alternative to a line level input. Unfortunately, the Monitor Audio Bronze BXW-10 does not have speaker level inputs. I'm out the door right now, let me think about it and I'll get back to you unless someone else addresses it adequately.

Does your amplifier have pre out power in connectors?

Does your sub woofer have a pair of line level inputs?

If the answer to both questions is yes, connect the sub woofer between the pre out and power in connectors. Adjust the crossover frequency and level and you're good to go.

For most sub woofers the line level high pass signal is a pass through with no filtering. So your mains will be running full range.

Most sub woofers have high and low pass filters on the speaker level connections. Unfortunately on most sub woofers the crossover frequency is around 120Hz. This is much to high for most decent speakers and can lead to being able to easily localize the sub woofers position. This is undesirable.

Try both ways and come to your own conclusion.

It is a competent piece which should sound great with the MA speakers. Good luck!