Latency of the system

A digital system always has some latency. On a forum, someone questioned the use of digital mixing desks because of the latency that is added by the system. Although my experience tells me that the latency is really small, it is always a good idea to measure it.

For this test, I downloaded the 'test tone generator' software an ran this from the tablet. The headphone-output of the tablet is split to two XLRs: one going in the IDR32, the other going in a two channel USB pre-amp. Then, a cable is connected between output 1 of the IDR32 and the second input of the USB pre-amp. Using Audacity, it is possible to capture the exact delay added by the IDR32.


The latency turns out to be 1.2 ms (or 53 samples at 44100 samples a second). This is equivalent to time it takes sound to travel 41 cm through the air. I think this latency is very acceptable for live sound, but things might be different when using in ear monitoring.


(BTW, the gain of the pre-amp was not matched, this is only a test on timing).