Question Receiver LFE out / Subwoofer RCA in. How?

[deanspeed]

I've taken my expensive sub and amp out of my truck before I traded it in (Dealership didn't care about it), and it wont fit in my current vehicle. For the time being I would like to use it in my living room. My living room receiver has the typical pre out LFE for subwoofer and my mono amp which came out of the truck has the RCA L+R in. Through my google searches, it seems as though the only difference is that LFE includes the same signal but combines L+R. So does this mean I can technically plug that single RCA cable from receiver into L or R in on the mono amp and be fine?

Trough testing I found that if I go from a headphone jack from several devices I tested and I set the crossover and gain correctly on the mono amp then it sounds really good. But going from the pre out on my receiver just gives me a loud hum. Makes me think LFE is a digital signal (which is what I originally thought before google research) and that I might need something to convert it to a analog signal. Can anyone shed any light on this?

Just looking for more info on my specific situation, and any suggestions as to why I'm not getting anything from my LFE out to my RCA L+R in.

Edit:
Alternatively I was thinking of connecting extra speaker wire to the front left and right channels and splice in RCA connecters at the other end and send that to the mono amp for sub, and disable sub in the receiver so that all bass goes through the front left and right, and control the crossover from the mono amp. I'm thinking this might be a better solution, unless it will affect the quality coming from the speakers? I haven't tried this yet as I just thought of it. I'll wait for a response before I try it. Don't want to break anything.

Edit 2:
Does L and R channels carry the same bass signal? or is it dependent on the audio being sent to it? If the same bass signal is going to L and R speakers, then technically I can just go from the speaker closest to the sub, rather than both speakers right? Either way I have plenty of speaker wire, sooo...

 

[deanspeed]

I Just wanted to give an update for anyone else who might be interested in this. It turns out that my mono amp accepts both low and high speaker level input within the thresholds of what my home theater receiver puts out. I am running two speaker wires from my front left and right channels, one going to the speakers and the other going to my mono amp. On the mono amp side I have added RCA connections onto the speaker wire so that I can plug it into the amp. As I understand, this is how car amps are designed to receive a signal, so while it seems I am jerry rigging, this is actually the proper way to do this. If I remember correctly, this is pretty much how it was installed in the truck. I also realized I didn't mention what devices I am using, so I will list them below. Also this should work universally so if you have similar equipment this should work for you as well. The only issue I seem to have is that I have the gain set all the way down and the bass is still pretty loud. This is only a problem when listing to music late at night as i'm worried about my neighbors even though I live in a house as I can easily hear the bass from the street when I have the volume at mid levels. I'm thinking this could probably be fixed if I had the Wired Bass Boost Remote that goes with the amp, which I don't have. If not that, maybe a potentiometer spliced into the speaker wire going to the amp to control the voltage of the incoming signal? If anyone has any ideas on how I can solve this problem please let me know, for now I just turn off the power supply to the amp when listing to music at night so that my neighbors won't hate me... as much.

Receiver: Yamaha RX-V677
Mono AMP: Pioneer GM-D9601
2x Subs : TS-A3000LS4
Power Supply for AMP: ATX Power supply from old pc.
Enclosure: Dual Sealed / Wedge Shaped Truck Subwoofer Enclosure