Since any Sonos device can be grouped with any other at any time, the delay is going to be there regardless of the grouped status.  There really is no concept of “single use”, because a “single use” can become “grouped use” with a mere click.  

@tatoj 

The important question is… „a delay between what“. As you said a computer and other sources are mentioned as possible AUDIO sources. So using the pc as an audio source won’t be a problem though there’s the 75ms delay between input and output caused by AD converting. 
Stereo partners or grouped rooms always will play synced. 
BUT if you use the pc as an video source, there will be a delay between video and audio output. Besides this is the only reason because Sonos analogue input isn’t recommended for tv even if it just outputs stereo. 

Analog to Digital isn’t really the reason for the delay.  it’s the buffering need to keep wireless speakers in a multiroom audio setup in sync.

It‘s both… the minimum delay of 75ms that always exists is caused by the AD convertion and a minimum of buffering. If you use the „audio delay in groups“ option, the buffering time will increase. On top there could be a delay up to 2 seconds, if audio compression is active set manually or automatically. 
So IF analogue input is the only option for video content, you have to deactivate audio compression and set audio delay for groups to minimum. Maybe the 75ms are ok for some users. 
Really no delay as with Sonos HC products only can be achieved by using digital input (means no AD converting) and using no buffering. 
The missing buffering for digital input that produces an echo on grouped rooms can be eliminated by using „tv dialogue sync“. Imho this option produces a minimal buffering. 
 

No, it’s not both.  The delay is for buffering and buffering only, and is necessary for syncing between rooms.  The AD conversion is instantaneous.  

@jgatie 

This was my information from Sonos stuff… i don’t know how much of the 75ms is buffering or converting, but imho there must be some part of this time for converting because every technical documentation i found says that it can’t be done without minimum delay. 
But however it’s called… important to know is that for analogue input there is this minimum delay and that it has an effect on video sources and for using classic hifi amps bonded with speakers if they are integrated to a Sonos system via Sonos port or connect without using a pre out connection. 
But that’s a different story… 

I agree that buffering may be the bigger part of the delay. 

I don’t know where you got that info from (“Sonos stuff”) but it is not correct.  The delay has nothing to do with analog to digital conversion, it is for buffering only.  Also, the TV input has minimum delay because it is used exclusively to send the sub/surrounds signal over a dedicated one-way 5 GHz connection to a sub and/or speakers in the same room.  This connection cannot be used for music because grouped rooms can be anywhere in the home and the signal must pass through walls and floors to get there.  Since the low latency 5 GHz signal isn’t strong enough to pass through walls/floors, music is transmitted between rooms via the buffered 2.4 GHz connection.

Yea I’m worried about lip sync issues.  My computer is a multi use device, and while sometimes it’s music where lip sync doesn’t matter, other times it’s youtube or netflix where a lip sync issue will be a problem.  That’s why I mentioned since they have specifically listed computer as a Line-In feature now, I wasn’t sure if anything was different with the ERAs.

That’s why I was curious if a single 100 (not in a wireless pair, not grouped to other rooms) would be even lower than 75m since there’s nothing to buffer/sync up to, just direct audio to one speaker.

From Sonos:

A quick note on Play:5, Five, Connect:Amp, Port, Connect, Era 100 & Era 300

While it is possible to use these players with a PC by connecting to their line-in ports (Era models will need the USB-C adaptor), this isn’t a recommended solution if you’re planning on doing something that requires audio/video synchronization. There will be a minimum of a 75ms delay on the audio due to the signal processing performed on the line-in side. If synchronization isn’t an issue for you, you can simply connect the device to your PCs headphone or line out jack like you would a pair of regular headphones.

There’s no such thing as a “single 100”, because at any time a “single 100” can become a “grouped 100”, which would require a buffer.  There’s no way for a single 100 which is not buffering input to become a grouped 100 which is buffering input, unless the audio is stopped in order to build up the buffer.  Audio stoppages when grouping are not good for business, especially for something sold as a multi-room music system, so the buffer is there, single use or not.  

If you google “analog to digital converter latency” you’ll see a bunch of sources (none of which I want to link to from here) all stating that while it’s not absolute zero, it’s well below what humans can perceive..   So buffering is the bigger part of the delay compare to ADC, in the same way that the Sun takes up the bigger part of the mass in the solar system compared to Pluto.

Some people notice the delay and some people don’t.  In the past, it has bothered me, but I recently tried connecting Era 300s to TV via bluetooth, and was not bothered by any lip sync issue.  That TV isn’t used for ‘serious’ TV watching really, so I think it will be fine in that case.  I would not use it for movie watching or anything like that though.

I just would not count on using Era 100/300 for external sources in sync with video. If it works well enough via line in or bluetooth, then consider it a bonus feature.  If not, enjoy the Era speakers for their intended use.

So if I only pay for one Era 100 at Best Buy I can walk out with seven of them because there is no such thing as a single?  Sarcasm aside I understand what you’re saying, I guess I just think it’s not ideal that the software will buffer even when not grouped.  I completely understand the need for a buffer to sync things up wirelessly/across rooms … which isn’t required with one speaker, even if it can become more.  Just because it “can become a group” doesn’t mean “it is” grouped.  As I stated, I understand this is how it worked before, but since the ERA 100 product page specifically mentions computers with the Line-In I thought something might have been re-engineered on the software side when it recognized use with the USB-C Line-In adapter.

@tatoj 

I completely understand your point of sight, but imho the system would become very instable if there are too many options for using a speaker this way or that way. Sonos has got a concept for the whole system and so there are special products for using Sonos with video content. 
I think using a Sonos Ray also would be a good solution to work with a computer. 

