Accutronics Reverb Tanks

Almost all the reverb tanks that one sees for sale are the Accutronics brand. They are made by:

Sound Enhancements, Inc.
185 Detroit St.
Cary, IL 60013

Although they make many models, the three types that are readily available are a limited number of their types 4, 8, and 9. The type 4 is 17" long and uses 2 long springs, each of which consists of two springs joined in the middle. Thus, Accutronics considers this model a 4-spring unit. This type was the original style selected by Leo Fender. The type 8 is 9" long and uses 3 springs. This type is most famous for its use by Marshall. The type 9 is 17" long and uses 3 long springs, each of which consists of two springs joined in the middle. Analogously, Accutronics considers this unit a 6-spring device. All Accutronics' part numbers consist of 7 characters as described below.

1st character: type 4, 8, or 9

2nd character: Input impedance @ 1kHz
Type A B C D E F
4 8 ohms 150 ohms 200 ohms 250 ohms 600 ohms 1475 ohms
8 and 9 10 ohms 190 ohms 240 ohms 310 ohms 800 ohms 1925 ohms

3rd character: Output impedance @ 1 kHz
Type A B C
4 500 ohms 2250 ohms 10000 ohms
8 and 9 600 ohms 2575 ohms 12000 ohms

4th character: Decay time
1 = short (1.2 to 2 sec)
2 = medium (1.75 to 3.0 sec)
3 = long (2.75 to 4 sec)

5th character: Connector arrangement
A = input grounded, output grounded
B = input grounded, output insulated
C = input insulated, output grounded
D = input insulated, output insulated

6th character: Locking device 1 = no lock

7th character: Mounting plane
A = horizontal,open side up
B = horizontal, open side down
C = vertical wall,long axis horizontal, connectors up
D = vertical wall, long axis horizontal, connectors down
E = vertical wall, long axis vertical, input up
F = vertical wall, long axis vertical, output up

The following table summarizes the above data for the most commonly available units:

PART NUMBER PRIMARY USER LENGTH NUMBER OF SPRINGS INPUT IMPEDANCE@ 1KhZ/DC

OUTPUT IMPEDANCE @ 1KhZ/dc

4AB3C1B Fender 17" 4 8ohms/.81ohms 2,250ohms/200ohms
4BB2C1B Acoustic/SLM/Ampeg 17" 4 150ohms/26ohms 2,250ohms/200ohms
4EB2C1B Peavey 17" 4 600ohms/58ohms 2,250ohms/200ohms
4FB3D1B Music Man General 17" 4 1475ohms/200ohms 2,250ohms/200ohms
9AB2C1B Fender/ Boogie 17" 6 10ohms/.81ohms 2575ohms/200ohms
9EB2C1B Peavey/General 17" 6 800/58ohms 2575ohms/200ohms
9FB2A1C General 17" 6 1,925/200ohms 2575ohms/200ohms
8AB2A1B Boogie 9" 3 10ohms/.81ohms 2575ohms/200ohms
8BB2A1B SLM 9" 3 190ohms/26ohms 2575ohms/200ohms
8DB2C1B Marshall 9" 3 310ohms/36ohms 2575ohms/200ohms
8EB2C1B Fender 9" 3 800ohms/58ohms 2575ohms/200ohms