I already have a sound card


I already own a stereo i / o audio device , a Steinberg UR22 , with usb 2.0 , can i control it with Zynthian?

It works with jackd on my computer

i’m searching for a synth and plugin host that receives midi messages from my korg esx and do its module, and also an effect rack that processes incoming analog audio input and send it to analog output, without digital distortion.


Hi i forgot a couple of questions.
Can i avoid to buy the integrated sound card and use this one?
I need to play in real-time without xruns, , any informations about stress tests and how much the cpu could carry without troubles would be appreciated, especially for the sounds of zynaddsubfx that have strong delays and attacks. Thank you and good bye.


Hi @tony-j,

I think there are not many zyhtians around using a USB-Interface - at least that is my observation.
My guess is that having a small one-box-device is the way to go for most because the whole GUI is made for being controlled by a certain case design centred around a special display and knobs layout.
You can find examples here:

Besides additional driver issues with a lot of sound cards USB seems to add to latency…

About your second question: For the most part it woks fine on the Pi3 but zynaddsunbfx is totally able to cause xruns if a very complex patch is beeing used especially in combination with high polyphony. The synth is sadly just using a single core of the Pi`s 4 cores.



Hi @tony-j

So you should not use a USB audio card. It adds latency. No way to get around this. But I think you should try if additional latency is a problem for you. Zynthian itself is (currently) not created for this usage, so perhaps you have to do some optimizations by your own.

You can only avoid xruns by careful selecting your plugins. There are some plugins which may produce xruns faster than others - also depending on the selected sound of the plugin (as @lod wrote).

This is a common problem of sound synthesis. There is not much place for multithreading plugins. At the end you have to wait for the next calculation for the buffer from the previous calculation so multithreading often makes no sense.

I am currently trying to get the most of a Pi with CPU isolation: one core for jackd, one for engine(-stack). The rest for the system.

Compared with commercial synths: We can try to use every synth engine that’s “flying” around (which may overload the system (CPU/ memory)). Commercial synths won’t integrate a xrun-generating engine or will use a better hardware… so we are the sound designers and users and have to try by ourself what is working and what we should avoid.

Regards, Holger