I have a 20 year old receiver with no LFE out. Can I hook up a sub to it?


I am guessing that I connect the receiver's speaker outputs to the subs' speaker inputs, then run the sub's speaker outputs to my L/R front speakers (M3Ti's).

Is my receiver now driving all three speakers? Is the sub's amplifier driving all three speakers?

Are there risks to this approach? How do I set the cross-over, phase, and volume?

If the sub is powered, this will work. The receiver will not be powering the sub; it will simply be delivering a signal to it. The sub's internal crossover will then separate the signal - the sub will handle the low frequencies and pass on the higher frequencies to the M3's. Some people feel this results in better sound from the bookshelves since they don't have to try to produce the low frequencies that the sub handles. An alternative is to run separate speaker wire from the receiver outputs to both the speakers and the sub - then the M3's will still run full-range. Try them both and see what works better for you.
If your sub isn't powered, you'll need to get a separate amp for it. The receiver won't have enough power to run both the M3's and a power-hungry subwoofer.

Good Luck.