Hi Mark,
I just use this:
ecasound -c -i:jack -o:some.wav
When ecasound (version 2.4.4 here) starts I connect it in QJackCtl. I
enter 't' at the ecaprompt to start recording, 's' to end it, 'q'
to
quit the program. That's for quick & easy simple recording.
Best,
dp