How many RCA's

[zachzinda]

I have three RCA pre outs on my Alpine head unit. How many cable/splitters do I need to connect to a HT-4,HT-6 to power four xs-65's, 10-fa and two Rev-10's. Im still on the fence about ordering the ws-420 or Kicker zone control so would this change what RCA's I need.

[chpthril]

I have three RCA pre outs on my Alpine head unit. How many cable/splitters do I need to connect to a HT-4,HT-6 to power four xs-65's, 10-fa and two Rev-10's.

You will need one pair for the HT-4 powering the Rev-10
You can run the 4 in-boats and sub with only a single pair going to the HT-6. I would do this for now until you add a zone controller. This will have the sub volume tied to the in-boat volume. You can run a dedicated set to the HT-6 for the sub and use the Alpine's sub level control, but its kind of cumbersome to do on the fly.

Im still on the fence about ordering the ws-420 or Kicker zone control so would this change what RCA's I need

Yes, it will change the length and quantity.
The WS-420 will require 4 pairs: source unit to 420, 420 in-boat zone to amp, 420 tower zone to amp and 420 sub zone to amp. All long enough the to reach from the head-unit to the 420 and back to amp wall. Something like the WS-420 cable kit.

The ZXM-RLC will require only short RCA cables as it uses a data cable from the helm mounted control knobs to the module which can be mounted at the amps. You will need at least 3 cables. source unit to ZXM module, module to in-boat/sub amp and module to tower amp. The longest one is typically the RCA from the source unit to the module.