Raspberry Pi 4 (Page 1 of 2)

I see no reason that it wouldn't simply run as before, just faster.
except for a few things detailed here; https://www.tomshardware.com/reviews/ra...,6193.html
BTW, clock speed isn't up by much, prefetch is deeper, out of order execution, etc will help.
It will be interesting to see "bottom line" ptq improvements.

I have been resurrecting my pi project at a low priority - this could inspire me to raise the priority.

PS
No, you will need new version of the OS - maybe some libraries.
Now I'm starting to doubt this, some needed utilities may not be updated - yet.
Patience, I'll probably get one anyway - fixes will come, eventually.

The bigger ram might get me to try a software score display with page turning.

Now that's good news; last time I looked at Raspberry Pi's, it was still the model 2, with performances that were too modest for what I expected... I'll look at the stats of the new model, I may get convinced by it.

I have Pianoteq 6 stage trial up and running on a Pi4B.

The demo is playing as I type this :-)

The Pi4B seems to be generally available now - got mine from PiHut.

I have done similar to Edgar's guide but not put the tweak in for the Ethernet port, as I am not using it.

So:

-Installed Pianoteq 6
-Added the settings in limits.conf as per the README_LINUX.txt
-Installed cpufrequtils and used Edgar's script to launch, setting each core's governor state to performance.

I am presently using the PI4B onboard sound output.

I've played with Pianoteq for a few years but never been happy enough to use it professionally; it runs amazingly on my old but good-at-the-time PC, which is far too clunky to gig, and it just doesn't run well enough on my equally old but super cheap laptop.

I saw the claims for the PI4B and decided to give it a go for £55 for the 4GB version.

Back to my experiences.  I have the following settings in Pianoteq:

sample rate 44100Hz
audio buffer size 512 samples (11.6ms)
multicore rendering max
internal sample rate 22050

I am only however getting a performance index of 16, which doesn't seem greatly advanced on what some Pi3B+ owners with overclocking are reporting.  Certainly not the four times as fast as the PI4B has been made out to be.

But - with the sustain pedal clicked down (just for a laugh), and polyphony set to 48, it plays the demo without a pop or click.

The "audio load" shows about 30% in this situation, and resource monitor on the PI shows CPU use about 40% on the graph.

This suggests it's eminently usable for live stuff.

However...

If I drop the audio buffer size to 128 samples - about the upper limit of what I find playable, latency wise (2.9ms) - it pops and cracks even with the polyphony set as low as 8.

Maybe this is due to what is reported elsewhere, that the PI onboard audio is just not suitable for low-latency performance?  Anyone any thoughts on that? It certainly doesn't seem to be a CPU overload issue as the CPU use still doesn't get anywhere near max with the polyphony set so low.

I think I need to try a sound card or DAC hat.

Interesting, do you know if the audio jack of the RPi4 is still based on two PWM outputs or the new chip finally includes a decent audio codec? Otherwise, the usage of an external DAC connected to the I2S controller would be quite mandatory, like the previous models of this family of SBC.

Encouraged by your post scarlet_man, I ordered a Pi 4 2GB last week and got it set up yesterday. I’m getting surprisingly good results running Pianoteq Stage on it with an old USB DAC (Behringer UCA202), maxing out at these settings without getting audible glitches playing the demo:

Sample rate: 48000 Hz
Audio buffer size: 64 samples (1.3 ms)
Multicore rendering: MAX
Internal sample rate: 48000 Hz
Auto (Optimistic) polyphony limit looks to be around 24.

The only pre-configuration I did was:

sudo cpupower frequency-set -g performance

to set the performance governor state on all cores. PTQ shows a performance index of 17. Reading http://jackaudio.org/faq/linux_rt_config.html leads me to believe that the limits.conf changes are probably no longer required in Debian/Raspian.

Hearing the warnings about the Pi 4’s thermals and CPU throttling, I opted for Pimoroni’s fan shim. I think it’s worth considering. Testing PTQ without the fan, I can get the CPU close to thermal throttling temps after 30 mins or so playing. The fan keeps it to well below those temperatures. It might be that better passive cooling would be sufficient, but I'm not sure.

