Is your plan to use the Era speakers as surround speakers for the Arc? If so, I’d consider doubling the Fives for playing back the CD player….but honestly, I’d rip the CD’s to my PC, and just play the music using the Sonos software. I’ve always not been interested in listening to all of the songs on a CD, and the ability to build my own ‘playlist’ is overly compelling. But I’d still get the pair of Sonos Fives to listen to music…in fact, I have. They flank my Sonos Arc. The Arc is for movies, the Fives are for music. 

How many CD's do you own? The standard Sonos database can handle 65.000 entries. If you have losts of music Plex or iBroadcast would be an option.

I was thinking of using the era 300s as rear speakers and the Arc Soundbar as the front speaker.  I do like your idea of having two Fives for music and connecting the CD Player. 
 

Sony Bravia TV and Arc Soundbar set up TV/Movies.

Sonos Speakers:  2 Fives + CD connection

Does that sound right to you?

in 2000, I set up a home theater Paradigm System:  Two standing speakers, a central speaker, a subwoofer, and receiver plus CD player. I’m in the process of downsizing, so your suggestion is ideal.  
 

Thanks

Veronica

PS.  Will this be easy for me to set up?
 

Hi @VFJazzJunkie 

Welcome to the community!

Your idea as below is great. I have a similar setup

• Sony Bravia TV and Arc Soundbar set up TV/Movies.
• Sonos Speakers:  2 Fives + CD connection

If planning to use Era 300 as surrounds (rear speakers) know that they will no longer function independently. They will be bonded to the Arc and subject to whatever audio is sent to them by the Arc. If playing Music through the Arc you can set the Era 300’s to play in full stereo and auto-switch back to surround mode for movies.

As you will have Fives in the same room for your CD player there may be a temptation to group them with the Arc when watching a movie. DON’T DO IT. Doing so will introduce a 75ms delay to the Fives creating an echo effect.

Cheers!

Edit: Setup is pretty straight forward….

• Start with the Arc and add Era 300 as surrounds. 
• In the Sonos app setup each Five as separate room (for example CD 1 and CD 2)
• Select Five CD 1 > Create Stereo pair > The app will guide you through the process.
• Connect the CD Player  (RCA-Out) to “left” Five (Line-In) of the stereo pair using a cable like this

I listen to some music on my Arc as it has a Sub attached which is great for some of my music. Still the stereo imaging is less than I’d like to have but plenty good enough compared the the cost of adding a pair of Fives just for music there. If I listened there more often I’d sure get the pair of Fives.

I ripped my CD collection to a lossless format many years ago and haven’t had a CD out of the case in about as long. It is just so much less hassle to click a couple times and play from my music library than to dug out the CD, load it and select the CD player as a source. Playing a multi-CD set is even more convenient even though I could fit the first five in my old changer.

Try the Arc for music, try both modes for the surrounds and then if it is worth it to you grab a pair of Fives.

I have just set up the SONOS system with the ARC as the main speaker directly below a 75” TV, 2 x era300 (just arrived last night) at the rear end walls (orange) and a Sub Gen 3 placed near a wall behind the sofa in the middle of the room (illustration below isn’t accurate as I have now placed the Sub Gen3 at the opposite side of the T-shape structural column. So far, i am enjoying the experience playing music even before doing any Trueplay tuning. 

As a newbie to SONOS products, setting up was a breeze, just follow instructions via SONOS app and it’s done within minutes.