Virtual Sound Card?


km4ack
 

I want to use two different applications to monitor the same frequency at once with one USB sound card. I understand this can be done with "virtual sound cards" but have no idea where to start. Can anyone point me in the right direction?

73, de KM4ACK
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Unfortunately the wiki write up is missing at https://nw-digital-radio.groups.io/g/udrc/wiki/home
but it is based on the information here https://github.com/nwdigitalradio/split-channels
Read up on pulseaudio and create multiple instances in asound.conf



On Fri, Nov 1, 2019 at 3:37 PM km4ack <jason.oleham@...> wrote:
I want to use two different applications to monitor the same frequency at once with one USB sound card. I understand this can be done with "virtual sound cards" but have no idea where to start. Can anyone point me in the right direction?

73, de KM4ACK
Find Me On Youtube



--
John D. Hays
Kingston, WA
K7VE

 


km4ack
 

Thanks John!

73, de KM4ACK
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David Rhoads
 

Hey Jason,

I don't know if you have heard of Jack. I have been fiddling with it a little lately for audio production work. It somehow acts as an interface between pulse audio and the applications. Then there's an application called jackctl I believe that lets you select which applications to send the audio to. I'm not sure if this would work for ham radio, but it's probably worth a shot.

On Fri, Nov 1, 2019 at 3:37 pm, km4ack <jason.oleham@...> wrote:
I want to use two different applications to monitor the same frequency at once with one USB sound card. I understand this can be done with "virtual sound cards" but have no idea where to start. Can anyone point me in the right direction?

73, de KM4ACK
Find Me On Youtube


Siegfried Jackstien
 

no need to use virtual sc ... just select in both app the same input device

dg9bfc sigi

Am 01.11.2019 um 22:37 schrieb km4ack:

I want to use two different applications to monitor the same frequency at once with one USB sound card. I understand this can be done with "virtual sound cards" but have no idea where to start. Can anyone point me in the right direction?

73, de KM4ACK
Find Me On Youtube


Ray Wells
 

I've had a great lack of success getting Jack/qjackctl to play with USB sound devices. The short version is it doesn't "see" the likes of CM108 and Behringer UCA202 USB sound devices. I understand the alsa loopback option is a way around this but I'm too old and grumpy to be creating convoluted sound configuration files (;->)

To shoot you in a different direction, Linux kernel AX25 has been able to use multiple programs with a single TNC/sound card since day one. Just give each program a different SSID and point them all at the same portname that's listed in axports. Or, If you're using Direwolf check out its AGW port option for multiple programs. This from the Direwolf User manual ...

4.3 AGW TCPIP socket interface
Dire Wolf provides a server function with the “AGW TCPIP Socket Interface” on default port 8000. Up to 3 different client applications can connect at the same time.

HTH
Ray vk2tv


On 2/11/19 10:20 am, David Rhoads wrote:
Hey Jason,

I don't know if you have heard of Jack. I have been fiddling with it a little lately for audio production work. It somehow acts as an interface between pulse audio and the applications. Then there's an application called jackctl I believe that lets you select which applications to send the audio to. I'm not sure if this would work for ham radio, but it's probably worth a shot.

On Fri, Nov 1, 2019 at 3:37 pm, km4ack <jason.oleham@...> wrote:
I want to use two different applications to monitor the same frequency at once with one USB sound card. I understand this can be done with "virtual sound cards" but have no idea where to start. Can anyone point me in the right direction?

73, de KM4ACK
Find Me On Youtube


Mark Griffith
 

Yeah, you can use a SignaLink USB to receive audio from two radios using the plain old audio jacks in the back.  No need for a custom cable  Then use two apps to read the audio input from the alsa 1.0 port.

Unless you don't have a SignaLink.

Mark
KD0QYN


On Friday, November 1, 2019, 6:52:26 PM CDT, Ray Wells <vk2tv@...> wrote:


I've had a great lack of success getting Jack/qjackctl to play with USB sound devices. The short version is it doesn't "see" the likes of CM108 and Behringer UCA202 USB sound devices. I understand the alsa loopback option is a way around this but I'm too old and grumpy to be creating convoluted sound configuration files (;->)

To shoot you in a different direction, Linux kernel AX25 has been able to use multiple programs with a single TNC/sound card since day one. Just give each program a different SSID and point them all at the same portname that's listed in axports. Or, If you're using Direwolf check out its AGW port option for multiple programs. This from the Direwolf User manual ...

4.3 AGW TCPIP socket interface
Dire Wolf provides a server function with the “AGW TCPIP Socket Interface” on default port 8000. Up to 3 different client applications can connect at the same time.

HTH
Ray vk2tv


On 2/11/19 10:20 am, David Rhoads wrote:
Hey Jason,

I don't know if you have heard of Jack. I have been fiddling with it a little lately for audio production work. It somehow acts as an interface between pulse audio and the applications. Then there's an application called jackctl I believe that lets you select which applications to send the audio to. I'm not sure if this would work for ham radio, but it's probably worth a shot.

On Fri, Nov 1, 2019 at 3:37 pm, km4ack <jason.oleham@...> wrote:
I want to use two different applications to monitor the same frequency at once with one USB sound card. I understand this can be done with "virtual sound cards" but have no idea where to start. Can anyone point me in the right direction?

73, de KM4ACK
Find Me On Youtube


yindra
 

I've used ALSA to split audio from the SignaLink into two applications.
Here is my .asoundrc

# playback PCM device 
pcm.amix {
  type dmix
  ipc_key 1234
  slave.pcm "hw:Loopback,0,0"
}
# capture PCM device
pcm.asnoop {
  type dsnoop
  ipc_key 1235
  slave.pcm "hw:Loopback,0,1"
}
# duplex devcie combinding asnoop and amix
pcm.aduplex {
  type asym
  playback.pcm "amix"
  capture.pcm "asnoop"
  hint {
    show on
    description "combines loopback asnoop(input) and amix(output)"
  }
}
pcm.!default {
  type plug
  slave.pcm "aduplex"
}
 
I would like to learn more about implementing Jack.


Terry L. Morris
 

Jason,
Try jack audio connection kit. https://jackaudio.org/

You might do some reading on the jack-alsa bridging kit at http://www.penguinproducer.com/Blog/2011/09/bridging-the-gap-using-jack-with-non-jack-apps/

I can't tell you specifically how to set this up but you asked for some clues. Enjoy your videos. 73 KB8AMZ


David Rhoads
 

Another possibility is Pipewire, which seems like a newer implementation of pulseaudio combined with some of the features of jack.


Not sure if this works on the Pi though...

73,
DE KD2FLZ

On Sat, Nov 2, 2019 at 7:39 pm, Terry L. Morris <hooked2u@...> wrote:
Jason,
Try jack audio connection kit. https://jackaudio.org/

You might do some reading on the jack-alsa bridging kit at http://www.penguinproducer.com/Blog/2011/09/bridging-the-gap-using-jack-with-non-jack-apps/

I can't tell you specifically how to set this up but you asked for some clues. Enjoy your videos. 73 KB8AMZ


km4ack
 

Thanks to all for the suggestions! Looks like I have some studying to do.

73, de KM4ACK
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