What makes this application a little tricky is that Bose uses low impedance speakers (0.5 ohms) on their amplifiers (located inside the enclosure of each speaker) that use relatively small amounts of power to generate decent output volume from their speakers.

Also the signal from the Bose head unit to their amplifiers is not what one would typically considered speaker level or line level. It actually falls below what is normally considered to be line level. This makes the signal a little difficult to use to drive the inputs of most amplifiers
on the market.

The output from the Bose amplifiers however, is in the 3 Volt range. That puts it at the very bottom of the Amplified Bazooka speaker level input sensitivity which if used, may not leave you with much adjustment on the LEVEL control.

To avoid this potential problem we recommend that you drive the low level inputs of the Amplified Bazooka with the high level outputs of the Bose amplifiers.

This is accomplished by cutting the RCA connectors off of the Amplified Bazooka's low level input leads, and using the Blue wires as the positive leads and the White wires as negative leads. Tie into the high level leads of one right and one left Bose speaker. These high level
leads are located inside each enclosure just behind the speaker. Make your connections to these wires and run them out of each enclosure to the Amplified Bazooka inputs.

This configuration will allow you to have much greater control over the bass level adjustment and still take full advantage of the Amplified Bazooka's balanced input circuitry.