Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring
- 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.
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 insulated, output grounded | ||
Decay Time | long (2.75 to 4.0 s) | ||
Grommet Hole Diameter | 0.2 in. | ||
Input Impedance | 8 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 down | ||
Output Impedance (Zout) | 2.25 kΩ | ||
Springs | 2 | ||
Thickness | 0.04 in. |
Packaging Dimensions | 17 in. × 5 in. × 3 in. | ||
Weight (Packaging) | 1.2963 lbs. |
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Product Reviews
Great reverb tank! I had to replace the tank in a Carr Mercury V after some rough shipping popped one of the springs. This is the tank that Carr uses/recommends in the Merc V. As it was an identical replacement, it took all of 35 seconds to install it. Sounds great!
Works great. Revived the old Vibrolux just fine. As always, T&M gives great service.
Used this tank to replace the original (which had failed) in a 1968 Princeton Reverb.It fit perfectly and is more reverb than I'll ever need, the long decay time takes some getting used to, but overall I think it sounds great.
The MOD rverb tank was easy to install and sounds great. This is the brand used by Carr Guitar amplifiers.They recommended this MOD reverb tank over other more well known brands and after hearing it I understand why.
I have a 1968 SUNN Solarus amp head that I'm restoring. Someone removed the reverb tank and cut down the box approximatley 3 inches. I made a new box with the proper dimensions (24"x10"x10") installed new MOD reverb tank and new RCA cables and she's back to her glory. Thanks
I installed this tank in a silverface Princeton Reverb. The original Accutronics tank had dropped a spring when a transducer broke, and sounded terrible as a result. This tank has a longer decay than I think is typical of vintage Fenders, but otherwise sounds great! Full-on surf sounds are there if you want them, as well as more moderate settings. Installation is easy! I'm glad I did this.
I installed this tank in a silverface Princeton Reverb. The original Accutronics tank had dropped a spring when a transducer broke, and sounded terrible as a result. This tank has a longer decay than I think is typical of vintage Fenders, but otherwise sounds great! Full-on surf sounds are there if you want them, as well as more moderate settings. Installation is easy! I'm glad I did this.
Great tank!!!! I would highly recommend these and would purchase them again for sure!!!!
worked out better than stock.
Mine was loosely shipped in a bigger box with my other items. It failed after about 3 hours use. AES had me ship the defective one back which cost me more than buying one...
Now I have a two week or so wait for another tank to arrive and a customer without reverb in his amp. The tank did sound pretty good while it lasted. I could have bought one locally and will probably have to for this customer.