Amp/Sub wiring question

I am installing a Rockville RA10CA slim subwoofer.

If I connect through the high frequency inputs using the rear speakers do I need to connect both L and R rear speakers or can I use just one?

Also, If I were to connect using the PAC SNI-35 Variable LOC Line Out Converter with the RCA cables would this improve the performance or is it basically the same since my Uconnect 5.0 does not have built in RCA?

Thanks!

Speaker level inputs are better than rca's especially if you have to use a line output converter. And for a subwoofer you really only need 1 channel. I always use 2, but it's usually not completely necessary.

What's your opinion of the Rockville?

I was going to buy the RMW8A 8" 800w Powered Sub to put underneath my back seat, because I don't want a lot of bass & it's only $81, but I noticed Rockville products seem to get a lot of bad reviews & feedback on ebay.

Thanks Justin, I hooked up the L speaker level input and seems to be working great. I ran the R wiring while the seat was out just in case though did not hook it up.

Stevon, in regards to Rockville I have seen mostly positive reviews and comments and for the price it works for me. Disclaimer is I have never been an over the top audio guy, I usually change out stock speakers and a head unit here or there (all kickers this time). I liked what I heard tonight. I set my head unit bass at mid and sub level at 3 of 10 and it was more than enough for me. I placed it behind my rear seat. That Ebay price on the RMW8A looks tough to beat. I am thinking I should have gone that route now, lol. Time will tell on how durable the sub is, fit and finish on this sub was very good.