Beginning Sonos user

The 5 and the Boost ought to be enough to start - unless you want to hear apps based music from the wired speakers as well. Or if you will want to hear the CDs through both the 5 and the wired speakers at the same time. For using the wired speakers, you will need the Connect as well.

Here is the thing though - the Connect isn't cheap and if the wired speakers are not part of beloved hifi kit, for just a little more you could get a couple of play 1 units, and do away with the wired speakers, their wires and the amp. Or, if music in two places is not required, get another 5 unit instead of the Connect and dispose of the wired speakers in the same way.

Play the 5 units then as a stereo pair in place of the wired speakers, supplying music to them from the CD player as well as from the internet. In time, he may well want to do what most that have a large CD collection do - rip and transfer all the CD content to a NAS, and get rid of the CD changer. That way, if one has 1000 CDs, effectively one gets a 1000 CD changer. Or whatever larger number of CDs one has. That, allied to what is available from the apps, is a best of both worlds solution, but you can get there in phases.

In the above plan, I recommend starting with just the Boost and the 5 unit and see how things go, if the wired speakers, in principle, qualify for the "to be disposed" list.

I agree with what Kumar stated. But also, I would add/ask is where the Play:5 will be situated relative to the router and how strong is your home network. You very well may not need the Boost at all.

1st, Sonos Play speakers can be, but don't have to be, wired to the router. By wiring even 1 speaker, you create a stronger and more stable network called SonosNet. This is essentially what the Boost does, without the added $100 the Boost costs.

2nd, instead of the Boost, you might want to consider putting a Play:1 near the router and wiring that component. Again, you'd get the benefit of the Boost, but you'd also get the benefit of another speaker in your system, for not a whole lot more cost.

3rd, before buying other equipment like a Connect, I would establish how your Sonos speaker(s) will be used. As Kumar mentioned, adding a legacy system to the Sonos ecosystem can be done, but it may not be the best use of money considering the availability of the newer technologies.

TL/DR: I would focus on the Play speaker(s) 1st, then the Boost and/or Connect if needed/wanted.

Thank you both so much!! I have a tendency to "over-do". When I purchased the Play 5, I also bought a Play 1....No idea why, just seemed like a good idea so now All I need is 1 more ;)
All components (at least for now) would be in the same room, and is very easy to put any piece next to the router. This is all so new to me I don't even know what all this system can do or what I can put where or what is needed to do it. I'm sure I'll be surprised.
How do I know if the Wi-Fi connection is strong enough for him to use with the Sonos, while I'm using it at the same time? I want him to LOVE this and want to avoid any hiccups that may cause him to feel otherwise.
I really appreciate all the advice. It helps a lot!!

He will love it (if he can deal with change, as Sonos is definitely a change in how to access music).

I am betting that if you plug 1 of the speakers (either one) into your router, you will be 100% fine with just the speakers and no Boost.

Per my cell phone settings it shows 72mbps link speed, and 2.4 GHz frequency in the room the Sonos will be. Will that be sufficient without the Boost?

If you can wire any of the play units to the router, the Boost is NOT needed. Don't worry about what your cell phone tells you, if the router and the play units are in the same room, all should be good

Wiring one unit to the router sets up a parallel network dedicated to Sonos, and addresses your question - yes, both of you can use the router at the same time.

I don't know your equipment, so hard to tell. That 72 might be a reflection of your phone's max speed.

Anyhow, I do think that by plugging in 1 of the Sonos devices you will overcome any wireless issues. And if not, upgrading your router would yield additional benefits to your overall network anyhow (IF and only if that is needed, which is unlikely).

Thanks, you've both been a huge help! Merry Christmas to you both !!

Same to you

Imho, to get "window shaking levels" you'd need not just one Play 5, but a couple of Play 5 and a Sub. THAT would really shake even your house foundations, if your hubby is used to jet engine noise levels. Out of the joke, Play 5 are famous for their elegant sound, and they will never scream like banshees. A second Play 5 adds the chance to use them as a stereo pair, widening the sound stage and maxing the overall volume. A sub will add depth and punch, giving you a sound very close to old hifi systems, and in my opinion way better.
One of the stunning things with Sonos is the multi room sound you can get. You could place the 5 in a room, a 1 in the kitchen and another 1 in your bedroom. Then syncing them will make your whole house sound together, letting you sing along your fav tunes without the need to keep wandering in the same room waiting for your song to end before moving. It's a magical experience, you can't guess how it is before you try it yourself.
If you put your 5 near the router, directly wired, you wont need the boost. You'll need the Connect only if you want to keep the old hifi set, and let it make its slice of noise along with the Sonos system. Or you want to play something on the Hifi set and let the other Sonos items play along as well.
Hope this helps
Merry xmas!