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.
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.