Jam music online with Jamulus
Updated: Feb 23
Introduction
Jamulus is a tool to enable music jams and band practice online, when musicians cannot be in the same room.
With the need for social distancing, many artists and bands lost the ability of jamming or rehearsing together - unless they are living under the same roof. On a separate article, we've looked at all possible alternatives to achieve an online jam with reasonable latency.
In this article we will detail more specifically how to configure Jamulus, one of the most promising tools for that job.
Jamulus can be downloaded from this link and is open source, ultra lightweight, and can achieve relatively low latencies if musicians are close enough and the Internet conditions are favourable.
Note: the article was originally written for Jamulus 3.4.4. There is a more recent release, 3.5.1, and the differences are discussed further down in this article.
Equipment
Of course you will need a computer running Mac, Windows or Linux, and a fast internet connection. According to the developer the typical bandwidth in/out is about 150-250kByte/s with 3-5 people, so of course slow ADSL or dial-up won't cut it. You need fast broadband, NBN if in Australia, cable, fibre or equivalent.
Extremely important: get your computer close to your router and connect via Ethernet. Do not use WiFi as this will make the latency even worse and cause additional audio issues.
Apart from that, you need an audio interface, your instrument and/or a microphone.
If you don't have an interface my recommendation is the Focusrite Scarlett Solo.
Installing
Just follow the link above and it will take to the main Jamulus page on Sourceforge. You will see that Mac, Windows and Linux are supported. Follow the download link at the top and it should download the correct package for your OS. I've tried installing on both Mac OS 10.14.6 Mojave and Windows 10 Home and it was quite simple. Just click on the downloaded package and follow the instructions.
Configuring as a client
Most musicians in the band will configure and run Jamulus as a client, and look for an existing server, or a server set up by the most tech minded individual in the band. The GUI is very simple, it contains controls to pan your output if the audio is stereo and adding some reverb. Also light indicators that will inform if the delay is too high (normally way above 20ms or so) and if there is a buffer under-run.
There are three checkboxes on the left hand side:
Settings (equal to Preferences from the top menu)
· Device:
This is your sound card, the sound card where your instrument is connected.
Note that only two channels are allowed per user therefore if you want guitar and microphone, your guitar will have to be mono.
Input Channel Mapping: If your sound card or audio interface is multi-channel, there will be a drop down under this setting where you will be asked to map the left and right channels to two of the inputs of your device.
In my example I was using a Line 6 Helix in stereo, two analogue outputs connected to the inputs of my Universal Audio Apollo Twin
A simpler example would be using a Focusrite Scarlett Solo or equivalent, and just map the instrument input, the microphone, or both.
If you want to shape your guitar sound before going in, you need to do this externally. So connect using an external modeller or multi-effects like I did, or mike your amp.
There is no talkback microphones, so those who don't hook up a mike for sining will have to communicate via the text chat provided with the tool
Output Channel Mapping: where you want to listen to the output, so the sound card channels where your speakers or headphones are connected
Note: it is possible to use separate devices for input and output, minding the extra latency. The 'Device' drop down lists all options available
· Buffer delay
Aim for the minimum (128) which in my case results in 5.33 ms delay. Higher values only if experiencing serious glitches in the audio, but then latency will increase as a consequence
· Jitter Buffer
Leave in auto
· Misc
Audio channels: use mono unless really necessary or connecting instrument plus microphone. Less channels, less processing, smoother experience.
Audio Quality: start with normal, try 'high' only if normal is really causing problems on the session. The trade-off will be latency.
New client level: leave at 100%
You can turn off the fancy skin
Central server address: leave default ticked