Record external audio with Librem15rev2


#1

Hi,

if I understand correctly, the Librem15rev2 is equipped with a combo port for audio, and I got my headset working with a Y-cable splitting the combo port into a headphone and microphone connection.

Now I would like to use the microphone connector to record an external audio source (e.g. with audacity), but I just can’t get it to work!

There some source on the web that suggest this should be dead simple (e.g. https://gordonlesti.com/digitize-a-cassette-tape-with-linux/), but in my case, audacity only displays what I would cconsider as random noise.

I have the ‘pavucontrol’ module installed , and I also fiddled with QjackCtl (drawing inspiration from the guide by François Téchené “Your own music studio with JACK, Ardour and Yoshimi” in the “News&Events” section), but there is no way that the external audio source is recognized. At least I don’t get it to work.

Anybody has any suggestions?

Stefan


#2

In caae you never used audacity… Did you enable Start monitoring audio input with the drop down arrow? (I apologize as is the equivalent of asking if your computer is plugged in LoL)

Maybe an earlier version of audacity is on order?. They broke it on Ubuntu when I upgraded my OS.

If my answer is too simple, I offer my apologies to you ahead of time.

BTW does/can/should the Librem run ALSA for audio, the way Ubuntu can? (shows what a non tech expert I am)

Or… Is the issue likely with the plug situation you have… Aka do you need some kind of USB mic?


#3

PS my experience with ‘new’ upgrade of Ubuntu was just to 16.xx LTS on a desktop. But definitely it is not as good as 12.04 LTS.

Anyone have any advice on Ubuntu, whether the new releases (18?) might be better than 16.04 LTS, because I kind of hate it. :sob::sob::sob::sob::sob:

(post was edited for dumb autocorrect keyboard issues)


#4

Also out of curiosity… Would something like the Zoom Digital 4 track recorder (H4 and/or newer model) likely work for bringing in audio to a Librem, the way it is supposed to function on Windows or whatever? (obscure device, possibly not an answerable question)


#5

Hi,

it maybe that I am missing something in Audacity, but I also tried Ardour, and also couldn’t get it to work.

But I have never worked with these programs before, so maybe I got it wrong.

And maybe there is no Combo-port on the Librem15rev2, but I think in this post there was a layout sketch which seemed to suggest this:

(But unfortnately the “specs” figure doesn’t load anymore. I think this figure is very important and instructive, but I didn’t print it at the time, so maybe one could bring it up again, please?)


#6

The headset jack in the Librem 15 is not combo. It is only out. I found this out the hard way! You will need to use a USB input for your audio.


#7

I am quite positive now that on the Librem15rev2 it is combo. At least I can connect a headset via an Y-cable and scratching the microphone of the headset in a skype testing call gives a clear signal (as does speaking).


#8

Turns out I did print the figure! Here it is:

So here it says “combo Jack or standard headset jack”. But I think this is for Librem15rev2 (the one I got). Might be different for other revisions.


#9

OK,

a it seems a standard headset-jack has only a mono microphone input, even if the connector on the headset is a stereo one. I can record now, but only in mono. So I will get me a dedicated USB-Audio interface, and for the moment re-activate my old macBook Pro which has a dedicated Audio-In port.

Any suggestions for a Linux-proven USB_audio interface?

Oh, and yes, I think the Librem runs ALSA (PureOS is debian-based, like Ubuntu). At least in Audacity, the Audio Host I configured as “ALSA”, and I can invoke the “alsamixer” program and control input and output volumes with it.

The Zoom H4n recorder can be used as a 2-in/2-out audio interface via its USB port, and according to this post http://zoomforum.us/viewtopic.php?t=7826 , the Zoom H4 has 100% compatibility with Linux.


#10

I have a couple of zooms… The H4 and the newer version of it… I have not yet tried either as an external USB mic tho. Good to hear it can work with Linux tho.

Is expensive… But if u can find a zoom h4 on ebay, it works as a multitrack recorder with no latency (in case you want to make music recordings with overdubbing etc)… Plus has built in effects and distortion and reverb etc. (when used in stand alone mode, not as a USB sound capture device.

The microphones are phenomenal quality… It can mount on a tripod, and the mics are directional… So as to pick up what you want instead of the sound of a computer or a fan.

If u wanted, I would test out my H4 with Ubuntu for you and see how it works. Even if just to verify that it is a good usb mic.

In stand alone mode, it records at better than cd quality… Without any hiss. And the mic is the best I have owned.

I am imagining that your run of the mill generic USB mic will be kind of like using a phone headset… Maybe not able to get the range of sounds you aim to record?