Been a while since I looked at other stereo gear but I don’t recall seeing any delay specifications listed.

$6500 Denon doesn’t list that spec: https://www.denon.com/en-us/product/av-receivers/avr-a1h

Didn’t see it on any of the high-end gear here either. (sort high prices first)

https://www.crutchfield.com/g_10420/Home-Theater-Receivers.html?&o=d

Denon and Marantz are both made by the same company, so would probably share components. Could be the same delay.

@Stanley_4 

Thanks for the suggestion. 
But do the specs for receivers ever list a delay introduced by the music conversion?

I don’t think I have ever seen such a delay listed in specs but maybe I’m overlooking it?

 
And while Denon is owned by Marantz (or maybe it’s the other way around) I don’t know if all receivers made by the same companies have the same delays. I would guess they do these days, but I did have an older Marantz prior to this one and it didn’t have a delay. So maybe it’s a roll of the dice. 

Ancient audio equipment used analog tone controls and had no surround processing. The modern stuff, especially surround units, are now using digital processing for almost everything. There is some processing latency associated with the digital processing. I don’t recall ever seeing a receiver give an estimate of their latency. And, the latency is likely to vary slightly, depending on the function.

Within the SONOS ecosystem time alignment is very good and predictable. The movie industry worked out their lip sync (time alignment) specs in the early 1940’s. In general the TV and audio industries don’t seem to care. I’ve been in TV control rooms and the lip sync is already skewed -- before the signal is sent out to the transmitter or cable company. Then the home TV and audio systems add their own twist.

As I said I couldn’t find it in the limited number of places I looked.

Buzz,

What you say makes sense. 
But then, my next question is if anybody has found a modern receiver that produces good surround sound and has a minimal delay? Hopefully an acceptable delay. 
 

Otherwise, what’s the point of the Port?

People just learn to live with the delay?  One room not synced with the others in the house. 
Or just making sure that they shut doors between rooms so as to not let sound bleed between the two rooms. 
 

If your receiver supports a Tape In/Out, insert PORT as if it is a cassette deck. Unfortunately, the Tape In/out has disappeared, along with cassette decks.

With SONOS there is a 75ms latency between Line-In and output from the players. All of the players and PORT’s Line-Out will be time aligned with each other. As a result, Line-Out will be aligned with all of the SONOS players and output from the receiver using Line-Out as an input could be aligned with the SONOS players if the receiver supports this. Analog output from the receiver connected to PORT’s Line-In will always be 75ms offset from the receiver.

A note from the physics department: Sound travel is pokey at about one foot per millisecond. Consider two speakers ‘A’ and ‘B’ wired to the same amplifier and separated by 30 feet. A listener at ‘A’ will claim ‘B’ is 30ms late. Listener ‘B’ will claim ‘A’ is 30ms late, while listener ‘C’ at the midpoint between speakers will claim “time aligned”. All three observers will be correct.

Buzz,

I think I understand what you are saying. 
But to make certain, are you saying I hook up a port with it connected to the receiver as if the receiver was the source?

Wouldn’t I need two ports?  One playing Tidal into my receiver and then one taking an output from my receiver and distributing it throughout my Sonos system? (Not that this is an issue, just want to make sure I understand)

But I like this concept!  Would I have degradation of the music by getting it from Sonos and then putting it back into Sonos?

Think of PORT as being two separate devices on your network, sharing the same shell — Line-In and Line-Out. Line-In can be selected as an input by any SONOS device on the network, including the Line-Out in that same shell. There is always a 75ms latency when selecting a Line-In. This Line-In can be Grouped with any combination of players. Line-Out is just another player. All Grouped players will be time aligned.

If you are Grouping speakers with Line-Out, playing tracks from your library or an online source and Line-Out is connected to your receiver, any time offset from the SONOS players is the fault of the receiver.

If Line-In is accepting analog input from the receiver, there will be a 75ms offset to any SONOS output.

So I connected the “zone 2” output (unbalance pre-outs) from the Marantz AV7704 to the input of one of my Sonos Amps. 
 

Huzzah!!! It works!

As far as I can tell, everything is synced!

Thanks, Buzz!!

What’s interesting is that at first the music coming out of my Marantz was a good half second or two ahead of what was coming out of the rest of my Sonos; the reverse of what I was experiencing before, when my Marantz was behind the rest of the system. 
It took me a bit to find that Sonos automatically sets the line-in to a 2000ms delay.  I set it to 75ms and it sounds good to me now!
I guess this means the non-Marantz music is now delayed by 75ms when compared to my Marantz powered speakers and I’m unable to hear the delay. Either way, it sounds good!

Though I will say, that it’s a bit cumbersome in managing the volume.  The overall volume is affected by the volume I set on my Marantz, the volume on the connect that is the line-in to the Marantz, and also the volume on the group that is playing the line-in from the Marantz  

It’s clunky but it works! And it’s much cheaper than setting up Roon to run my system.  You can set up delays for each zone with Roon to run a system over one’s Sonos, but they are expensive.  So consider me gruntled!