What volume control dB numbers mean, soundbar HDMI-ARC and HDMI-eARC follow-up (Week 32, 2023)

Sound Advice
By Don Lindich

Week 32, 2023

Q. When I turn up the volume on my stereo receiver, the display says the decibel reading goes down, like -12 to -6. Do you think it was wired backward?

-E.A., Minnesota

A. It is working correctly. When you turn up the volume the display is show how many decibels of volume remain. So, if the display shows -12 dB, then you have 12 decibels to go before the receiver is operating at its max. In a home audio receiver, you can go into the positive but if the system is set up correctly then 0 dB on the display will duplicate the playback volume you would experience in a movie theater.

Soundbar HDMI follow-up: Last week I described the different connection possibilities when using a soundbar with an HDMI ARC or eARC input. This week I will discuss my sound and picture quality findings using a 75-inch Samsung Q90R television with a Samsung HW-Q90R soundbar. Both were Samsung‘s top-of-the-line in their respective categories and still perform well today. Both were purchased in late 2019 (just in time to wait out COVID) and are currently in use in my living room.

Samsung televisions use the Tizen operating system, which is based on Linux. One of the reasons I have spoken favorably about Roku is there are so many channels available. Some of these channels I could not find on Tizen, so I purchased a Roku 4K Ultra streaming box so I could still watch them.

I started by connecting the Roku Ultra box to one of the soundbar’s two HDMI inputs. I then streamed content from Disney+, Hulu and Netflix using both the TV and the Roku, comparing the sound and image quality. I was surprised to see that using the television to stream the channels provided notably better picture quality, with deeper color and a sharper image. If you did not have both available to compare it is unlikely you would have found fault with the Roku, but comparing them back to back the difference was apparent.

I then connected the 4K Blu-ray player to the TV, using the HDMI ARC connection to send the audio from the television to the soundbar. Previously I had to manually switch the Roku and the disc player cables because the soundbar only has two inputs, and my satellite box was using one of them. By connecting the player to the TV and routing the audio back to the soundbar I could avoid this switching. The picture looked the same, but I found the sound quality took an unexpected nose dive compared to connecting the player directly to the soundbar. I checked all the settings to confirm what I was hearing, and the sonic difference was even more obvious than the picture quality difference between the television and Roku.

My current configuration has the Roku connected to the television and the disc player and the satellite box connected directly to the soundbar. Whenever I can I use the TV to stream the content, and for the few channels I don’t get with Tizen I use the Roku box. This provides the best possible picture and sound quality in all situations. If you have a soundbar or receiver with multiple inputs, try connecting your disc player directly to the audio component and the TV and compare to see what provides the best sound quality. (My money is on connecting the player directly to the soundbar or receiver.) The second is that at least with Samsung televisions, you get the best picture quality using the TV as the streaming source rather than an external component.