Help needed to set up Audacity 2 for recording web radio

Audacity Help Forum GNU/Linux
1

Hi, recently I installed Audacity 2.0 in my openSUSE 12.1 system (PACKMAN repository version). As far as editing and playback is concerned it works as expected. Now I’m interested in recording web radio. I’ve tried several combinations (input/ouput sources, volume control and Software Playthrough option) and got various results ranging from horrible screeching noise to flat line being recorded to Audacity freezing… I can always record web radio using my laptop’s internal mic but the quality is bad. I noticed that in my Audio Information under Help at the end of the list I get the message “Unable to open Portmixer”. BTW, in the audio devices list I get the following devices

[pascal@pascaLinux:~/Music/Audacity Examples] $cat audio.info 
==============================
Default capture device number: 4
Default playback device number: 4
==============================
Device ID: 0
Device name: HDA Intel: STAC92xx Analog (hw:0,0)
Host name: ALSA
Input channels: 2
Output channels: 0
Low Input Latency: 0,011610
Low Output Latency: -1,000000
High Input Latency: 0,046440
High Output Latency: -1,000000
Supported Rates:
==============================
Device ID: 1
Device name: HDA Intel: HDMI 0 (hw:0,3)
Host name: ALSA
Input channels: 0
Output channels: 8
Low Input Latency: -1,000000
Low Output Latency: 0,011610
High Input Latency: -1,000000
High Output Latency: 0,046440
Supported Rates:
    32000
    44100
    48000
    88200
    96000
    192000
==============================
Device ID: 2
Device name: sysdefault
Host name: ALSA
Input channels: 128
Output channels: 0
Low Input Latency: 0,042653
Low Output Latency: -1,000000
High Input Latency: 0,046440
High Output Latency: -1,000000
Supported Rates:
==============================
Device ID: 3
Device name: hdmi
Host name: ALSA
Input channels: 0
Output channels: 8
Low Input Latency: -1,000000
Low Output Latency: 0,011610
High Input Latency: -1,000000
High Output Latency: 0,046440
Supported Rates:
    32000
    44100
    48000
    88200
    96000
    192000
==============================
Device ID: 4
Device name: default
Host name: ALSA
Input channels: 32
Output channels: 32
Low Input Latency: 0,011610
Low Output Latency: 0,011610
High Input Latency: 0,046440
High Output Latency: 0,046440
Supported Rates:
    8000
    9600
    11025
    12000
    15000
    16000
    22050
    24000
    32000
    44100
    48000
    88200
    96000
    192000
==============================
Selected capture device: 0 - HDA Intel: STAC92xx Analog (hw:0,0)
Selected playback device: 4 - default
Supported Rates:
    44100
    48000
    88200
    96000
    192000
Unable to open Portmixer
[pascal@pascaLinux:~/Music/Audacity Examples] $

My question is this : Is it possible to set up my laptop/Audacity to record directly, i.e. without using the mic, web radio that’s currently playing?

Many thanks in advance,

  • Pascal
2

That’s probably not a problem. I’ve often seen that on setups that work perfectly. I think it is just an information thing rather than an error (though I don’t know its significance if any).


As you don’t appear to have PulsseAudio running it will depend on your ALSA drivers.
Have a look in the recording (capture) settings in AlsaMixer and see if there is an option to select “Mix” (or similar) as the capture device.

To open AlsaMix, open a terminal window and enter:

alsamixer

To exit AlsaMixer, press the Esc key.

For the AlsaMixer manual, open a terminal window and enter:

man alsamixer

To quit the AlsaMixer manual, type the letter “Q”.

3

Just a quick addition:
Although installing PulseAudio should provide an option for recording sounds that are playing on the computer, you need to be a bit cautious about installing PulseAudio as it links deep into the system and can be very difficult to remove if you have problems with it.

Have a look at AlsaMixer first, if you have a “Mix” option then that will probably be the easiest solution. If you don’t then we can look at other options.

4

Thanks for taking the time to investigate my problem. As it turns out, I may have PulseAudio already installed

[pascal@pascaLinux:~/Music/Audacity Examples] $ps aux |grep pulseaudio
pascal    2490  2.1  1.2 246788 37784 ?        Sl   11:15  13:26 /usr/bin/pulseaudio --start --log-target=syslog
pascal   29637  0.0  0.0   3788   764 pts/1    S+   21:54   0:00 grep --color=auto pulseaudio
[pascal@pascaLinux:~/Music/Audacity Examples] $

It should be showing in the Device Toolbar, right?

Another thing. Today I managed to have my first line recording of web radio. Problem is the procedure is not consistently reproducible. In fact, it only happened once when I quit Audacity and the system informed me that there was still another instance of Audacity running. I had to manually kill that before I was able to start Audacity again. Something must be wrong with my audio setup.

  • Pascal
5

If PulseAudio is running when Audacity is launched then it should be listed in both the recording (Input) and playback (Output) boxes of the Device Toolbar and in the “Help > Audio Device Info”.

6

I followed the instructions in https://forum.audacityteam.org/t/playback-issue-with-pulseaudio/23013/1 and created a /etc/asound.conf file. After reboot PulseAudio appeared as pulse in both input and output devices. However, the volume control for input is greyed out (set to max). Still, I can record fine but the quality is bad (worse than that achieved by the internal mic) with cracks all over. Also, it appears to be slightly biased towards the negative sign.

Any ideas how to improve the quality or how to un-grey out the input volume control?

7

That is by design. The PortAudio audio interface Audacity uses can’t consistently control the pulse input level control due to technical limitations. If you select the (hw) direct hardware choice in Device Toolbar’s input device you might be able to control the input slider.


Have you installed pulse audio device chooser? You may actually be recording from a monitor of the internal mic or similar.

Have you tried adding this to the bottom of your /etc/asound.conf file?

    pcm.StereoMix {
    type pulse
    device alsa_output.pci-0000_00_1b.0.analog-stereo.monitor
    }

You have to get the device name (after “device” above) by running

pactl list | grep -i "monitor source"

in a terminal. If this works then you should have a “StereoMix” input you can choose in Device Toolbar.

These tips are Steve’s detective work so he will be able to help you later if you still have issues.



Gale

8

Wow! I can’t believe my ears and eyes! Stereomix now appears in my Devices Toolbar AND the recording is perfect! What’s more, no need to adjust the input volume control (it’s still greyed out) as it is a a true WYHIWYG process.

Thank you both Gale and Steve :smiley:

  • Pascal

PS. The device name was actually the same as yours.

9

Before that trick I was actually doing just that, i.e. record from the internal mic disguised as pulse. padevchooser is not available to openSUSE but I installed it now to Fedora. It’s not a widely known pulse audio utility, though it clarifies things a bit.

  • Pascal
10

padevchooser is not particularly important. The important thing is that installing padevchooser will also install PulseAudio Volume Control (pavucontrol).
The main benefit of padevchooser is that it gives convenient access to pavucontrol (but pavucontrol should also be available in the applications menu, or you could create your own launcher.

pavucontrol shows a lot about what is going on in PulseAudio and provides important controls. PulseAudio recommend installing pavucontrol if PulseAudio is used.
You may find this article of interest: http://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/PerfectSetup (though some of the information is now out of date).