They way jack is packaged for Debian/Ubuntu, only jack2 will be able to grab the card.
For this, you only need two packages. pulseaudio and jackd2
There are no known packages on Debian/Ubuntu that will let jack1 grab the card from pulse-
<ul>
<li>a bug in PulseAudio that causes it not to give up the
soundcard when JACK asks (<a href="https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1163638">LP: #1163638</a></li>
- <li>bad package dependency information that causes a critical
- package to be missing even when JACK and PulseAudio are
- installed</li>
<li>a bug that causes JACK to freeze up when told to stop,
causing issues with restarting</li>
</ul>