Tips on how to get the best value with your home entertainment music system

Manuals (randomly chose a Series 2 from 1990-1994 - if not that, then choose the series from the Bose site)
https://www.bose.ca/en_ca/support/products/2_speaker_home_theater_support/am3_series2.html

https://www.bose.ca/en_ca/support/search.html?category=2_speaker_home_theater_support&query=acoustimass+3&queryForDisplay=Acoustimass+3

There are a number of different models. Assuming you don't have a Powered version of the speakers (You'll know you do if you have to plug the subwoofer into AC power)
For the Unpowered systems, the subwoofer plugs into the Speaker R and L outputs of a receiver or an amplifier, so you will have to provide amplification. The satellites plug into the subwoofer and are NOT intended for direct connection to an amplifier.

You should be able to use whatever amplifier has audio inputs from your TV, and regular speaker wire connections out.

In any 'connection' question there are at least two participants and specific answers require specific details. WHAT monitors?

The manual for the known part of this scenario is here.

http://www.retrevo.com/support/Behringer-UB2442FX-Pro-manual/id/23281bh544/t/2/

Since it's not an amplifier you will need one before you can consider connecting speakers.

You should follow the manuals for the unknown parts, too.

Did you remember to remove the shorting link on the MA BR5 speaker terminal ..When you biwire the speakers you should remember to loosen the speaker terminal nuts and remove the shorting link plate between the HF and the LF terminals or you will short the amplifiers two channels together through the link. And modern amplifiers will take a lot of abuse at low volumes but at high volumes the protection circuit will turn off the device.

You might have your speakers shorted. Check the wiring at the amp and speaker terminals

The proper way to do this would be to use the audio output from the TV, either analogue left and right or the optical port, and send it into an dedicated amplifier or AV receiver. You can then use the amplifier or receiver to power the external speakers. If you are using a dedicated amplifier with no volume control you will want to change the audio output setting on the TV to "variable out" as oppose to its current "fixed out"settings. You can find this in the TV menu, usually under the audio settings. This will allow you to use the current TV remote to adjust the audio volume coming out of the external speakers.