I’m really happy with these early results and like you I’m thinking a headless setup with LCD would be a fun project, and will certainly be a massive upgrade in sound for my lounge digital piano!

I'll be interested to hear how well the Pi DAC+ performs.

In my case, running Pianoteq without the desktop ( runlevel ≤ 3) obviously in headless mode, improved the performance (not acceptable anyway), but I could not see the index.
To configure Pianoteq I had to enter grafical mode (startx) and then reboot to play.

EDIT: this was on a Raspberry pi 3

I had a great deal of trouble finding a USB source that could put out 3 amps.
I looked mostly at USB-A chargers and they all seemed limited to 2.5 or less.
I know the DAC is going to take some current, although I know it will be a lot less than 2 x 20W.

Today I found this;
http://www.youdoitelectronics.com/manha...p;fep=7829

Slightly over $40 at the local store with tax, possibly cheaper on line, but I wanted it and I wanted it NOW !

So the PI-4 is up and running, I also had to get a HDMI to HDMI-micro adapter.
Everything else was a straight swap and plug from the PI-3, including the O/S that I had built a few weeks ago.
The original version didn't support Pi-4, so I had got the new one that is backward compatible to PI-3 and have been configuring and running it on the PI-3 while waiting for my PI-4

If I could give a suggestion...
perhaps, it would be worth to evaluate the chance to provide also an Aarch64 build of Pianoteq in addition to usual 32bit. Aarch64 provides more registers and typically it provides better bandwidth and performance, usually between 15% and 30%. Gentoo PI64 exists for RPi3 and I expect that it will exist also for RPi4 very soon.
Since 64bit versions already exists for other platforms, in my opinion, it won't be a bad idea to try.

Sincerely.

I'm curious about the latency one is seeing on pi4 using a DAC.  I found that the Dragonfly black 1.5 introduced a latency of around 25 ms on my Intel NUC i3 2.3 GHz system - unusable.  Does anyone have recommendations for a low-latency DAC for the pi4 or Linux x86?  I'm running Ubuntu with low-latency kernel.

Do you think that an USB DAC would be worse or you just didn't mention it?

Separate from this I have been testing the Pi 4 for use in a cluster.
This could be due to the efficiencies of a whole number of factors, (not least of which being the arm architecture and instruction set).
In building SAGEMATH from source a single Pi 4 is comparable to an I7 laptop (at 2.2 GHz., not the latest and greatest), i.e. around 6 hours wall clock time.

My plan is for a 4 node cluster, not for pianoteq but for general purpose computing.

Hello everybody,

The midifile's demo is working as I'm writing this lines !

It works perfectly on raspberry pi4.

Here are my specifications :

I made just the first advices from Edgar Bustamante (thanks to him !), without overclocking the cpu, without the ethernet configuration.

system : NOOBS ver 3-2-1
pianoteq version : 6.0.3 Standard (6.6.0 doesn't work for now because the launchfile doesn't appear as an executable... ?! maybe because of this I don't have all of my instruments the interface ? )
dac : HIFI DAC HAT from inno-maker (DAC PMC5122 up to 384Khz in 32 bits) available on Amazon...
you have to add this line in the config.txt (sudoedit /boot/config.txt) :
dtoverlay=allo-boss-dac-pcm512x-audio
no driver to install ; it seems to be directly recognize by NOOBS

Here are the Pianoteq configuration :

audio out : ALSA
out : BossDAC ; Direct sample mixing device
Channels : channel 1 & channel 2
frequency : 48000Hz (I have this choice only in the main menu but I can choose less in perf menu)
buffer : 96 samples (2.ms) the minimum I can reach
resolution : 32 bits (no editable)

Perf :
ident CPU : ARM, x4
fréq CPU : 1500 Mhz
perf indic : 22
multi-hearts on ; detect cpu overload : off
polyphonie tested with the sustain pedal on : 48

I can change the instrument during playback, I can navigate on Internet while listening, I can play very faster on the keyboard and no crack, no glitch... at over 64 polyphony on Grand Steinway model D, a cpu surcharge is detected (clusters, fast notes...) and the sound stops.