Line-In and speaker output are two separate devices on the network sharing the same shell. There is always a 75ms latency for Line-In. This is really more than a simple buffer because it affords some time for SONOS to repair the system’s network topology if the network develops an issue. 
 

While reading email or fetching a web page, a minor network stall of a few milliseconds is no big deal, but would be catastrophic for music. 75ms allows enough time to work through most of these issues. Actually there is a buffer that can be many seconds of music. You can explore this by breaking the Internet or NAS connection while music is playing. In many cases music will continue till the end of the track. (No guarantees)

@melvimbe 

I like your comparison to sun and pluto.  I read some articles about audio AD converting and there can be different results of time critical output. But i absolutely agree that the delay is much less than the buffering time. I just was used to call this „caused by AD converting“ because on the german community it always was communicated this way. But learning never stops and so from today i will call it more correctly. 

Let’s say  the line can play without delay, hypothetically.  Say you got the Era 100 in one room and a Five (or whatever) in a second room.  You start playback from line in the first room from the computer with youtube and it plays in sync.  Say you decide you want to group in your 2nd room….what should happen?  Do you want the two rooms to play in sync, but be behind the youtube video?  Or do you want the 1st room to play in sync with youtube and the 2nd room be out of sync? (which is what happens with TV audio)   There in lies the issue.

Now say you have a turntable connected to the line in.  You don’t care about a buffer since there is no lip sync concern, but you have the Era 100 set to play immediately.  When you group, you now have a problem with syncing...that doesn’t exist in how Sonos works today. 

Anyway...why don’t you consider getting a Sonos Ray insted of an Era 100?  The Era 100 + line adapter is $268, while the Ray is $279.  The Ray would not have any delay and should give better audio than an single Era 100.  You’d be losing bluetooth and voice control, but that’s about it I think.

As soon as a second speaker is added/paired wirelessly or another room is grouped, it should jump to the 75ms buffer, to keep them in sync.  I just don’t get the need for the 75ms buffer if you’re only playing to a single speaker wired.  There is no need for a buffer to sync or “repair the system’s network topology if the network develops an issue” as buzz said if you’re not playing over the network.

In the past I explored the possibility of using a Play 5 with a computer but I abandoned the idea after learning about the latency issue.  I was only questioning now about the ERA 100 because Sonos own marketing mentioning computer with the new USB-C line in adapter.  I thought it could mean something was re-engineered to be able to use these with a computer in a way the previous Line-In’s could not.  I have yet to find a review of someone using these with a computer, so I decided to ask here.

To be clear, I would not have enquired at all it Sonos themselves didn’t mention computer in the new marketing material.  If it wasn’t mentioned I would have assumed it worked the way it always has.

I have a Gen1 Beam I hooked up to my computer as a test when I first purchased it.  I didn’t love the setup.  A Ray might work better as it’s a smaller footprint but the Beam lacked some low end with music, so I assume the Ray would be worse.

That ‘jump’ would result  in every sonos room in your room stopping for  75ms at a minimum, every time you add a speaker to your group.  That’s not what you want in a multiroom system.  Also, what happens when you remove the rooms from your group, and could theoretically play without the delay again.  Should the system just skip over 75ms of the audio to get caught up?

I agree that that was bad marketing. Not entirely untrue, but better left unsaid.

And to be clear, I don’t think anyone has a problem with the question.  It is a good question, I just don’t know that having the latency added/removed dynamically when needed for grouping is the best idea.

I have not seen the frequency response for Beam or Ray.  I believe Era 100 is a slight improvement over the Sonos One.  Peter Pee on youtube might be a good place to see that info, not sure.  Regardless, all of those options will do better with a Sonos Mini added, if it’s in your budget.

I understand, but I wouldn’t be using this in a multiroom setup.  My only point was IF you’re using a multiroom setup, I understand the 75ms minimum.  IMO, any Line-In’ed speaker that isn’t paired/grouped shouldn’t be subjected to the same 75ms because a sync/buffer isn’t required since it’s not in a group and not being used over the network.  So yes, if for some reason it was grouped, then removed from the group, it would play without delay again.  I’m not saying the delay needs to be 0, but should be less than 75ms, maybe in the low 20s.

If I bought an Era 100, it would be used with Line-In and left alone.  I wouldn’t be constantly adding it and removing it from groups.  It would serve one purpose and be left alone to function.  I still may purchase one to test with at some point, unless I can find a review of the Line-In functionality.  All the YouTube reviews I’ve seen didn’t have the Sonos Line-In adapter at the time of filming so no one commented on the Line-In latency.

Your anecdotal usage isn’t a justification for taking away from Sonos’ core functionality.  You may not have the need to be “constantly adding it and removing it from groups”, but other users (including myself) do.  In fact, this functionality is the reason Sonos exists, otherwise they are merely a single speaker company with no multi-room function at all.  Which is why we tell people who want a single speaker to connect to a computer to buy a single speaker which is made to connect to a computer (mislabeled marketing blurbs from Sonos aside).  

Hello

i am interested in buying the Era300. I still many CD’s and i also have laptop-stored mp3’s. I like the feature that the Era 300 can be connected to computer and Hifi systems. Would anyone help me to understand which port i would have to use on my external drives, please? on the marantz is it the aux out port? and on the computer? just my microphone port (it’s an older computer so no bluetooth possible)?

thank you so much all

Roberto

Aux out would be possible, yes. On the computer "microphone” seems an “in” to me, not an “out”. Not sure if a speaker connection would work. Sonos can reach out to your computer however, to play the music stored on it, se https://support.sonos.com/en/article/add-your-music-library-to-sonos (max 65k songs) or use Plex.

Will you also be playing speakers attached to the Marantz?

No i want to get rid of my focal lab speakers and connect only the sonos