One problem with ribbons is that the HF response could easily drop off. Placing a perforated fibre baffle on each side of the ribbon within the housing gradually lifts the HF by means of resonance.
The shorter ribbon allowed the mic to be tilted to a greater
degree than was permissible with the AXBT, which was limited to 20°.
At greater angles than this there was cancellation of the higher frequencies
due to the length of the ribbon being similar to the wavelength of the incident
sound, although in the days before EQ was available in the studios, tilting
the mic could cure a speaker of excessive sibilance. The same could not
be done with the PGS.
Why PGS? It stands for Pressure-gradient Single, the 'S' referring to the single magnet.
Why PGS? It stands for Pressure-gradient Single, the 'S' referring to the single magnet.