Reverb Tank - Accutronics, 4AB3C1B, Long Decay, 2-Spring

The industry standard for years, the Type 4 is still manufactured today using Hammond’s original design. Counter wound and coupled springs deliver superior mechanical performance and the classic sound that helped make the Fender Twin Reverb Amps famous.

• Replaces: 4AB3C1B
• Solid, sturdy construction
• Type: Long (2 Spring) tank
• Decay: long decay
• Input: 8 Ω
• Output: 2,250 Ω
• Connectors: Input insulated/output grounded
• Locking: No lock
• Mounting: Horizontal/open side down

Compatible amps include tube reverbs from 1963-1990 such as the Princeton Reverb, Vibrolux Reverb, Deluxe Reverb, Super Reverb, Pro Reverb, Twin Reverb, Quad Reverb, Super Six Reverb, Vibrosonic Reverb. This also includes all reissue equivalents. Also includes Fender® ’63 Reissue Reverb Unit, Fender® Concert II, Mesa Boogie® MK2C plus other models, LAB® Series L5, L7, L9, Koch® Powertone I, B-52® AT-100. Also compatible with some speaker-driven, type F, vintage Ampeg® amps such as B12X, B12XY, Echo Jet, Echo Twin.

New production Accutronics tank.

Questions about reverb tanks? See our tech articles for more information.

Product Measurements

Springs: 2
Input Impedance: 8 Ω
Output Impedance (Zout): 2.25 kΩ
Decay Time: long (2.75 to 4.0 s)
Connectors: input insulated, output grounded
Mounting Plane: horizontal, open side down