MXL 770 Microphone-Parts kit Mod
Replacing the capacitors that are involved in the signal path is a fairly straightforward mod. The MXL 770, like the 990, has a single circuit board - the preamp and the power supply, unlike the v67g, are on the same board. The kit from microphone-parts.com includes all of the parts you need to upgrade the signal path. It includes replacement capacitors, as well as replacements for the JFET and the two output transistors.
With this mic, it is probably easiest if you completely remove the board from the mic body, which just involves unsoldering the wires from the capsule and the XLR jack.
Below, we have removed all of the parts that will be replaced by the kit.
Here are the two circuit boards with the new parts in place (we did a pair of these, using a matched pair of RK-12 capsules).
Below we see the modded circuit board ready to be mounted back into the mic frame. Also, you can see that the RK-12 capsule is already mounted and ready to be wired to the Omni / Cardioid switch (next section).
