G'day, welcome to B&O and a super forum to chat about it! Nice choice there, beautiful design. This topic is a popular one, i would say a big yes to adding a subwoofer to the 6000's. The question is, which one.
Ask your dealer for a home demo of the BL2 and see what you think of the sound. The BL2 really is good in this situation, because it filters the un-needed bass out of the 6000's which leaves them able to send you a more detailed sound, the 6000's are great, but on their lonesome, i doubt them as main speakers.
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