[PlanetCCRMA] Confusion over JACK inputs

flump00@breathe.com flump00@breathe.com
Sat Dec 4 09:27:01 2004

I know that this sounds like a really dumb question, but I can't seem to get 
JACK applications to realise that there is any audio coming from my line 
It was working the other week, and now it has all gone crazy, but I can't 
fully remember what I have changed, nor how I got it working in the first 
place... Here is my setup:
 - I have a bass + amp going into my line-in input.
 - I am using a SBLive!
When I link up ardour to use the alsa_pcm:capture_1 and alsa_pcm:capture_2 
inputs, they don't show up on the level meter for that track.
Using Qamix, I have set up the capture source to be Line. The Line playback 
volume is at 87. I am confused regarding the Capture though, as there is a 
Capture level, and a AC97 Capture section. What is the difference? Sorry... 
a dumb question, eh? 

I am confused that I can have output coming out of my speakers with no 
latency, but applications refuse to see such input of audio. 

The other week when I recorded, there was a delay between me playing a note 
and it coming out of the speakers, obviously as it was being processed.
What is the subtle difference between the connections in JACK, and the 
patchbay? Why can't I link up individual subitems in the patchbay, only the 
parent node items? 

Anybody care to walk me through the setup, explaining each step? What inputs 
am I specifying, and does JACK use some capture setup that is different to 
the ALSA capture or something? I'm very confused.
By the way, I'm using Fedora Core 2. 

Many thanks