JAAA Spectrum Analyser and the RPi - can't get it working

[rjmusto]

HI all,

In the past I have made good use of the JAAA audio spectrum analyser running on a RPi.  Neat and handy piece of software.

Recently thiough I have tried to get it working on a RPi 4 but all efforts have failed. The app runs ok, but no trace shows up - so not connecting to any inputs.
This is no doubt something to do with how the Pi is handling the audio - have tried removing Pulseaudio, which can get in the way, but so far nothing I've tried has got it working.

Anybody on here had success with this? Any tips on what is needed?

Thanks,
Ralph

[mag_therm]

I was also unable to get jaaa to work stand -alone. (Fedora 32)
Do you have jackctl installed?

Firstly I open amixer or alsamixer to set the audio capture  at 0dB at hw level.

Then start jackctl with >setup connecting to the sound card I want.
In > setup > options there are cmds you can add to momentarily kill pulseaudio, then restart it.
I can give you those if needed.
That allows pulseaudio to work with jack, but I am not understanding fully how.

Then open the graphic (GUI)  patchpanel ( it is miss-called "Graph" lower left button).  A lot easier to use than the >PatchBay

Then invoke jaaa. It will immediately show on the GUI.
You can pull  the green cables to connect to its In_1 and In_2 The jaaa outputs do not work here.
The jaaa should start to display.
Re-Set the analog alignment level in alsamixer  to match jaaa dBfs level according to your noise floor.
I set it about -20dBfs  for  0dBu 0.775 Vrms  but there are various other standards.
Set jaaa low dBfs , 16 bit noise floor is about -80 to -90 dB approx .
Setting freq on jaaa seems to need the full string like this:  3.0k for 3000 Hz range ( need to enter the decimal point and k

You can also start calf  now, and patch in its filters etc
Hope this helps.

[rjmusto]

Hi,
Thanks for the detailed reply.

I haven't used Jack previously, so on a bit of a learning curve here...

I have it installed and got as far as your
"You can pull  the green cables to connect to its In_1 and In_2 The jaaa outputs do not work here."
part, but am at a bit of a loss what the green cables are here. Have I missed a step in the process perhaps?

The screenshot shows what I am looking at.

Many tahnks.

[mag_therm]

From your png, I can see that you do not have a capture enabled.
>Setup
In settings, > "Interface" will drop down to show the available ones.
Use alsamixer or amixer to help if you have a lot of them.
I use Driver: alsa  Rate 48000 frames 1024 periods 2

>Options # add the cmds
 "Check  Exe script on startup" :   pulseaudio -k
 "Check  Exe script after startup": pacmd load-module module-jack-source channels=2; pacmd load-module module-jack-sink channels=2;

Everything else at defaults
Now save that setup in settings "My_pch_capture",  you can make one file for each capture sound card

#It was difficult for me to realize that the whole jackctl seems to be able to only run on the one capture interface.
#It is not able to handle more than one stereo channeI have not tried 2 instances of jackctl yet.

"My_pch_capture" is exe when you select it and >apply >OK
When that is successful, the capture interface will appear on left side of the GUI, so you can pull cables from it to jaaa.

To pull a cable.
left click on a green  output terminal -it will turn blue.
Hold left click then pull the blue cable, it will snake after your mouse as you pull it to the input terminal.
If all is good, the blue cable will turn green.
As I mention jaaa outputs do not work, so pull more cables from input to system playback

[HB9EVI]

you don't need jack to run jaaa or japa; just start them with the -A flag and it uses the regular alsa devices.

if you're not going to run your own home studio, it's not worth the pain run jack; it's a rather complexe piece of software in every days life not really necessary; I run jack only on my home studio workstation, everywhere else I just use alsa/pulseaudio

[rjmusto]

Ok, was being a bit of a numpty.....I didn't have the USB audio dongle plugged in, so the correct interface never showed up.

Now it's working. Happy days.

HB9EVI  :-

I never got it to work with -A. No idea why, but ah well, I've learnt a bit about Jack......

73
Ralph

[mag_therm]

One of Jack's problem is the lack of documentation.
I am feeding ft8 mode  to wsjt-x. I wanted to go through some af filters for ssb too so calf is useful. jaaa is a better s.a. than the one in calf
 It took me a long time to figure out alsa and jack . I have written some down but still don't have a good understanding of it.

Here is Fedora 32:
[PR_mag_therm@localhost ~]$ man jaaa
No manual entry for jaaa
[PR_mag_therm@localhost ~]$ man jack
No manual entry for jack
[PR_mag_therm@localhost ~]$ jaaa --help

Jaaa-0.8.4

  (C) 2004-2010 Fons Adriaensen  <fons@kokkinizita.net>

Options:
  -h                 Display this text
  -name <name>       Jack and X11 name
  -J                 Use JACK, with options:
    -s <server>        Select Jack server
  -A                 Use ALSA, with options:
    -d <device>        Alsa device [hw:0]
    -C <device>        Capture device
    -P <device>        Playback device
    -r <rate>          Sample frequency [48000]
    -p <period>        Period size [1024]
    -n <nfrags>        Number of fragments [2]

  Either -J or -A is required.

[PR_mag_therm@localhost ~]$ jaaa -A -d hw:1
Can't connect to ALSA
[PR_mag_therm@localhost ~]$