Welcome To the Hoffman Amplifiers Forum

September 08, 2025, 09:37:10 am
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Blues Jr. Reverb Problem  (Read 2344 times)

0 Members and 1 Guest are viewing this topic.

Offline dpm309

  • Level 3
  • ***
  • Posts: 503
  • I love tube amps
    • Matthews Amps
Hoffman Amps Forum image
Blues Jr. Reverb Problem
« on: September 23, 2017, 02:28:59 pm »
Trying to get the reverb working on a Blues Jr. Measured the resistance on the input side and am getting about 700 ohms but on the output side, I am getting no continuity. Removed the tank and noticed 2 wires broke off the end of the springs on the output side. Rewired it and am still not getting any continuity. The tank is numbered 8EB2C1B. Plugged in the reverb tank from my revibe unit (9AB3C1B) and am only getting a distorted sound when I turn up the reverb control. Would this be caused by using a different reverb tank in the BJ? Or am I looking at something wrong with the reverb circuit. Checked the resistors and diode associated with the reverb circuit and can't find anything wrong. Am getting -16V on the anode side of D14. This is the Blues Jr. Rev A cream board version. I attached a copy of the schematic which is hard to read but the only copy I can find.
Any suggestions?
Thanks

Offline sluckey

  • Level 5
  • *******
  • Posts: 5075
    • Sluckey Amps
Hoffman Amps Forum image
Re: Blues Jr. Reverb Problem
« Reply #1 on: September 23, 2017, 02:37:06 pm »
Your revibe tank won't work with the BJ circuit. Get a proper replacement tank. AES has it...

     https://www.tubesandmore.com/search/node/8EB2C1B
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline dpm309

  • Level 3
  • ***
  • Posts: 503
  • I love tube amps
    • Matthews Amps
Hoffman Amps Forum image
Re: Blues Jr. Reverb Problem
« Reply #2 on: September 23, 2017, 02:56:22 pm »
That is what I suspected. Will go ahead order one.
Thanks

Offline dpm309

  • Level 3
  • ***
  • Posts: 503
  • I love tube amps
    • Matthews Amps
Hoffman Amps Forum image
Re: Blues Jr. Reverb Problem
« Reply #3 on: September 24, 2017, 10:25:27 am »
Are there any major differences between the 3 8EB2C1B reverb tanks from AES? The Belton and Fender MOD tanks are a few dollars less. I read on Bill M's website that the wires in Acutronic tanks are prone to breaking off. and causing other problems.

Offline sluckey

  • Level 5
  • *******
  • Posts: 5075
    • Sluckey Amps
Hoffman Amps Forum image
Re: Blues Jr. Reverb Problem
« Reply #4 on: September 24, 2017, 10:42:54 am »
Probably not much if any differences. The Accutronics unit does not include rubber grommets.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline dpm309

  • Level 3
  • ***
  • Posts: 503
  • I love tube amps
    • Matthews Amps
Hoffman Amps Forum image
Re: Blues Jr. Reverb Problem
« Reply #5 on: September 24, 2017, 01:31:00 pm »
Thanks Sluckey. I will go with the Belton unit. From the reviews I read, the MOD tank sounds different than the typical Fender reverb, more of a Marshall type sound.

 


Choose a link from the
Hoffman Amplifiers parts catalog
Mobile Device
Catalog Link
Yard Sale
Discontinued
Misc. Hardware
What's New Board Building
 Parts
Amp trim
Handles
Lamps
Diodes
Hoffman Turret
 Boards
Channel
Switching
Resistors Fender Eyelet
 Boards
Screws/Nuts
Washers
Jacks/Plugs
Connectors
Misc Eyelet
Boards
Tools
Capacitors Custom Boards
Tubes
Valves
Pots
Knobs
Fuses/Cords Chassis
Tube
Sockets
Switches Wire
Cable


Handy Links
Tube Amp Library
Tube Amp
Schematics library
Design a custom Eyelet or
Turret Board
DIY Layout Creator
File analyzer program
DIY Layout Creator
File library
Transformer Wiring
Diagrams
Hoffmanamps
Facebook page
Hoffman Amplifiers
Discount Program