The protocol also adds HDMI CEC, which allows you to control HDMI-connected devices with one remote control.
This connector allows audio signals to travel to and from the soundbar and eliminates the need for a secondary cable to send audio from your TV back to your soundbar. It's a protocol introduced as part of HDMI version 1.4 in 2009, and since then, has become a somewhat common addition on soundbars. HDMI ARC stands for 'Audio Return Channel'. We're currently working to address this issue. Unfortunately, most of our test results could be off by potentially +/- 16.7 ms. As a result, it was missing the 'ball on white bar' image that we use to measure the latency accuracy.
Note that our Reaper software was skipping frames, as its project settings were set at 30fps instead of 60fps. Lastly, your equipment, like the device you're using to watch and listen to this test video, could have latency in itself and could change the perception of the video. Some apps and devices also compensate for latency, so your experience may vary.
Other factors like TV input lag fluctuation can influence latency. However, if this test is performed multiple times, the difference is approximately 4-6 ms, which isn't very noticeable. That said, latency results can vary depending on the frame synch between the 60fps YouTube video we use and our 240fps recording speed.
Notice that in the ARC and Optical results, the ping sound is audible only after the ball moves away from the platform. This indicates a high positive latency. The Vizio M-Series M21d-H8R has a disappointing latency performance. For example, if you're watching a movie, you'll more likely notice the actor's voice before their lips start moving. When the results are more (or less) than -55 ms to 75 ms, you start to experience noticeable latency. A negative latency value indicates that sound comes before visuals. A higher positive latency value is more acceptable than a higher negative latency value, as it's easier to notice sound coming before visuals than the other way around.
A positive latency value indicates that the visuals come before sound. Conversely, this same soundbar has -85 ms via its Full HDMI In connection. However, as hinted above, latency can be measured in both positive or negative values. For example, The Vizio SB36512-F6 has an ARC latency of 75 ms. We measure latency in milliseconds (ms), and we consider a good latency value to fall between -55 ms to 75 ms. Our video is slowed down to 20% to more easily see the sound delay. At the same time, the left circle should alternate between green and white while the red circle on the right side appears. Each ping should ideally be in time with the moment the white ball touches the moving white platform at the bottom of the screen. In this video, there's an audible ping that occurs once every second. We then play the audiovisual latency video seen down below on the TV and record the process. A tripod with a camera phone is set up approximately 5.75ft away from the TV to film the results. We connect the same Samsung Q80T TV with the desired soundbar and wired connection, so the results are comparable. The Latency test refers to the latency over three wired connections: ARC, Optical, and Full HDMI In.