MODEP with Raspberry Pi 1

[Tarrasque]

Hi all.

Is the old Raspberry Pi 1 / Raspberry Pi 0 powerful enough to support a MODEP / PiSound setup using as a guitar stompbox? How many plugins can I reasonably expect to chain before incurring in XRuns and other problems?

If not, what’s the minimum Raspberry Pi “generation” suggested to make an usable stompbox?

With “usable” I intend being able to at least chain a compressor, distortion, modulation, delay, reverb and amp simulation plugin in mono.

Thanks

[whofferbert]

Hey Tarrasque, welcome to the forums.

I have a Pi 0, but no pins soldered to it, nor any Audio HATs to attach and test this with. From the rest of my experiences with MODEP, I suspect it would fail to run properly. Possibly might not even boot.

I’d recommend getting at least a Pi 3 B or B+ to be on the safe side. I can run a pretty slick pedalboard on my Pi 3B+ with some comfortable headroom on the CPU and RAM, but i will always inevitably get a couple xruns with enough play time. The xruns never seem to present themselves as clicks or pops, as they sometimes do if they happen while I’m recording stuff.

There’s some info from the forums where MODEP was successfully running on a Pi 2, which at least has multiple cores:

MODEP not booting on RPi 2 and USB sound card issues [Solved]

Hey, since 2018-08-31, a real time kernel was added to the image, this is likely the cause for it failing on RPi2. Could you try running [Release] MODEP 2018-04-03 on RPi 2? This would be the last thing for you to try out, I’ll try to get a RPi 2 myself some way to be able to fix the issue of latest images. For USB sound cards you usually have to increase the buffer, try using -p 512 -n 3. If that does not help, please start a new topic

For running an OS and real time audio processing at the same time, you will want to have something with multiple cores. From the above, it seems the RPi 2 is not even handling the current real-time kernel well, even though it has 4 cores.

[Tarrasque]

I get it, that’s what I suspected.

I asked only because I have an old Pi1 floating around ad I wanted to test and play with MODEP before getting a new Pi4 when it’s supported.