jackd1 software package provides JACK Audio Connection Kit (server and example clients), you can install in your Debian 8 (Jessie) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install jackd1
jackd1 is installed in your system.
Make ensure the jackd1 package were installed using the commands given below,
$ sudo dpkg-query -l | grep jackd1 *
You will get with jackd1 package name, version, architecture and description in a table
| Distro | Debian 8 jessie |
| Section | Sound |
| Package | jackd1 |
| Version | 1:0.124.1+20140122git5013bed0- |
| Description | JACK Audio Connection Kit (server and example clients) |
| Sub Section | Sound |