Cram ́ er-Rao bound (CRB) has been formulated in

earlier work for linear, planar and 3-D array configurations. The

formulations developed in prior work, make use of the standard

spatial data model. In this paper, the existence of CRB for the

spherical harmonics data model is first verified. Subsequently, an

expression for stochastic CRB is derived for direction of arrival

(DOA) estimation in spherical harmonics domain. The stochastic

CRBs for azimuth and elevation are plotted at various Signal

to Noise Ratios (SNRs) and snapshots. It is noted that a lower

bound on the CRB is attained at high SNR. A similar observation

is made when larger number of snapshots are used.