Have 2 B&W 703s as my main speakers, 2 B&W 705s as my surrounds, HTM7 as my center.What subw

I am looking to buy a HSU research subwoofer. I heard they got some good reviews. Can anyone recommed a specific model that would be consistent with the above system. Also what kind of amplifier system would I need? Would I need separate preamps, amps for my surrounds, main speakers and subwoofer? any suggestions?

Hi.Unless you have a very big room a subwoofer would be a waste of money.Your B&W 703 Speakers go down to 38 HZ.If you bought a sub. you probably would not hear much below 40 HZ.The idea of a sub in the first place is to hear (and feel) frequencies down to about 20 HZ. A 20 HZ note is about 56 feet long.If your room is about 28 feet long in one direction you will hear (feel) half a note. Any shorter than 28 feet wont be heard.The reason people hear the very low notes in a Cinema is because the inside of the building is usually longer than 56 feet. That's why the note is developed properly. When we try to do that at home we are up against the laws of physics and acoustics.

I am not trying to talk you out of getting one i am trying to show you all the problems associated with subs.The structure of the walls of your home cinema room will determine the behaviour of the low notes from a sub.Also ,each room has a fundamental resonance caused by the volume of air in the room at a certain frequency generated by the loudspeaker. The worst shape for a room is a cube where soundwaves reflect off parellel surfaces creating standing wave patterns which are very overpowering and boomy. The next worse shape is a square room which is nearly as bad as a cube.If the walls of your room are thick and dense ,the bass notes will not pass through and it will take too long for the reverberation to stop and interfere with the other frequencies A thiner wall will absorb some of the bass and transmit some energy through the wall creating a booming sound on the other side. If you spend the money on a better amplifier ,you will have a much cleaner bass that will still go low for you to enjoy the sound affects properly