Hi everyone! I could use some advice on hooking up my HK-PA2100 amp to drive two 10" subs that built into my 2 front/main speakers (custom built speakers) each speaker has separate terminals one for the main/front speaker and one for the sub - note that you can run as single speaker wire to feed both, currently that's the way it's configured, I would like to drive the subs independent from the mains with my HK amp. The problem is my Onkyo HT-S580 has no preamp output, it does have ONE line level output to be used with a cheap onyko passive sub that came with the receiver. The onkyo does have spring clip terminals outputs for both "A and B" main speakers outs however per the owners manual " when speaker B is turned on, speaker A is reduced to 2.1 channel. Note that my hk amp only excepts one RCA input, that's it. In my research I have found info about Line Level Audio Connectors & Adaptors they would convert my receivers single sub line out to an RCA out. Would this work or does anyone have suggestions for my application?
Use the subwoofer out on your onkyo to the amp. This is a pre-out, it doesn't matter that it drove smaller sub before. It is just feeding the base notes to the amp which will do all the work.
Do NOT use the sub out from the onkyo to the Hk. The sub out is powered, and the HK is looking for line level inputs. from here, your best option is probably to get 2 plate amps from partsexpress (or equivelent) and mount them on the front speakers. Then run the sub out to each plate amp at speaker level inputs.
