I'm replacing the receiver/DVD player from a Boston/Kenwood package
with a regular TV receiver. The powered sub connects to the main unit
via a shielded cable with some sort of DIN (?) connector that has three
pins. I'm presuming that the pins are signal +/- and a control pin to
turn on the amp.

What's the possibility that I could drive the sub with the subwoofer
pre-amp out from the new receiver? I'm presuming that since it is an
amplified sub, the input impedance is going to be relatively high, but
how can I check it. I have an oscilloscope so I could check levels if
that would help. What output voltages would I typically see on pre-amp
outputs?

Any other pitfalls?

thanks,
hank