Fender Reverb Unit 4 Spring 4AB3C1B

Long-Decay Four-Spring Reverb for Compatible Fender Amplifiers

The Fender Reverb Unit 4 Spring 4AB3C1B is a direct replacement spring reverb unit for compatible Fender amplifiers. Its four-spring design provides a long decay of approximately 2.75 to 4.0 seconds, making it suitable for restoring the onboard reverb response of amps originally fitted with this specification.

The unit has an 8-ohm specification with RCA-style input and output jacks. It is designed to mount horizontally to the floor of the amplifier cabinet with the open side facing down, so matching the original mounting orientation and reverb unit type is important when confirming compatibility.

It is used across selected Fender models including Prosonic, Showman 50, ’94 Twin, Custom Vibrolux Reverb, Custom Vibrasonic, Pro Tube Series, Vibroverb, '65 Twin Reverb, '65 Deluxe Reverb, '65 Super Reverb, '65 Twin Custom, Vibro-King, Dual Professional, Super-Sonic, '64 Vibroverb, Princeton & and '65 Princeton Reverb amplifiers manufactured from 1991 onwards.

At Riffs & Licks Music, we think this spring reverb unit is a practical replacement for compatible Fender amps that require the 4AB3C1B four-spring format with long decay and RCA connections.