I'm not sure how old your FM/AM/DVD component is, the ability to do surround sound is tech built into the "playing" equipment - rather than the speakers.
However, with any "semi-recent" 5.1 enabled component (pretty much everything since the mid-90's or so) you should be able to hook up all your RV speakers for surround sound - presuming they're positioned for an at least decent surround field/experience anyway. This is a general 5.1 layout:
It doesn't have to be exactly right to get a good audio performance, like you can put surround right and surround left speakers directly on the sides of the seating area and it'll sound alright.
If you have a "down firing" subwoofer (aka the speaker is actually facing the floor and there's no speaker on the face of the sub) you can put it anywhere in the room, closer to the seating area is better.
If you do get a new AV receiver, you would just plug the closest corresponding speaker position's wires into the AVR speaker terminals as named above and you should be good to go.
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What do all these numbers mean!?! 2.1, 5.1, 7.1, 5.2.2, 7.2.4, 13.2.6, etc.
It's way easier than you think! Just break it down
13 = 13 satellite/typical speakers .
2 = 2 subwoofers .
6 height or presence speakers.
All the current formats of film/cd/dvd/tv broadcast/pc/etc. dedicate individual audio "tracks" to individual "channels" on the receiver end, which the receiver feeds out to the different speaker locations.
Every format will have a dedicated front right and front left audio track, nearly all also have a dedicated channel for the LFE or Subwoofer. At 3.1 you add in a center channel. When you get up to 5.1 it adds a right surround, and a left surround. At 7.1 you add in right and left rear surround channels.
Everything past 7.1 is wizardry inside your receiver because most film/cd/dvd/tv/etc doesn't record audio tracks higher than 7.1 - in fact, you can't even fit the necessary data to run higher than 7.1 on the cd/dvd or TV broadcast coax. Bluray and fiber cable could do more, but Hollywood and music producers aren't onboard with maor speakers yet. However, the wizardry in receivers can be pretty amazing.
Still worth bearing in mind that the best you're only ever going to get from any receiver is 7.1 - front right, front left, center, surround right, surround left, rear surround right, rear surround left, and a subwoofer. Everything else your receiver bills to you is [currently] just a copy of those individually recorded audio tracks - sometimes with the receiver fiddling with the tracks to try to "simulate" having more tracks, but it's kinda smoke and mirrors.
Also be aware that receiver companies sometimes include 2 "channels" in their labeling which are actually hardwired to a different zone. So they'll label that it's a 9.1 system, but it's actually 7.1 with 2.0 in Zone 2, and those two channels for Zone 2 are basically a straight up copy of the front right & left audio tracks, which means they aren't even suited to use as duplicate [side] surround channels. Making them essentially a waste of money if you're not going to have a zone 2.
Here have a wall-of-text history; because I love this stuff heh
When they recorded movies between the late 50s or so and the early 70's, they started including duplicate tracks of the audio via magnetic tracks on the edges of the projector film mostly in order to bring the audio to every seat in the theater because originally they just had three speakers behind the screen and folks in the back often complained of not being able to hear it or whatever.
As the tech advanced, the equipment (projector, receiver, whatever else odd components they had back then,) through a process called "sound panning" would automatically adjust the individual volume of those tracks as they were sent to the side mounted speakers; simulating the effect of objects in the movie going past the viewers. I believe Disney's Fantasia was one of the first movies to fully utilize the multiple audio tracks for this purpose. However, this early ancestor only had a single audio track that went to all of the side and rear mounted speakers in the room. The equipment that did the sound panning had to be custom built and designed for the specific theater's room and so forth (and that's when we started getting a standardized size for movie theaters.)
It was in the 70s that we started to get close to "modern" surround sound as we know it. Dolby came out with a multi-channel audio format that included audio tracks for the individual speakers on the sides & rear of the theater. Star Wars was the first movie recorded in this new Dolby Surround and it was the first time that movie producers were able to add in audio tracks that were specifically designed to utilize the physical locations of the speakers in the theater with separate audio tracks. Instead of adjusting speaker volume's onsite via customized and expensive sound panning, they built the side speakers volume adjustments into the actual film itself. This meant they were no longer required to custom build the surround sound system to fit the theater, they just had to properly position the speakers to conform with the Dolby multi channel format.
In the early 80s "Dolby Sound" was released for home entertainment systems - which had channels for right, left, rear speakers, plus a subwoofer. As our data storage and carrying technology increased, so did the audio track data Dolby could stuff into the slot available to them on the film roll, or contained in our home movies (*cough VHS *cough* and even the data carried in over-the-air TV broadcasting.) In the late 80's came Pro Logic for home entertainment - this added a front center channel to the mix. But there was a bit of a hard cap on how much they could fit on the film tape.
In the 90s came digital surround sound format "DTS" by a company called Digital Theater Systems - this is true modern surround sound. IIRC the first movie to use the new DTS format was Jurassic Park. DTS has 6 separate audio channels; front right, front left, front center, surround right, surround left, and a subwoofer.
Dolby countered with "Dolby Digital" aka "Dolby 5.1" aka "Dolby AC-3" aka "Dolby SR-D" (they couldn't really settle on a name) - while this had the exact same audio channels as DTS, Dolby encoded those audio tracks as tiny patterns on the film in the spaces between the sprocket holes - basically doubling their film real estate. Later came "Dolby Digital Surround EX" which added in a single channel for any rear speakers.
The most recent entry was Sony Dynamic Digital Sound (SDDS) which has better error correction then "Dolby Digital". SDDS brought the possibility of 7.1 audio.
Now we've hit the same kinda data bottle neck of the 50s, you can't get 7.1 audio through conventional cable TV. However it is the current standard for DVD formatting. 7.1 gives you front right, front left, center, surround right, surround left, rear surround right, rear surround left, and a subwoofer.
Blu-rays atm are doing 7.1 as well, while I do suspect they could easily do more than even 13.2.9, I think the consumer desire for that much audio swag is relegated to us fringes of society known as audiophiles. We have a ton of money to buy all the toys, but, it's still not enough to prompt Hollywood to give us moar stuff.
Dolby came out with ATMOS which is an actual "speaker based" tech to fire sound upward and bounce it off the ceiling (gives you height/presence speakers without having to drill holes in the ceiling.) ATMOS does.. or did, have the capability to send audio to each of the surround right and surround left speakers separately, and with the up firing ATMOS enabled speakers, it could really pinpoint a sound to a specific location in the theater/home, however again Hollywood and Music producers were not on board. I hear Dolby is shuttering ATMOS now; making me a rather sad audio-fox since I just wired up my office/home theater for 15.2.4/13.2.6 surround :/
