Spectrograms of high-frequency Pn,Sn phases recorded on ocean bottom seismographs contain frequencies in Pn and Sn wavetrains as high as 10 Hz and 7 Hz, respectively, at distances in excess of 3700 km. These and other observations confirm earlier evidence for remarkable efficiencies of Pn and Sn propagation, with Sn often more efficient (higher apparent Q) than Pn.