The Prism FET Amplifier is a highly sought-after pedal conversion of the BOSS FA-1 FET Amplifier, which was originally manufactured from 1980 to 1984. The original FA-1 was an always-on effect that clipped to your belt and ran on a 9-volt battery. Despite its solid and versatile circuit, the non-standard implementation limited its popularity, until it was famously used by The Edge of U2, causing vintage prices to skyrocket.

The Prism FET Amplifier retains the same circuit as the original FA-1 but converts it into a standard pedal format. It features a footswitch, LED indicator, and a 9V adapter jack. The original FA-1 used the now-obsolete HA1457W chip, which is a single version of the LM1458. Extensive A/B testing was conducted to ensure that the LM1458 performs identically to two HA1457Ws, making it sonically indistinguishable.

As a result, the updated version of the Prism only supports dual op-amps and eliminates the option to use the HA1457W. However, the previous version of the Prism, which supports the HA1457W, is still available for those who prefer it.

Summary created by AI from the original source.