Phase differences between irradiance and full-disk velocity variations are derived for l = 0, 1, and 2 modes with order ranging from 11 up to 30 (1.8-4.3 mHz). Irradiance measurements from the IPHIR instrument flown on the PHOBOS mission to Mars during the second half of 1988 and simultaneous velocity measurements obtained at Tenerife are used. The IPHIR instrument measures broad-band irradiance fluctuations and the derived phase differences are therefore typical of the deep layers of the photosphere. A smooth variation of the phase difference is found between irradiance at 500 nm (5 nm FWHM) and velocity from about 70 deg at 1.8 mHZ to 145 deg at 2.5 mHz, while it remains roughly constant at 145 deg up to at least 3.5 mHz, and possibly up to 4.3 mHz. It is shown that the phase differences between the green (500 nm) and red (865 nm) channels does not differ significantly from zero below 3 mHz, while a small difference of about 10 deg may exist at higher frequencies.