Ground-state lines of NH₃ 572 GHz and H₂O 557 GHz observed at the same time in the different sidebands of HIFI. Both lines show profiles characteristic of infall, but the NH₃ line lacks the high-velocity wings seen in water due to the VLA 1623 outflow. The middle figure shows the High Resolution Spectrometer (HRS) ammonia data, revealing the depth of the central absorption, and the other two the corresponding Wide Band Spectrometer (WBS) spectra at lower resolution.