Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring

Mod Electronics
Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring image 1
Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring image 2
Customer image:<br/>"Fender Princeton Amp 64 Front View"
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Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring image 1Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring image 2
Customer Images:
Customer image: "Fender Princeton Amp 64 Front View"

Reverb Tank - Mod® 4AB3C1B, Long Decay, 2-Spring

In Stock
  • 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.

Item ID:
Input Impedance:
Number Of Springs:
Output Impedance:
Tank Length:
RoHS Compliant
Connectorsinput insulated, output grounded
Decay Timelong (2.75 to 4.0 s)
Grommet Hole Diameter0.2 in.
Input Impedance8 Ω
Item Height1.5 in.
Item Length16.75 in.
Item Width4.25 in.
Mounting Hole Center to Center A8.75 in.
Mounting Hole Center to Center B3.75 in.
Mounting Planehorizontal, open side down
Output Impedance (Zout)2.25 kΩ
Thickness0.04 in.
Packaging Information
Packaging Dimensions17 in. × 5 in. × 2.5 in.
Weight (Packaging)1.2963 lbs.

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Questions? Contact us at [email protected], or give us a call at 480-296-0890

Product Reviews

5.00 out of 5 based on 28 reviews
R.Limeres - February 18th, 2024
5 out of 5

the difference is night and day from the original stock reverb that comes with the Deluxe Reverb reissue, couldn't be happier, recomended for anyone who wants to improve the sound and depth

ALAIN LAPOINTE - September 8th, 2023
5 out of 5

I've been very lucky to find two Labseries L5 guitar amps in original and mint condition in my area. The first one I got had a small (about 7 or 8 in long) two spring Milton C.0. tank in it. So when I got the second one it had a Accutronics 4AB3C1 in it. When I AB'd both amps together, I noticed right away that the first one with the small tank had weak reverb compared to the other one. After researching the web it was obvious that the "MOD" tanks had great reviews. So I ordered the 4AB3C1B from "Amplified Parts". As soon as it arrived, I replaced the short tank with the MOD and proceeded to AB Both amps. I was just floored by the absolute lush reverb coming out of the amp with the MOD reverb tank. I know it's a question of personal preference when it comes to sound, but for me, the MOD has clearly much better reverb than the Accutronics. Again, personal preference... So I ordered the very same tank to replace the Accutronics and can't wait to receive it and play my amps in stereo.... Thanks to the folks at Amplified Parts!!!!!! Very happy customer here!

Jeff Zirkle - August 31st, 2021
5 out of 5

Very good Reverb Tank at a good price point

brebar - June 29th, 2021
5 out of 5

This has got to be the the most intense reverb that I ever heard, in a good way. Much more lush than a 1960's Accutronic tank. I like it.

Dave P - April 17th, 2021
5 out of 5

The reverb tank in my 1980's Dean Markley CD60 died, and since it was an oddball tank made by OC Electronics in Wisconsin, I had no idea what to replace it with. I emailed Mod Reverb and asked for their suggestion. They suggested the 4AB3C1B. I got it and tried it out, works better than the original tank. This one has more reverb intensity to it, can do the surf verb no problem. The old one was pretty tame, even when cranked.

Robert R. - November 9th, 2020
5 out of 5

Tank works fine. Heads up, however. On my Princeton Reverb Reissue the stock tank's RCA jacks were color coded exactly reversed from the jacks on the MOD tank. After plugging red into red, white into white the reverb did not work. On closer inspection I discovered that the jacks on the stock accutronic tank were opposite from the jacks on the MOD tank. In other words, red jack on one tank was input, while red on the other tank was output. Don't know what's up with this, or who got what back-ass-wards. Fortunately "input" and "output" are imprinted on the metal housing. Take Away: go by the imprints, not just the colors.

Chris Petrich - September 19th, 2020
5 out of 5

I needed to replace the reverb tank in my Fender Princeton '65 Reverb Reissue. Very happy with the MOD tank sound. Much better then the stock tank.

Leonard L. Akins - January 8th, 2020
5 out of 5

I have completed the replacement of the reverb tanks in my fender Twin Custom 15 and fender Super Reverb this date and both sound great with my Gibson SG Standard

Leonard L. Akins - December 24th, 2019
5 out of 5

I purxhased this to repair my Fender Twin Custom 15 it now has the reverb that it once had and I am very satisfied. I now have to replace the reverb tank in my Fender Super Reverb and I have purchased the tank but have not installed it as of yet.

Chris R. - August 1st, 2018
5 out of 5

Replaced the stock reverb tank(accutronics) in my 2000 "the Twin" as I felt it sounded worn out. The Mod reverb tank sounds great & has given my amp new life.