So your Edifiers have an optical input, so I would get a toslink optical cable and connect that to your optical out on the SBZ (going to get the cleanest signal for sure). The Edifiers also have a sub output so that's probably the best bet as well.
Not sure where you're getting the Jamo, and nothing against it however in my area there is the
Acoustic Audio PSW-15 which seems to be a much better deal for a bit less money.
EDIT - so after reading
this review on those edifiers, perhaps the sub out is not ideal and maybe the line-out from the SBZ is a better way to connect it. On a positive note, an optical cable is included, so you should be all set up for some excellent sound quality from them.
EDIT2:
ok so I think the best way would be to use the SBZ's analog line out to both the speakers and the sub. So the first thing you need to get would be the 1/8" jack to RCA adapter:
iXCC Premium Gold-Plated 3.5mm Male to 2 RCA Female Stereo Audio Y Adapter Extension Cable (1ft)
which are shielded and will give you a good signal, you only need one of these. So we need to split both of those connectors so we can connect both the speakers and the sub:
Mediabridge ULTRA Series RCA Y-Adapter (12 Inches) - 1-Male to 2-Female for Digital Audio or Subwoofer - (Part# CYA-1M2F-P)
As the name implies, it's also use to connect a single LFE out to subs that have 2 L/R inputs like the Jamo - it is also shielded so it's still a good signal, you need to get 2x of these - one for each RCA connector on the previous cable. Once you connect both you will now have 2x left and 2x right RCA jacks.
Now we need to connect them to the speakers and the sub:
AmazonBasics 2-Male to 2-Male RCA Audio Cable
Get 2x of these, one will go to the speakers and one to the sub.
so to connect it up will be something like this:
[SBZ] "line out 1 / Front L/R" 3.5mm to RCA L -> RCA splitter -> SPK L
________________________________________RCA splitter -> SUB L
[SBZ] "line out 1 / Front L/R" 3.5mm to RCA R -> RCA splitter -> SPK R
________________________________________RCA splitter -> SUB R
EDIT3:
Just realized there will be an easier way once I found the right cable... This will be a bit easier since you can ditch the Y adapter above so less connections is better.
Still need the 1/8" jack to RCA adapter:
iXCC Premium Gold-Plated 3.5mm Male to 2 RCA Female Stereo Audio Y Adapter Extension Cable (1ft)
which are shielded and will give you a good signal, you only need one of these. Now connect them to the speakers and the sub:
AmazonBasics 1-Male to 2-Male RCA Audio Cable
Get 2x of these, one will go to the speakers and one to the sub. Also shielded for good signal - so to connect it up will be something like this:
[SBZ] "line out 1 / Front L/R" 3.5mm to RCA L -> RCA SPK L
________________________________________RCA SUB L
[SBZ] "line out 1 / Front L/R" 3.5mm to RCA R -> RCA SPK R
________________________________________RCA SUB R