Now, I'm going to find how to use midi on raspberry...

I'll keep you informed !

Bye

Thank you so much for your message.

Indeed, I connect my "Prodipe Midi USB 1i/1o", and it  works perfectly when I select "Midi USB" in the options menu of Pianoteq 6.60.

For the last version, it also works ; I created the shotcut as the tutorial and it's ok. As we make the shell as an executable with the chmod, it works...

The latency is comfortable, I have to calibrate the velocity curve of my keyboard now.

Bye

After reading Edgar's howto I could not resist to buy a Pi 4 and start playing with it. After some changes I end up with a headless solution using the Pi 4 4GB together with the Suptronics new X400 v3.0 case. I installed the Raspbian starting from the Lite version and adding SSH and VNC interfaces using raspi-config and the GUI without login manager as explained here. The total installation including PQ6 occupy less than 2GB of my SD card.

Both SSH and VNC connections work like a charm from PC and mobile. Now I am trying to figure out the best strategy to run Pianoteq in order to make it usable but save resources at the same time. By reading various posts on this forum I am thinking about three possible scenarios:
1. Run vncserver at startup with PQ in fullscreen mode. I may connect with the mobile and have the nice configuration interface ready, at the cost of having some memory and CPU used by the GUI that is always running.
2. Use SSH to start/stop PQ in headless mode when I play and vncserver when I need to change the settings, usually only presets. I found ( but not yet tested) a nice app called Raspberry SSH Lite that can be configured with buttons to send commands via SSH.
3. Run PQ in headless mode only and change the presets by sending MIDI signals. I may also install some physical button to change few presets I use the most, and I understood that also the keyboard keys can be configured to send such signals.

Unfortunately I could not find instructions regarding the 3rd scenario, which MIDI signal to send and how. Someone may direct me to any document, post or else where to find such instructions?

Thanks for the hint Daniel, however I must admit my ignorance, what is written there it does not make much sense for me. I never used MIDI controllers until now so I'm running in the dark.

To start simple say that all I want to do is the possibility to change few of the existing presets. In the Option/MIDI panel I understand how to create a new action and assign the action of a specific preset, say Steinway B Jazz, and use Control Change or Program Change to trigger it. My problem is that I don't know what a Control Change or Program Change is and how to generate it via keyboard or command line.

If you know were I may find some howto or tutorial on this issue would be perfect

After playing for few weeks I finally got my RP4 box with Pianoteq running. I would like to share my experience in this howto. Any comment will be welcome.

When I started building my appliance I bought the 7" screen and assembled, but later I changed idea. There are several reasons that brought me to this conclusion:
- The screen is anyway larger and more delicate than the box. Using a mobile or a tablet connected via VNC is in my view more convenient and flexible.
- A headless box can be placed anywhere, even inside your piano (well, you don't need the box in that case) or away from it.
- The test I did suggest that this use require a fan for cooling. Playing piano even this small noise can be disturbing, but if you place the box on floor behind your piano can be acceptable.

I bought a Pimoroni Fanshim when I ordered my Pi4 but it turned out it doesn't work with the IQAudio hat I also bought to use as the DAC. I didn't want to wait for some passive cooling to turn up so I set the whole thing up 'just to try'

I have the Pi4 and the DAC attached to the 7" touchscreen, so the Pi is not in a case but open to the air but it sits at ~37c idling and gets up to ~50c when running Pianoteq Stage with me playing. That's cool enough that the PI4 isn't throttling at all that I can see. It would need to get hotter for that. It's meant I don't actually need a heatsink let alone a fan for the Pi4.

However, if you wanted to put it inside an enclosure or case it would get hotter. If you push the settings too far beyond the defaults then the Pi4 will have to work harder and you might need some cooling then but for my playing with the Stage version it works fine just open to the air.

[Edit: Some optimization after further research; systemd services ignore the limits.conf file, so it's crucial to enable the realtime scheduler in the unit file itself. Also, setting a fixed processor speed enables the "userspace" governor.]

I'm running a Raspi4 for some months now with a Hifiberry Amp2 and a SL 88 Grand. Absolutely satisfying setup. Pianoteq is running headlessly, internally with a sample rate of 29.4 kHz, host sample rate 44,1 kHz, 96 samples buffer size (2.2 ms). Set to a polyphony of 48.

