Reverb Tank - Mod® 4FB3A1A, Long Decay, 2-Spring
- Replaces: 4FB3A1A
- Solid, sturdy construction
- Type: Long (2 Spring) tank
- Decay: long decay
- Input: 1,475 Ω
- Output: 2,250 Ω
- Connectors: Input grounded/output grounded
- Locking: No lock
- Mounting: Horizontal/open side up
Compatible amps include most vintage Ampeg® amps with capacitance driven reverbs such as the Rocket, Reverberocket (tube-driven), Jet, Gemini, AC12, B12XT, GV15, GV22, V2, V4, VT22, VT40. Also compatible with select Kustom® amps from the 60s and 70s.
The Mod Electronics Reverb Tanks are high quality upgrade units. Some of the major differences between the Mod®s and other reverb tanks are that the Transducers are wired directly to their respective RCA jacks as opposed to current production tanks where Transducers are connected by a detachable plug to their respective RCA jacks. This makes the tanks less receptive to any outside interference. The original Hammond Accutronics tanks from the 1960s were also wired directly to their respective RCA jacks. In addition, very close attention has been paid to the spacing and size of the lamination of the Transducers resulting in a more vintage like tone.
Questions about reverb tanks? See our tech articles for more information.
| Connectors | input grounded, output grounded | ||
| Decay Time | long (2.75 to 4.0 s) | ||
| Grommet Hole Diameter | 0.2 in. | ||
| Input Impedance | 1,475 Ω | ||
| Item Height | 1.5 in. | ||
| Item Length | 16.75 in. | ||
| Item Width | 4.25 in. | ||
| Mounting Hole Center to Center A | 8.75 in. | ||
| Mounting Hole Center to Center B | 3.75 in. | ||
| Mounting Plane | horizontal, open side up | ||
| Output Impedance (Zout) | 2.25 kΩ | ||
| Springs | 2 | ||
| Thickness | 0.04 in. | ||
| Packaging Dimensions | 17 in. × 5 in. × 2.5 in. | ||
| Weight (Packaging) | 1.2963 lbs. | ||
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Product Reviews
Although I haven't installed this yet; i believe the quality of all the components are obvious. This is going into 1967 Ampeg Gemini II, that my amp tech has been ressurecting for some time. I hope it exceeds all of my expectations, and is equal to the super wet reverb that this amp was known for.
The reverb tank came in a reasonable time .
The tank works ! Sounds as it should .
Thank You
Vinny Mongeluzo
Vinny's Music Service inc.