In SEISAN the instrument response can be stored as pairs of frequency, amplitude and phase or as poles and zeros. The formats that can be used include GSE2, SEISAN, SAC and SEED. The SEISAN, SAC and GSE response formats are described in Appendix C. For a detailed description of the GSE format, the reader is referred to GSETT-3 . The program RESP creates response files in SEISAN and GSE format. SEED format response files can be extracted from a SEED volume.