an extension for sounds/effects for the keyboard (mainly live performance, layering two sounds is more than enough). It is important the sound from Pi to be routed back to the keyboard and use the keyboards’ speaker for the new sound (minimum latency is a must obviously).

Basically, I’d like to download SF2 sounds, and pick the right sound using the AMAZING Zynthian!

My keyboard supports Midi over USB, so I’m not sure if I need the extension card or not…

I’m really excited to get started, but I saw there is a shortage of kits so I need to order some HW separately.

Can you guys advice if this list will do?

Pi4 – will 4GB memory be enough?

SD card – will 32GB be enough?

Screen – either Zynscreen1.5 or any HDMI screen I guess.

Controller set - can it be connected to the Pi4 or do i need the special Zyncsreen1.5?

Many thanks!!


Hi @Asaf!

Welcome to a new world of fun and lost hours…

Pi4 with any amount of RAM is fine.

SD card at least 16GB.

Screen can be HDMI.

Controllers are desirable but not necessary. You can drive it with mouse/keyboard. There are methods to connect rotary encoders directly to the Pi header. Check out previous posts and the wiki.

1 Like

amazing! thanks!

don’t forget a sound card.

mmmm… I thought sound will come from Pi to the keyboard through the midi-USB. Do I really need the sound card?

I think this feature is unique to this specific keyboard:
“Connecting the [USB TO HOST] terminal of this
instrument and the computer via a USB cable allows
you to transmit/receive MIDI and Audio data (USB
audio interface) to/from the computer.”

No, sorry! Zynthian supports OTG/gadget mode only for MIDI and using it in this configuration has challenges for powering the device.

Wow… Does this mean, the only way to get the sound out is either through the audio connectors?
If yes, I’m kind of stuck as this keyboard doesn’t have a sound in port…
Any workaround for the issue you described?

Zynthian is an audio generator / processor. It’s main purpose is to send audio to its outputs. It can be made to transport the audio over network though this isn’t supported out of the box. It is not designed to be an audio interface to other devices. I am interested to know whether your keyboard supports USB audio. If it does then you could add a USB soundcard to the keyboard and connect Zynthian’s output to it.

Ah! I’ve just read the user manual for the P121. It looks like it can connect as a USB soundcard so yes, this could work. You would need to configure Zynthian to use USB audio for its sound interface and the P121 would have to be powered and connected when the Zynthian starts up.

[Edit] This assumes the P121 appears as a class compliant USB interface or appropriate drivers are installed. The manual mentions, “Yamaha Steinberg
USB Driver” which might mean drivers are required which may not be available for Zynthian. There is support for UR22 so maybe it will work. Just try it! If you have a Pi and uSD then it won’t cost you anything.

Brilliant! The pi4 is on the way… promise to update how it goes!
Another HW Q… instead of wiring the knobs, any recommendation for a tiny USB controller which I can use to control Zynthian?
I found this one in Amazon, but it is maybe too small:

Better maybe will be any tiny USB MIDI controller. You can setup it sending midi note for control of Zynthian, see on Zynthian UI Users Guide - ZynthianWiki
Or use tablet and OSC Accessing Zynthian from your computer - ZynthianWiki

Thanks - I like the idea of the midi control. Do you happen to know any midi controller which is in the size of this guy (but not in that price :slight_smile: )

Better price has Behringer | Product | X-TOUCH MINI
But I have not direct experients with it.


I just got the Zynthian today, built it and started playing :slight_smile:
Tried to change the Soundcard to “Generic USB Device”, but since then the Zynthian is stuck on the “Zynthian” welcome page. The Web I/F is working, so once i change it back to “kit4”, all is back to normal.

It’s working!! just needed to configure the driver… THANKS!


People traditionally say thanks with a sound sample…It’s explained here . . .
Talk:Zynthian Wiki Home - ZynthianWiki

Nice :). Honestly, I’ve never done a sounds sample before (I pretty much play live and trying to use Zynthian as a keyboard expander for SF2 sounds on stage). I’ll do my best and see what happens - I’m not done yet with my small projects (need to control Zynthian from the keyboard and create some gui to switch sounds in one click only)… I’ll upload the projects once i’m done so people can use it if they choose to. Still reading a lot here :slight_smile:

Don’t worry it’s not obligatory in any way. I’ve submitted far too many bell recordings for reasons people have never fully understood, and even if it’s just a note from your favourite or least favourite patch it’s all appreciated.
Course submitting code get you in the VIP section . . .

…they still wont let me in.