Front outs run to my 4 channel amp so my front components get the same signal as my rear coax and I use my sub outs for my mono/sub amp.

 

I would skip the band-aids all together and invest in a new deck with tripple pre-outs.

If you are in a position to add more power for better performance, why not begin with a cleaner/better equipped source ?

Decks are cheap these days. You could easilly pick up something brand new for just over $100 that would most likely have a possitive effect on the entire signal chain and still give you room to grow in the future.

 

I know i could get another HU for not much with 2preouts but i just got this sony(whatever it is) for free and really not a long time ago.Since its almost new i wanted to keep it but since it doesnt suit up my needs pretty good. imma see if i could sell that thing and buy a new one.

 

you could always just buy a 3 way crossover that will split one rca wire into three so you can have an rca for the sub one for the fronts and one for the rears because you are running a four channel you will need rca wires for the fronts and rears

 

If my 4 channel has one input and one output Can i use it? can i hook up my sub's amp on the output of the 4chan? I still never owned a 4chan so i really dont know whats that all about input/output thing.
is the signal going to be for 2 sub's amp?even though the first is for speakers
Thx for all the answers so far i thought my post would have disapeard fast!