Feedback During Playback

Installation & Configuration Linux
#1

Now that I’ve added a 50MB SCSI disk and no longer get messages about
the disk not being able to keep up with Ardour, :slight_smile: I’ve been able to
record to Ardour 2.0beta10 with no problem… however, now I’m having
a problem with feedback and an echo when playing the recordings back.
Here’s Ardour is set up:

Two mono tracks (which aren’t truly mono - a bug?) labeled Left 1 and
Right 1:

Input for Left 1: alsa_pcm:capture_1
Output for Left 1: ardour:master/in 1

Input for Right 1: alsa_pcm:capture_2
Output for Right 1: ardour:master/in 2

Input for master (in 1): Ardour:Left 1/out 1
Input for master (in 2): Ardour:Right 1/out 1

Output for master (out 1): alsa_pcm:playback_1
Output for master (out 2): alsa_pcm:playback_2

Tape deck into two channels of the mixing console

Soundcard output into two channels of the mixing console

Mixing console master output into soundcard input

What am I doing wrong? Before, I wasn’t having any feedback problems
before with ardour 0.99.3, which, if I recall, was configured similarly
by default for two channels. Thanks for any advice that anyone can kindly provide!

#2

First of all, you can make truly mono tracks if you want. Just remove the second output from the track and it’s a true mono-mono track.

Your jack connections look correct. Maybe you have your soundcard mixer set up to capture the PCM output of the card?

#3

Thanks for the help! I’d overlooked that I had the monitor level up in the soundcard’s mixer. Doh! :slight_smile: That problems’s now solved, however, there’s still a problem with playback, which I’ll go into in more detail in another message; only getting mono back out, not stereo.

#4

It turns out that the stereo/mono problem is either an ALSA problem or
else a problem with the ALSA driver for
my Echo Mia-MIDI sound card. The left
channel can be adusted, and affects only the left channel, but the right channel from ALSA goes to both channels
of the soundcard and can’t be adjusted.
The problem exists only with ALSA, not
OSS. Has anyone else experienced this problem?