How to control long decay of B&W woofers ?

I agree with Newbee. It's gotta be the recordings. The fact that some recordings sound very controlled and tight means that it's not the speaker because it's proved that it's capable of stopping when "told" to.

Remember: When the B&W Matrixes came out, they immediately became the monitors of choice at Abbey Road Studios and also at Telarc; no doubt they found their way into several other studios as well. The thing is, the B&W Matrix was immediately received as a new standard in playback accuracy.

So I'd say if you're getting excessive bass overhang on some recordings and not on others ... it's the recording.

yeah...if the woofer is still moving,it's on the recording.

My set up is the same as yours, I think. I do use the Krell KBX that was set up by Krell especially for the 800's and includes the bass alignment filter. Unfortunately, they no longer make the unit and I don't think they will make the board (but you can ask them, if you find a used unit).

I have had no such problem.

Fell free to contact me directly if you have any further questions.

Richard
[email protected]

2nd thought:

Did you change the polarity of the woofers when you removed the low pass filters? You should have.

Richard

Hi Richard,
Yes, I have changed the polarity when removing the passive crossover network of the woofers. I was looking for KRELL KBX crossovers but those are no more made or available as you have mentioned already. But the crossover is not the problem here.
I have tried with good analog crossovers. I have experimented with different crossover frequencies, crossover slope, volume levels, even adding a subsonic filters as the KRELL KBX crossover provides. Still I hear the continuous background sound from woofers after the drum beat was hit on some CDs. It is definitely not the room reverberration. The woofers are really vibrating for extended period (though at a lower intensity than the sound of first drum hit) after the drum beat.
I don't know if this is acceptable to many audiophiles, but it is not acceptable to my ears. I feel very annoyed if woofers continue to make sound and do not exactly follow the drum beats. The most surprising thing is that with some CDs the heavy and deep drum beats are extactly reproduced with clean, heavy and deep bass. I have observed that about 95% (or more) of the CDs make the abnormal continuous sound from the woofers and only 5% (or less) do not. Moreover, in a particular CD some tracks do make that bad sound and some other tracks do not. By the way, I listen to pop, rock, jazz, metal, classical, and anything except rap. I am extremely puzzled that if something is wrong with the system setup, or the woofers, or the crossover setting, or associated electronics or the room, then why some tracks on some CDs can make very clean deep and heavy bass sound ?
Is it possible that 95% of CD makers did not record the bass correctly ? That is very hard to believe.
Thanks for your help
-Sunny