I wrote a systemd service which starts/stops Pianoteq and sets up the CPU governor/frequency and volume level. Also I wrote udev rules which automatically start/stop Pianoteq if I switch on (connect)/switch off (disconnect) my master keyboard. This way Pianoteq is only running when I want to play.

The same Raspi is running Raspotify and the MPD Music Player Daemon. Pianoteq completely takes over the sound output when running, but as it gets stopped when the master keyboard is switched off, the other sound processes can just normally use the ALSA output.

pi@raspi4:~ $ cat bin/start-pianoteq
#!/bin/bash --

amixer sset 'Digital',0 190
sudo cpufreq-set -g performance
/home/pi/bin/pianoteq --headless --multicore max $@


pi@raspi4:~ $ cat bin/leise 
#!/bin/bash --

sudo cpufreq-set -g ondemand
amixer sset 'Digital',0 170


pi@raspi4:~ $ cat /etc/systemd/system/pianoteq.service 
[Unit]
Description=Pianoteq
Wants=multi-user.target

[Service]
User=pi
Group=pi
LimitMEMLOCK=500000
LimitRTPRIO=90
LimitNICE=-10
Nice=-10
Restart=always
RestartSec=10
#PermissionsStartOnly=true
ExecStart=/home/pi/bin/start-pianoteq
ExecStop=/home/pi/bin/leise


pi@raspi4:~ $ cat /etc/udev/rules.d/80-pianoteq.rules
ACTION=="add", SUBSYSTEM=="usb", ENV{ID_VENDOR_ID}=="9516", ENV{ID_MODEL_ID}=="2015", RUN+="/bin/systemctl start pianoteq"
ACTION=="remove", SUBSYSTEM=="sound", ENV{ID_VENDOR_ID}=="9516", ENV{ID_MODEL_ID}=="2015", RUN+="/bin/systemctl stop pianoteq"


pi@raspi4:~ $ cat bin/start-pianoteq-gui 
#!/bin/bash --

amixer sset 'Digital',0 190
sudo cpufreq-set -g performance
/home/pi/bin/pianoteq --multicore max $1

I'll set up a Github project if anyone is interested in collaborating to the scripts.
-- erik

I'm very happy with my installation now - everything works fine.
But one thing is not perfect: when I shut down the Pi (by a GPIO switch), the Pianoteq process is killed. So when I made some adjustments and didn't save them, they are gone when I restart.
My question: is there a way to quit the Pinateq GUI properly, but with a script when the system is shutting down?

Regards,
Martin

Hello all.

I'm running Pianoteq Stage v6.7.0 on a RPi 4 4GB with a ES9038Q2M I2S DAC. I fix the CPU frequency at 1500MHz and edited limits.conf according to README_LINUX.txt.

I start Pianoteq with the "--multicore max" option and audio settings are ALSA and Output "I-Sabre Q2M DAC [...] Direct hardware device without any conversions".

I use Internal Sample Rate and Host Sample Rate both 32000Hz, buffer size 256 and max polyphony 96.

This works great, no crackles, even with fast, dense chords in the lowest registers with continuous sustain pedal.

Except one problem: if I don't touch any key or pedal for about 8 seconds or more, then the output is silent for the first fraction of a second if I play a note again (attack of note not audible). Like something in the system goes to sleep and needs to wake up. Not sure what though. This does not change if I change the audio settings. Any ideas?

Regards,
David

Hello dear Pianoteq friends!

I plan to install Pianoteq6 on my Rasperry4 (1GB) and then use it like a Digital Piano without the monitor and keyboard.

How long does your Raspebrry take to boot until I can play?

Can I turn off the Rasperry without shutting it down or do I always have to shut it down? Is it possible to use the OperatingSystem in read-only-mode?

I've written a bash script which shuts down my Pi after two hours of idle time. Or when I press a switch connected to GPIO 3. It's not very elegant, because I've never written a bash script before, but it works. If you need it, I could share it...

Could you please tell us the details of this other piano project--the sample source, etc?