FRANCINSTIEN FS1 - Studio processor

The FRANCINSTIEN FS1 Studio Stereo Enhancement processor which was developed for recording studios and used on many famous records and film-scores. Indeed the FS1 is still in use in many studios even today.

The FRANCINSTIEN FS1 took another approach to solving the limitations with recorded stereophony. Instead of narrowing the high-frequency stereo image to match the narrower low-frequency image as is done in the original processor, the FS1 used circuitry to widen the bass image to match that of the treble image. This is possible to do because the ears perceive direction at LF due to the phase differences at the ears and, with suitable processing, these may be exaggerated at low-frequencies so that the low-frequency image is actually wider than the speaker base-line.

Because this is a rather dramatic version of the FRANCINSTIEN stereo correction, the FS1 was termed to offer Stereo Enhancement.

In the software emulation of the FRANCINSTIEN FS1 in the Stereo Lab, a setting is chosen which gives a moderate degree of "stereo enhancement" and is suitable for all genres of music.


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