MXL V63m Capacitor Mods
Replacing the capacitors that are involved in the signal path is another fairly straightforward mod. Like the MXL V67g, the MXL V63m has two circuit boards - one for the preamp section, and one on the other side for the power supply. The main difference in the preamp is that the V63m is a transformerless Schoeps circuit clone, where as the V67g utilizes a transformer output. Below is a before and after picture of the preamp section. Basically, we replaced all of the capacitors on this board, as they are all involved with the signal path. There is also one capacitor on the backside of this board which is critical. It is between the capsule and the gate of the FET, and we want a high quality cap here. There are differing opinions on what to use for these, but there seems to be a general consensus that WIMA caps work well for all of the preamp caps. As you can see in the picture below, we removed the entire capsule assembly during this process. This really isn't neccessary if you leave the basket in place to protect the capsule while you are replacing the capacitors.
The capacitor on the backside of the preamp board is shown below. This may be the most critical capacitor to replace. You can easily gain access to this capacitor, as well as the solder side of the preamp board, by simply removing the power supply board.
Below is a picture of the power supply board (top). There is only one electrolytic on this board, which can be replaced with a higher quality Panasonic eletrolytic if desired. These are less critical, as they are in the power supply, but, or course, clean power is important.
We have replaced the signal path capacitors with WIMA caps of the same value. Below, we can see the red rectangular WIMA caps in place on the preamp board.
This capacitor mod, along with the headbasket mod (see next section), go a long way towards improving this mic.