ive seen these suggested levels in two publications now
• 85 dBC SPL for each screen speaker • 82 dBC SPL for each surround array • Approximately 91 dBC for the subwoofer*
this is the smpte recommendation
https://www.smpte.org/sites/default/files/2013-03-12-Standards-Cinema_Audio-Vessa-v2.pdf
is anyone setting levels like this in their home or setting all speakers to the same db level?
why or why not?
The distance between one or several central listening positions in a home theater and all the speakers must be measured manually or determined by automatic software. They may be similar for the front three channels, but they are rarely the same for the various rear channels. It all depends on your room and your furniture arrangement. Once the receiver knows these distances, it adjusts things so sound from all speakers arrive at the central listening position simultaneously regardless of the distances. Often new HT owners ignore this, and that's a major reason why the automatic systems were developed.
Similarly, volume levels are adjusted so all channels are the same volume – as a start. From that people are free to adjust various channels as they wish. I often see people new to HT have their surround speakers and subwoofer boosted too loud. With time, they usually readjust so these speakers blend in better.
Unless your room at home is identical to movie theaters in length, width, height, and seating-to-front speaker distances, you should ignore what others use for settings. That's why all AVRs or prepros come with manual or automatic systems.
If you adjust things manually with a SPL meter, it doesn't really matter what dB level you choose to adjust to, as long as they are the same. In my home, I found 75 dB works well enough so that noise from the refrigerator in the kitchen or the AC ventilation don't interfere with the meter while I'm doing the adjustments.
