9ms is the industry-recognised time that it takes before the brain notices that sync is out. If you have 2 woodblocks clapping and they are more than 9ms out of

9ms is the industry-recognised time that it takes before the brain notices that sync is out. If you have 2 woodblocks clapping and they are more than 9ms out of sync, you will hear one as an echo instead of 2 blocks at the same time. So if you are a band wanting to play remotely and you have 100ms network latency plus all the other latencies of the software layer, it's not going to be possible. Similarly if you are trying to drum in time with a track: more than 10ms latency from when you tap your finger to when you hear the audio, you'll have a hard time staying in sync.