wulf

I have a 2 channel NAD 355BEE with B&W CDM1NT speakers. They are a little bright as people say. I have another set of speakers hooked up also but nothing impressive even though I like them. Am I able to hook up a subwoofer or do I need to sell the speakers and get towers?

You could run the speaker cables to a sub that has speaker-level input/output and then from the sub to the speakers. Or you could run the PRE OUT 1 outputs from the NAD to a sub. You could also just run it off the 2nd pair of speaker outputs, but I suspect you wouldn't want to do that.

If the sub has speaker level inputs you can just run a second pair of speaker cables from the same speaker output on your amp (parallel wiring).

Yes you are able to hook up a subwoofer in the ways explained above the only thing I would be worried about is that hooking up a Sub will help fill out your bottom end but it will not help with the brightness you are hearing. The sound character of a certain speaker on certain certain electronics is what it is and adding a subwoofer will not fix this you will only be using a fuller and louder bottom end to try to compensate which in most cases will cause you to boost the bass to unnatural levels. Usually when people talk about their speakers being bright I start with the brand and model of speaker being used and see if it might be your electronics or cables or if other people have experienced the same brightness with said speaker. B&W speakers have been known to be bright by nature so the only way you might tame this is by going to very warm sounding electronics but if you like the electronics you have then the only thing I can say is instead of buying a subwoofer to try to compensate for brightness I would go out and listen to some of the better speakers out there and see what you can find that isn't bright. My opinion is that trying to find speakers with soft dome tweeters of good quality will be more listenable for longer periods of time and not kill your ears with brightness.

Turn your treble down.
Also "soften" the room a bit with wall panels, drapes, etc.:1: