This is the T18 with 100 watts in. Xmax isn't exceeded above 25 Hz, and for that matter not below it either, as the power requirements of home theatre program material are not linear, but fall rapidly below 30 Hz, while those of music program drop like a stone below 50 Hz. Not that I'd recommend anyone actually put 100 watts into a T18. With 90dB sensitivity at 30Hz corner loaded, and better than 100dB sensitivity at 50Hz, you just don't need to. But you can.