Johnson Millennium Info & Repairs

Info. Videos

Common Johnson Millennium Repairs

Common, Simple Repairs

A discussion of some common symptoms, likely causes, and repairs for the JM-150 & JM-250
Disassembling the Johnson Millennium

Disassembling

How to properly disassemble your amplifier for cleaning, and general maintenance, or repairs.
Updating the Johnson Millennium Operating System

OS Updates

How to update your operating system using an amplifier to amplifier transfer.
Johnson Millennium J-12

J-12 Alternatives

A discussion of alternatives to the J-12 foot controller and advanced J-3 as well as MIDI setup and functions.
Johnson Millennium J-12 damage

J-12 Controller Hazards

An in-depth circuit analysis providing information on the danger associated with using the J-12 or Digitech Control One footcontrollers.
Johnson Millennium 12AX7 Tube Changes

Changing Tubes

A rundown of changing the 12AX7 preamp tubes in the JM-150 and JM-250 amplifiers.
Johnson Millennium Computer Patch Storage

Computer Storage of Patches

How to use the Johnson Updater Software to store and receive bulk dumps and patches in the amplifier.

Requests for Repair

Using the disassembling video, it's possible for a long distance repair to be executed without sending an entire amp. One of the special services I can offer is an upgrade of JM-150s to a 250 watt power amplifier section. If you're looking for parts, I have a stock of EEPROMs and DRAMs available, and for general information you can contact me.

Background

The Johnson Millennium was a tube integrated, modeling guitar amplifier introduced in the mid-1990's. I purchased my first JM-150 in 1998 and became very comfortable with the unique features the amp had to offer. For years, there was no tool that was as advanced, flexible, or sounded as good in one package, and especially in the price range.

Professionally, it became my swiss-army knife, and even 15 years later, there are only a few products that I think have made the Johnson obsolete, like Fractal Audio's Axe-FX. I've solved many problems including replacement of EEPROMs, DRAMs, Master Volume pots, power supplies and amplifiers, etc... I have offered support for a number of people via email, and have had people drive their amps to me in order to look at them. If you have a question pertaining to the JM-150 or 250, please feel free to contact me.