Stereo questions...

I gave up on cd’s since i can carry my entire music collection in my phone. I picked up a bluetooth receiver that plugs into my aux input on my deck.

Not what you want to hear,i know. You need to get a little newer deck that at least will play a cd. And aux input.then you can add a cd changer.

Exactly what I was thinking.
Pretty much everything is on my phone now, and I have wireless transfer to my phone from my computers or tablet.
Awhile back I got a nice little Pioneer unit from Wally World for right at 100 bucks for the Wife's car.
4 channel, balance/fade, Blue tooth, USB, and CD/CDR/CDRW/MP3 disc player.
WAY more functions that she will ever use, but some really convenient ones that she will. (Like caller ID on the stereo face and the ability to use it as a hands free phone on the move)

I watched a review on a Sub unit for around 50 bucks that has the amp built into the box from WW also.
Power the box and connect speaker wires to it, and it filters everything but the bass out of the channel to the sub without messing with the original 4 channel output from the stereo.
The guy said it was a good unit for the average person that wanted a sub to supplement a system and well worth the 50 bucks.

I can't imagine fighting an old unit these days when amps are so inexpensive and plentiful.
(Phone, amp, speakers is all thats really needed when it comes right down to it.)
And there are so many online radio stations it's ridiculous.