by Prof. Dr. Alexander Carot

Since the year 2005 the Soundjack software has been the result of Alexander Carot's musical experience and research activities in distributed music on the Internet. Once you are familiar with a few basic pinciples related to audio streaming on the Internet it will provide you the best possible quality- and delay conditions in order to play live music as shown in the videos below. However, you need to realize that the final latency depends on the physical distance, network capacities, the actual network conditions and the actual routing between the involved peers. In most cases real musical interaction is limited to physical distances below 1.000 km. It is important to understand that latency acceptance thresholds vary from player to player and furthermore decrease with an increased performance tempo. Altogether the objective judgement about the feasibility underlies a complex process. In that context Carot recommends reading the papers below or his final thesis here.

For further information do not hesitate to contact the author via email or meet him in the Soundjack chat below.

Download Soundjack (current version of January, 10th 2014):

New since last update (nothing special for now) :

1.) The Soundjack server has found a new location in the US
2.) This is the very last official Soundjack version - the next update will be based on a novel concept

Still existing bugs/issues:

1.) Linux: Jack still buggy
2.) Linux: Casual soundcard issues can lead to white noise - restart required
3.) Winodws: Either your card has to have native ASIO support or ASIO4ALL must be installed (WASAPI might be an alternative)
4.) Windows: When using ASIO4ALL *any* other sound application (incl. Windows sound notifications) must be turned off

Soundjack Mac (built with OSX-10.6.8-64-bit)

Soundjack Windows ASIO (built with Win7-32-bit)

Soundjack Linux (built with Ubuntu-12.04.1-32-bit)

How to use Soundjack

Once you launched Soundjack you first have to make sure to have a properly working soundcard configuration ! In that context check the available input- and output devices and configure them with the supported channels and audio buffer size. If the settings not ok the lower play and record buttons will be disabled and the the number box will remain red. In this case you cannot proceed further and need to reconfigure your settings. If they are ok the buttons will be enabled and the box will show green color. Then you can choose between two modes - the automatic server based mode (1) or the manual p2p mode (2).

(1): In automatic server based mode type a username into the edit field and hit enter. In the third line you see your own entry uploaded to the network. Below the second line you see other users currently online. If you want you can use the text field as a simple chat. The second line "Group Connection" is supposed to work for large music ensembles of more than 4 players. In this mode every incoming stream is mixed at the server and sent to every connected user. This stream is an uncompressed one-channel stream with a block size of 512 samples. The group connection is currently in debug mode, which is why it is often disabled. Furthermore, if you choose "private room" you can define your own "rehearsal space". Players who choose the "public" option or simply chooose a different room will have a disabled ON-Button

(2): In the manual mode you need to specify the desired IP addresses and ports yourself. This is especially useful for scenarios, in which you want to connect machines within a local area network (LAN). In this mode you do not appear in any other person's userlist.

Finally, in order to establish a successful Soundjack audio streaming connection you simply need to hit "ON" behind the respective user in the userlist. If it doesn't work you are dealing with firewall issues or a symmetric NAT, which is not suported yet. In that case you should ideally enable your router's portforwarding to port UDP 4401.

Additionally there is a forum/chat, which you can access via: Soundjack Forum/Chat

Locations of visitors to this page

Selection of our international publications about distributed music

2009 External latency-optimized soundcard synchronization for applications in wide-area networks, AES Convention, Tokyo, Japan
2009 Towards a comprehensive cognitive analysis of delay-influenced musical interaction, ICMC, Montreal, Canada
2008 Workshop Paper Tonmeistertagung Leipzig, Germany
2008 Audible ICMP Echo Responses for Monitoring Ultra Low Delayed Audio Streams, AES-Convention, Amsterday, The Netherlands
2007 Network Music Performance-Problems, Approaches and Perspectives MITGV-Conference, Budapest, Hungary