Modern Hebrew spirantization is an allophonic distribution where the stops [p], [b], and [k] regularly alternate with [f], [v], and [x], respectively, with the fricatives surfacing post-vocalically. There are exceptions to spirantization, with stops occurring post-vocalically and fricatives surfacing elsewhere. Additionally, variation has been attested in the regularly alternating pairs. Seventy-four native Hebrew speakers rated the acceptability of variation in regularly alternating pairs and exceptional segments. Results showed that, as hypothesized, variation was less natural than the expected form of a given word. Furthermore, variation in exceptional segments was rated less natural than variation in regularly alternating segments.