Hi Simon. It is possible to switch the output audio other than by using qpwgraph. For most users that is the most convenient to use. Since Sonic Pi doesn’t know your audio set up on a Raspberry Pi it automatically selects hdmi for the audio output route, as every Pi has that route. Some for example do not have built in audio jack output eg all Pi5
The hdmi selection is hard coded into Sonic Pi. however you can use a terminal and the terminal utility pw-link to alter the output selection. I developed for my own use some ruby code which will run in a Sonic Pi buffer which lets you easily alter whether you are using hdmi, usb or buetooth output. Slight caveat is that it will select the first usb or first bluetooth output that it detects but in most cases you will only have one connected anyway.
The routines are shown below. For initial use I suggest you just post them into a spare buffer once run they will remain available until Sonic Pi is rebooted. Then add the commands gohdmi, gousb and gobluez to select the output route (assuming you have the relevant hardware connected). You can also use getCurrentData to show the current connection or deleteSCout to disconnect all SuperCollider output connections.
It is also possible to include the code in the init.rb file in the .sonic-pi/config folder. If you want to automatically connect a certain output route when you start Sonic Pi you can do a slight bodge by adding
in_thread do
sleep 2
gousb #or which ever connection you want
end
at the end of the the functions. This makes sure that the internal hardcoded routine is selected BEFORE you try and change it, Otherwise you can end up with both usb and hdmi being connected.
Th code was always intended for experimentation and it could be developed further but you may find it useful.
#functions to aid connecting and disconnectiog SuperCollider under pipewire
define :getCurrentData do
#first input ports
inputs = `pw-link -iI`.lines
set :hdmiL,inputs.grep(/hdmi.*playback_FL$/).first.to_i
set :hdmiR,inputs.grep(/hdmi.*playback_FR$/).first.to_i
set :usbL,inputs.grep(/usb.*playback_FL$/).first.to_i
set :usbR,inputs.grep(/usb.*playback_FR$/).first.to_i
set :bluezL,inputs.grep(/bluez.*playback_FL$/).first.to_i
set :bluezR,inputs.grep(/bluez.*playback_FR$/).first.to_i
set :avJackL,inputs.grep(/audio.*playback_FL$/).first.to_i
set :avJackR,inputs.grep(/audio.*playback_FR$/).first.to_i
#now output ports
outputs = `pw-link -oI`.lines
scOutPorts=[]
16.times do |i|
scOutPorts[i] = outputs.grep(/SuperCollider:out_#{i+1}$/).first.to_i
end
set :scOutPorts,scOutPorts
#now get all current links ids
links = `pw-link -lI`.lines
#extract SuperCollider:out links
linkOutputs=links.grep(/-.*SuperCollider:out/)
#extract id of each of these links to scLinks
scLinks=[]
linkOutputs.length.times do |i|
scLinks[i]=linkOutputs[i].to_i
end
set :scLinks,scLinks
end
define :displayCurrentID do
#update current data
getCurrentData
#display current link id#
puts "Current data. Note: a 0 signifies no ID found"
puts "hdmi L and R",get(:hdmiL),get(:hdmiR)
puts "usb L and R",get(:usbL),get(:usbR)
puts "avJack L and R",get(:avJackL),get(:avJackR)
puts "bluez L and R",get(:bluezL),get(:bluezR)
puts "sc output ports (16 max)",get(:scOutPorts)
puts "current SuperCollider output link Ids2",get(:scLinks)
end
#display the data
displayCurrentID
###################################################
#function to connect or disconnect SuperCollider
define :connectStereo do |output,input,type=1|
#puts "data",output,input,type
portlist=get(:scOutPorts)
case output
when :usb
if get(:usbL) == ""
puts "not available"
return
end
o1=get(:usbL);o2=get(:usbR)
when :hdmi
if get(:hdmiL) == ""
puts "not available"
return
end
o1=get(:hdmiL);o2=get(:hdmiR)
when :avjack
if get(:avJackL) == ""
puts "not available"
return
end
o1=get(:avJackL);o2=get(:avJackR)
when :bluez
if get(:bluezL) == ""
puts "not available"
return
end
o1=get(:bluezL);o2=get(:bluezR)
#puts "bluez",o1,o2
else
puts "not available"
return
end
if input == ""
puts "input not available"
return
end
if portlist[input-1] == "9" or portlist[input] == "0"
puts "outputs not available"
return
end
i1=portlist[input-1];i2=portlist[input]
action=["pw-link -d ","pw-link -L "]
cmd = action[type]+i1.to_s+" "+o1.to_s
puts cmd
system(cmd)
cmd = action[type]+i2.to_s+" "+o2.to_s
puts cmd
system(cmd)
end
#function to delete all SuperCollider output connections
define :deleteSCout do
getCurrentData
links=get(:scLinks)
return if links.length==0
links.each do |n|
cmd= "pw-link -d #{n}"
puts cmd
system(cmd)
end
end
###########################################################
#four functions that let you easily swap the main Sonic Pi output audio routing
define :gohdmi do
getCurrentData #they may have changed
deleteSCout
connectStereo :hdmi,1,1
end
define :gousb do
getCurrentData#they may have changed
deleteSCout
connectStereo :usb,1,1
end
define :gobluez do
getCurrentData#they may have changed
deleteSCout
connectStereo :bluez, 1,1
end
define :goavjack do
getCurrentData#they may have changed
deleteSCout
connectStereo :avjack, 1,1
end
#PLACE BELOW WHERE YOU WANT SONIC PI TO CONNECT WHEN YOU RUN THE CODE
#IF YOU HAVE MORE THAN ONE USB OR BLUETOOTH IT WILL CONNECT THE FIRST ONE IT FINDS
# choose from gohdmi, gousb, goavjack or gobluez (no audiojack on Pi5 or Pi400)
gohdmi
If you use this last command in init.tb then put it in a thread with a 2 beat delay as discussed above.
Any advice ?
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