[ardour-users] configuring inputs and outputs / no line-in .asoundrc

[Heikki Pernu]

Rhythm King Drums wrote:

> I am a newbie to ardour and jack.
> My system starts and runs / records, sometimes output is scratchy 
> sounding.

Do you run jackd with -R flag, that is with realtime privilege?

> Is the .asoundrc file capable of configuring sound card to include 
> mic-in, line-in? Are there .asoundrc templates out there somewhere?.

I would be interested in more detailed information about asoundrc too.
However, I do not think you actually need asoundrc for the task you 
describe here.
There are some templates available at www.alsa-sound.org, though.

> I am a little scratchy on the input / output thing.
> Ardour does not seem to see any line-in. Mic is plugged into line-in.
> I can only record from pcm and output to pcm.
> Alsamixer has no affect on recording level nor does slider in ardour.

> I have used built in intel8x sound card and aureal vortex with same 
> result.

These both are 'consumer' audio cards(especially the first one) in the 
sense that you can
only record from a single source at the time.

The source of recording is chosen at runtime by alsamixer or other 
similar software.
You can usually change it between various hardware inputs 
and/or(possibly) the mixer result channel.

In the case of intel8x sound card (which is the same driver as used for 
NForce audio) you can
change between various hardware inputs.

The selection is done by selecting one of the inputs as 'capture' 
device. In alsamixer, this is
done by pressing space on the channel you wish to select as capture 
source. Only those channels
with '---' can be chosen as the recording channel. The change takes 
effect immediately and affects
all software.

To set the recording level, you usually set the 'Capture' level to 
something sensible from alsamixer.
The actual level on the respective channel might only affect the output 
of the mixer(the line out) but
not actually increase the recording level(but I'm not sure about this). 
Check that you do not have
mute on on the capture channel which is usually the default.

If you are using microphone, you should propably use mic in, set that to 
recording channel, and set
Mic boost +20dB on. The mic input is the only one which has the 
circuitry to feed power to the
microphone. Without it you won't hear anything.That does depend on your 
microphone, however.
If you use a typical PC microphone, then you'll have to connect it to 
mic in. A separate microphone
with a battery container will not need power from the computer. Or if 
you are using a professional
microphone with phantom power fed by a mixer. Are you sure you can use 
the microphone
in the line in connector?

The fader in ardour does not have any effect on the actual recording 
level - it only determines the
relative output level compared to other tracks in ardour. This is the 
same as in conventional mixing
desks. The analog gain of the hardware input channels is determined by 
alsamixer, if any.

Otherwise, if you need multichannel hardware input, you'll have to 
invest in something else than
conventional consumer soundcards, or record one stereo track at the time.