I’m going to show an easy way to measure round-trip latency using your audio interface and Debian Linux.
What is round-trip latency?
Round-trip latency is the time it takes for an audio signal to enter the input of a device, get processed by your PC, and exit the output. I’m going to show an easy way to measure yours using Linux.
Measuring round-trip latency
0. Connect the input to the output of your audio interface.
1. Install Jack 2 and Qjackctl.
sudo apt install jackd2 qjackctl 2. Configure Qjackctl.
3. Start Jack and open the graph.
4. Open a terminal and start jack_iodelay.
5. Connect the capture and playback ports to jack_iodelay.
6. See how your interface compares to others tested for Interfacing Linux. You can find firewire and PCIe benchmarks here.
Latency hack
USB ports connected directly to the CPU (usually) have lower latency. You can find this information in your motherboard manual.
