What will your music source be? If the Fives are “dedicated to music only” why connect to the tv? 
 

Sonos provides speakers capable of working in a wireless, multi-room environment whilst proving synchronised playback in those rooms. To achieve this a small (approx 70msec) delay is introduced when streaming starts. For music this doesn’t matter, but for video it does - lip sync is the typical issue as sound and vision are out-of-time. With a Sonos Playbar the delay is reduced for tv sound to the Playbar so lip sync is not an issue. 
 

If you want to “listen” to dj sets on YouTube through the Fives, this will prob be an issue. But you have your Samsung soundbar connected to your tv, so why get the Fives? 

The 3.5mm “Line-In” jack is stereo. The two FIVE’s could be “Bonded” to operate as a stereo pair. In SONOS lingo this Bonded pair becomes a “Room”. Any Line-In can be played in any combination of Rooms. You could connect the TV to one FIVE and a phono to the other FIVE.

Because of the time latency between Line-In and output from a speaker, I discourage using SONOS as a DJ system.

My music source will be Spotify (no issue for that I guess) but It will also be YouTube on TV to play video clips.

I don’t want to use the Samsung because I dont like the sound it provides for stereo music so that’s why I was hoping to have 2 separate systems to get the best audio quality for both environment (movies & cinema)

Buying a Sonos amp couldn’t resolve the lip sync issue ? Is it possible to pair 2 fives on it and the tv as well ?

I use Sonos in my system for TV and find absolutely no issues of any sync as long as the delay is set to minimum via the Sonos app.

But as recently posted elsewhere, this may be a benefit to me of something happening in my TV, and I don't use the set up for anything other than passive watching of TV including YouTube videos.

If you can get the Sonos units on returnable basis, do so and see what happens. If there is an issue you will realise it immediately and do the return.

Correct about Spotify - no issues there.

I would assume the 3.5mm Jack on the tv is a stereo connection. That will go into one of the Five’s which will separate the Left and Right signals and play out to the appropriate Five provided you’ve set them up as a stereo pair.
Sonos does offer a trial period, so buy ‘em and try ‘em and see whether the sync is an issue for you. 

Are you using Sonos Fives ?

Ok thanks for your messages, I think I will give it a try and return if not working.

So If I understand I l’ll have to plug one five to the tv with jack 3.5 and the other one is connected wireless to the other ?

is there also an equalizer on the app I can ajust for Highs, medium etc.. ?

Yes, the 3.5 has to be a stereo cable connected to the left speaker and the speakers have to be wirelessly connected as a stereo pair using the Sonos app.

Yes there is an equaliser to adjust bass/treble.

I am using a TV to Sonos Connect to Yamaha amp to two speakers. In effect the same as a Sonos Five because the line in jacks on all Sonos units work the same way.

Ok thanks and last question:

Will I be able to adjust the volume from my TV remote control ? I guess I won’t as it’s not ARC ?

That will depend on the nature of the tv output. You’ll know when you make the connections and try it. I would expect it to be a variable output. If not, the app gives volume control. 

Probably a headphone jack and therefore variable via the TV remote control. Or of Firestick, if that is the source.

Ok thanks for the answer.

I listen mainly electronic music with heavy bass so I want to add a subwoofer to my pair of Sonos Five to make a 2.1 system but do you think putting 2 subs side by side is an issue ?

Here is my living room and the setup I would like to do :

(The Sonos Fives will be elevated on support on each side of the TV)

You can only use dual Sonos Subs when they are connected to a soundbar, with just a pair of Sonos Fives, you’re restricted to a single Sub. I’d try it, hard to imagine it wouldn’t be enough. 

I know, it’s just that like I said I have 2 separate systems.

 - The Samsung one for movies

 - The Sonos One for music

When i’ll listen to music the Samsung sub won’t be working but I just wanted to know if in term of placement it’s not a problem

Your ears will be the best determinant as to locational positioning. 

To throw another opinion out there, trying to use the Fives for TV audio, while it may work in a satisfactory manor, is just not the best solution for your situation.  Why not just get a Sonos amp, which is designed to connect to your TV, and use to to power some good quality passive speakers?  You will avoid having the delay you would get with Fives.  You can add a Sonos sub (or 2) or any third party sub (maybe your existing Samsung sub).  You can probably replace your samsung soundbar for movie watching and add rear surround speakers if you wish.

Also, I know you said you don’t want a soundbar, but your room is not that deep and your planned stereo separation isn’t that wide.  The Arc does a pretty wide itself, and you may find that if you’re only going to separate your speakers by 120 cm or so, an Arc simplifies things and gives you a lot more features.

Full disclosure, I don’t personally use the Arc for music, because the space it’s in is open concept and about 20 feet deep and 20 feet wide.  I use the Arc for TV...well, and atmos music.  I have a pair of Fives for music, but they are never used for TV, and about 10 feet apart.  In another, I use a Beam for both TV and music with surrounds ‘helping out’ for music.  I’m not really trying to create a sound stage in this room though.

Interesting opinion, yes I know the Arc is a good soundbar but I really don’t want to replace my Samsung or add a new one!

Regarding the Sonos AMP yes you’re right, it’s a solution I was looking for but it’s pretty expensive 

Maybe I could save some moneys buying a pair of Sonos ERA 100 instead of Fives and get the AMP (it would be the same cost)

Are the Sonos ERA 100 as good as the Fives ? 

Also, as both speakers (ERA 100 & Fives) are bluetooth compatible, wouldn’t it be possible to connect the TV through bluetooth to get rid of this sync delay issue ?

ERA 300 would be a better comparison with FIVE.

FIVE is not Bluetooth compatible. Here is the list. Be sure to read the details for each model.

Regardless of how you connect, there will always be a latency. Lip sync will be best when using a soundbar.

If you get Era 100s or Fives, there is really no benefit to get the Sonos amp.

That’s not the right question.  Better question is will the Era 100 fill out the space I intend to use it in?  Probably so, giving room for personal preference.  The Fives will definitely fill the space and may very well feel like overkill.

Repeating what’s already stated, the Five does not have bluetooth.  You might reduce the delay a bit with bluetooth with the Era 100 or Era 300, but you are still using the speakers in a way that they are not designed to be used. I do use Era 300s connected via bluetooth to a TV, but it’s because I rarely use the TV and am not looking for great sound quality in that scenario.  If I was using the TV to play music, I would use a Sonos speaker designed to connect to work with the TV.

I think Sonos themselves say that for pure stereo listening, the Five pair is the best option. The Eras only come ito play if you want spatial audio. The Five could have a Bluetooth receiver plugged into the aux input.