Hammond BV Preamp Codes

[shelbykitcar]

So does anyone know the differences among all the different codes of preamps for the Hammond BV? I see a kit on tonewheelgeneral that upgrades the entire preamp to a code K. I know my organ has a code J, but I can't see the piece that is with the kit (looks like a adjustment of some sort). So I was curious if anyone knew the differences among them.

[torea]

So does anyone know the differences among all the different codes of preamps for the Hammond BV? I see a kit on tonewheelgeneral that upgrades the entire preamp to a code K. I know my organ has a code J, but I can't see the piece that is with the kit (looks like a adjustment of some sort). So I was curious if anyone knew the differences among them.


Hey, while doing some CV research yesterday, I found this schematic. It has code listings on it, is that what you're asking about?

[shelbykitcar]

Well, yes and no. I have the same schematic. Just not sure what I'm seeing is all. Lots of things changed over the codes, so just curious what the exact specs of a code K preamp would be.

[Guitarbro]

from a code J to code K, R8 and R9 change to 1.8 meg and R7 change to 3.3k