Answered

Setup and Input lag. HDMI, 4k Projector, SPDIF, and a computer?

  • 18 June 2019
  • 6 replies
  • 103 views

Hey, apologies if this has been asked before, I just want to check something before dropping too much money.

My plan is to use my desktop as a multimedia station with an HDMI running from my 1080ti to a 4k projector (Viewsonic PX747) and the SPDIF running to the back of my playbar. I've also got 4 Sonos one's that will be in the mix.

I basically just want to confirm that this setup won't incur any significant audio lag? I used to run the same setup, but with a 1080p monitor and every few weeks or so would run into incremental issues with lag (not sure why).

Would appreciate any comments/advice.
icon

Best answer by Airgetlam 18 June 2019, 05:06

If you're running the input into the TOSLINK as Dolby Digital (and not DTS, or any other format, which can't be read by Sonos), you should have effectively no lag. Because optical is a one way format, there's no way for Sonos to know what is sending the signal.

However, you've mentioned 4 Sonos Ones. With the PLAYBAR, you can set up two of them as surround speakers with the PLAYBAR, and because they connect across a 5Ghz channel, they'll be in sync. However, the other two speakers will have to be set up as another room....which means that the signal now has to be buffered, and there will be that 75ms lag between the room that is the PLAYBAR, and the room that is the stereo pair of Sonos Ones.
View original

6 replies

Fully understand. As long as there is no perceivable delay in the same room, I have no issues.

Appreciate it
-Ryder
If you're running the input into the TOSLINK as Dolby Digital (and not DTS, or any other format, which can't be read by Sonos), you should have effectively no lag. Because optical is a one way format, there's no way for Sonos to know what is sending the signal.

However, you've mentioned 4 Sonos Ones. With the PLAYBAR, you can set up two of them as surround speakers with the PLAYBAR, and because they connect across a 5Ghz channel, they'll be in sync. However, the other two speakers will have to be set up as another room....which means that the signal now has to be buffered, and there will be that 75ms lag between the room that is the PLAYBAR, and the room that is the stereo pair of Sonos Ones.
Thanks Bruce, this is very clear.

Just one final confirmation, the fact that the signals are coming from the same device/source (PC) via Toslink, but to different destinations, will the input lag on a 4k projector cause the video to fall behind the audio?
I wouldn't think that the speed of electricity (the HDMI signal) would be perceived as any difference as the speed of light in the optical signal.

But I'm still not a fan of this setup. Sonos speakers really aren't designed for this kind of use, for example that delay between the PLAYBAR room and the other pair of speakers can't be gotten around. And it's frequently been an issue for people attempting this kind of thing to get their PC to actually send a Dolby Digital signal instead of some other codec. Not to mention the issues in getting compatible optical outputs, etc.

You're stretching the envelope way beyond its design. Expect some issues of some type. I think I've covered them all, but I can't guaranty that.
Appreciate the continued clarity and honest answer.

I should have mentioned, I won't keep more than 1-2 SONOS One's in the same room as the multimedia setup, so I don't see that as an issue.
Just to be clear, Sonos One ( a pair ) set up as surround speakers for a Dolby Digital signal will not suffer delay when using the optical input.

Any other speakers will not be part of the surround system setup, and when using the digital input, will have a 75 ms delay on playback. All speakers would be in sync only when streaming music through the system as Sonos has designed.

Reply