If you are a musician looking to jam out with a friend, you should be able to achieve under 40ms of latency using VDO.Ninja if both you and them have a good Internet connections. This implies being directly connected via wired Ethernet with low packet loss, rather than via Wi-Fi or cellular.
Quick start with &lowlatency
The easiest way to achieve low latency is using the &lowlatency parameter (aliases: &ll, &ultralow), which configures multiple optimizations automatically:
This single parameter disables audio processing (echo cancellation, auto-gain, noise suppression), sets optimal packet timing (10ms ptime), minimizes buffers, uses constant bitrate, and bypasses the WebAudio pipeline.
Manual configuration
For fine-grained control, here's a manual example of settings optimized for low-latency audio-only two-way communications. I find most of the latency with a setup like this is outside the scope of VDO.Ninja; so the sound card settings, the capture device, how far away I am from the mic / speakers, etc.
&aec=0 disables the echo cancellation; this implies we will need to use headphones
&agc=0 will disable auto-gain, which is preferable if streaming music
&denoise=0 will disable the noise filter, which is ideal with music applications.
&ab=16 gives us a constant audio bitrate of 16-kbps. Consistency will ensure more reliable latencies, and 16-kbps is so light-weight it shouldn't be boggled down on bad connections. You can increase this value depending on the audio fidelity that you want, but higher could introduce more latency.
&enhance, &ptime=10, and &maxptime=10 are advanced settings, that tell the system to prioritize audio packets and limit their size to 10ms. This is the lowest we can set them using a browser, but it might be possible to go lower if using something like the Raspberry_Ninja hardware project that VDO.Ninja has available for advanced users.
&novideo disables video, which can make a big impact on latency, as not streaming video will free up a lot of bandwidth, but also not force the audio to stay in sync with the video. You can send the video in a second tab/session if needed, and that way, it won't try to stay in sync.
&noap just disables any of the advanced web-audio processing, such as compression, gain, level-meters, and panning. This will free up some milliseconds of latency in some cases,
Without much effort, you should be able to achieve 40-milliseconds of latency, or less, with this setup. Achieving between 20- to 30-ms is feasible in cases, but expectations of under 20-ms will require significantly more investment.
For playback on Windows, consider using the Electron Capture app which now supports ASIO audio devices, providing even lower audio output latency compared to standard Windows audio.
