Would it be possible to add these to a receiver that doesn't already have them? They'd be sending a signal to a Paradigm control unit and then to a BFD.
Maybe, if you are willing to cut traces and solder wires/connectors onto your receiver's circuit board. Provided you can find exactly the right connections to tap, that is. It's possible, but for me at least it would take some courage to modify a perfectly fine receiver this way. What is the purpose of having preouts and main-ins for you?
My receiver only has a mono sub output, meaning it sums the 2 channels into 1. I wanted to do a stereo sub setup, but since I'd have to mess with a good receiver, probably damageing it, I can do it another way.
As has been stated above, this is possible, but may be difficult to implement depending on your knowledge of electronics.
First, does your integrated amp have a separate power amp and pre-amp board? If so, then you can tap into the connecting wires to do the pre-out/main-in. Otherwise, you'll have to trace the PCB and either cut a trace, or remove components to effectively do the same thing.
Next we need to make sure that you are not loading the preamp stage too much, or the power amp stage, so you need to either have knowledge of the output and input impedance of the place where you are tapping in to, or you can buffer them with an opamp buffer. You may also need input and output caps.
I would suggest that this is not something to be taken lightly.
Another possible option is if you have a tape loop with monitoring capability. ie. Can you set your amp up to an input, and press another button to hear what is happening on the tape in's, without altering what is going out of the tape-outs?
If you can, then you may be able to set up the tape-ins and outs as your pre-out/main ins.
The main problem with this will be volume control. You'll have to do the volume control on the active xover, and leave the main amps volume set to max.
Jonathan (yes it is a great name) my receiver doesn't have a tape monitor. And it does have a seperate poweramp and pre amp board, but my knowledge of electronics isn't that great, so, at this time, it isn't a good idea. Thanks for the help nonetheless guys!