Port extenders to other analog amps

Has to be Connect ( Gen 2 ).  The Connect is only compatible with the S1 app.

The Port will work with the S1 app but if you acquire old Connects you’ll be stuck with the S1 app which could be an issue if you want to someday purchase newer Sonos products that only work with the S2 app.

And it’s harder than average to identify a CONNECT gen 1 versus gen 2. They aren’t labeled as such, and you need to rely on the manufacturing date. Search this forum for dates of each. 

Oh, to answer your questions, the Sonos Port is what it is, there is no ‘lesser’ version with just an output. 

Given that you’re going to be grouping these devices (any S2 device with another S2 device for music) there will be no delay. Any delay is handled when the music goes in…so for streaming music, you’ll have no issue, but if you’re using the input on any Sonos device (from an amp, say radio/turntable/tape deck) there will be a delay between the Sonos and the ‘normal’ speakers connected to the amp.

As ​@MoPac has indicated, any S2 device can be grouped with any other (or several) S2 device(s). 

Or, for that matter, any S1 device can be grouped with other S1 devices. You just can’t group S1 with S2 devices. For them to group, and play the same thing simultaneously, they must be the same operating system. 

For your purposes (analog output) there is no difference between PORT and CONNECT (Gen 2). All Line-Out’s will be time aligned within about 2ms when the Rooms are Grouped.

The first four numeric characters in the serial number should be 1501 or greater, else you’ll be stuck at S1.

The Sonos related delay is well covered above but there is also an internal delay in many old systems caused by the internal audio processing.

Both my Denon and Yahama AVRs had internal delays, they were different and a couple changed length depending on processing mode. Disabling the audio processing solved the delay issue.

I'd lean to used Ports over used Connects, much improved and newer hardware.