Description

MKR now offers mail-in preamp rebuild service for 2-tube preamps found in the earliest Hammond organs from the 1930s and early 1940s such as model A, BC, BA, AB, and model D. There were at least 5 different circuits of this preamp. You may decide whether to keep your preamp at its stock version, or to be rebuilt to version 1 (which is the cleanest version.) Some of these preamps may have a failed output transformer which may increase cost. Every component (resistor and capacitor) is replaced, with the exception of any oil-filled tub capacitors, as long as they test well. A fuse is added. Due to long length of resistors, mil-spec extra long lead resistors are used. Worn or noisy tubes are replaced as needed. Tube sockets are cleaned, tone control pot is cleaned. Preamp is fully tested both on bench and in an organ before sending back.

How it works:

1. MKR will ship a box to you containing a hardshell soft foam interior case with pre-cut packing foam, detailed instructions, and a prepaid return shipping label.
2. Follow the instructions to carefully uninstall and pack your preamp.
3. MKR receives preamp and performs Full Rebuild. Please allow 4 to 6 weeks for rebuild service to complete.
4. MKR ships preamp back to you. Follow instructions to carefully reinstall preamp into organ.
5. MKR requests that the box and hardshell case then be shipped back at your own expense. Once received, you will receive a $100 refund.

Free phone or email technical support is offered with all services. Due to extreme age of 2-tube preamps, no warranty is available.

Tools required:

• 60W or higher soldering iron, solder wick, and 60/40 solder
• Standard size flathead screwdriver (for mounting screws)
• Needle nose pliers (to aid removing or reinstalling preamp wires)

Skills required:

• Soldering and desoldering
• Familiarity with basic hand tools
• Caution, and detailed reading and following of instructions

⚠️If in doubt that you can perform above tasks, do not do this. Call a local tech.⚠️

📝Note: Not all issues are caused by the organ preamp. If you aren’t sure whether your problem(s) are preamp related, please contact us before purchasing this service.📝

📝Offered only in USA.📝