In order to reproduce audio over headphones as in- tended, it is essential to have well-defined and con- sistent references of how headphones should sound. With the aim of stereo reproduction in mind, the field has established a de-facto reference target curve called the Harman Target Curve to which headphone transfer functions are commonly compared. This contribution questions if the same target curve is suitable when used for the reproduction of spatial audio. First, the ori- gins the Harman Curve are revisited; it is motivated by the frequency response of loudspeaker playback in a specific listening room. The necessary measurement procedures are described in detail. Then, the paper discusses the applicability of existing targets to spa- tial audio. Therein, it is possible to embed convincing spatial room information directly into the production, thereby calling into question the motivation for incor- porating a listening room in the headphone target. The paper concludes with a listening experiment that com- pares the preference of different target curves for both spatial audio and stereo
