[LAD] Pipewire help?

[John Murphy]

On Sat, 22 Jan 2022 13:57:45 -0800 (PST) Len Ovens wrote:

> I am not sure why PW, in it's JACK compatibility does not allow one of the 
> devices to be chosen as master and called system:* for compatibility with 
> all the JACK software out there... but it is what it is. I am sure someone 
> will come up with a configuring app(let) that does this better for 
> profesional audio use. To be honest, I am not really sure what optimal 
> would be.
> 
And yet, it seems that 'system:*' does exist in some form and plays a role.

I've been trying to do without QjackCtl Patchbay and I've deleted the
virtual-sink.conf I made, so Pipewire is back to defaults. I prefer to
not hear audio while testing, so I use a meterbridge.

$ pw-link -i
Midi-Bridge:Midi Through:(playback_0) Midi Through Port-0
Midi-Bridge:M-16DX:(playback_0) M-16DX MIDI 1
alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0
alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX1

but:
$ meterbridge -t vu -n myvu alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0
Registering as myvu
Can't find port 'alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0'

whereas:
$ meterbridge -t vu -n myvu system:playback_1
Registering as myvu
(and it creates a link)

$ pw-link -l
alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0
  |<- myvu:monitor_1
myvu:monitor_1
  |-> alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0

I can then play a file with:
$ jack-play -u a48k.wav
jack-play: a48k.wav

make the link and watch (and hear) it play:
$ pw-link -P jack-play:out_1 myvu:meter_1

$ pw-link -l
alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0
  |<- myvu:monitor_1
myvu:monitor_1
  |-> alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0
myvu:meter_1
  |<- jack-play:out_1
jack-play:out_1
  |-> myvu:meter_1

Great! But then, I can't get it to work without the meterbridge
and I wonder if I need a 'bridge' as well as a Pipewire link.

This is what happens without the meterbridge:

$ jack-play -u a48k.wav
jack-play: a48k.wav

$ pw-link -P jack-play:out_1 alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0

$ pw-link -l
alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0
  |<- jack-play:out_1
jack-play:out_1
  |-> alsa_output.usb-EDIROL_M-16DX-00.pro-output-0:playback_AUX0

I think that's the same without going via the meterbridge, but no sound.

If I take meterbridge's insistence on linking to 'system:playback_1' as a hint:

$ pw-link -P jack-play:out_1 system:playback_1
failed to link ports: No such file or directory

So; I can carry on using QjackCtl and its Patchbay, or work via a meterbridge,
or?

-- 
John. Needing help again.