SURVEY: how high can your subwoofer go?

[paulspencer]

How high can your subwoofer go?

Not so long ago I had my subs crossed at 80 Hz with a 4LR and the bass was disapointing. Although calibrated flat (both sub and mains), bass was lacking accuracy, especially acoustic double bass. I now have subs crossed much lower, more like 40 Hz, and it is noticeably more articulate. Even better is no subs at all with my mains calibrated flat to the same response as that which I get with the subs.

My subs are AE speakers AV12 in a 70L sealed box - dual mono.

I've heard similar comments from Rob Wells on this forum about his tempests.

I'd like to hear from others on their experiences with subs vs subwoofers on the accuracy of their subs in the 40 - 120 Hz range.

Linkwitz uses the XLS up to 120 Hz in his dipoles and I've also heard the XLS used up to 80 Hz in a very high end commercial speaker, so I'd say the XLS must perform better on the top end.

I wonder how some of the better subs perform in this area - subs like TC2+, some of the new Dayton subs with shorting rings, Rythmik audio servo sub, and new offerings from Adire and Avalance.

What are your experiences?