The WA-47 full upgrade is still our #1 seller, turning this mic into a secret weapon for many top level engineers as well as many home studios. It's been a while since I listed this mod and figured that it was worth it to update folks on the evolution of this mod since it was first introduced.
I feel that this mod has finally reached a place of Zen in that it is now as thorough as I feel it can possibly get, and finally makes the mic as good as it can possibly get. I've continued to search high and low for the very best capacitors to put in this mic, ultimately settling on all Panasonic parts for the electrolytics in the PSU and mic (there are 12 of these in all), and all are of the highest temperature, lifespan, and ratings that I'm able to find. The improvement this makes is quite audible; but equally important, that the mic will last a lifetime and remain sonically consistent throughout that time.
I now do even more thorough re-building of the mic and PSU assembly. Due to the use of some fine strand wire and rather hit-or-miss crimping, I now re-terminate the ends of all grounding lugs and ground wires in the star-ground configuration (which was my idea) used in the PSU chassis. The mic body relies on a firm connection to the brass set screw in the grounding lug of the 7 pin XLR insert, which I find can be problematic sometimes... if the insert becomes lose or makes poor contact with the chassis, the chassis ground can be intermittent... and to be fair, most mics in the world do some version of this and it usually works out... I'm just nitpicky. So, I run a new chassis ground wire from the XLR ground lug of the microphone to a place on the mic's internal endoskeleton where it is mounted with a miniature ring terminal, washer, and screw. While open, the 'bottom bell' of the mic is inspected and re-worked as needed, and the bottom of the transformer PCB is trimmed and cleaned up.
I went through a lot of tubes to find the best tube for this mic. For some time, seeking just the lowest possible noise specs, I was using the TAD Highgrade 12AX7WA; but ultimately I have decided that fullness of tone matters most to me, and there are other ways to reduce noise. I tried Jan GE tubes and some other contemporary valves; but had either QC issues or supply issues with these. I finally decided to go with the JAN Sylvania 5751, which I clean and de-scale and burn in. It has a decent noise performance; but more importantly, it just has the warmth and bigness of sound that I am after. It reminds me of why I wanted the mic to have a 5751 to begin with (just a larger than life sound compared to a standard 12AX7); but does so with deeper tone and more vintage vibe. It just fills in all the cracks, sonically, for a richer, wider, deeper sound. This tube also has really good microphonic properties (pretty much none!); but I still augment that with a pair of tube damper rings.
Most of the time the capsule in these mics is fine; but sometimes, particularly on older ones, I see some issues where I feel the Mylar tension maybe is too high, it is too strident, or has some humidity behind the diaphragm, or other issues. Sometimes also the capsule saddle will be cracked and on its way to breaking due to it being a fairly rigid part, and the shipping services having their way with the packages. I now stock this particular capsule and a compatible capsule saddle. When I open the headbasket on these mics, I inspect this area (and also listen to it later, of course), and I make a judgment call on it. If I feel it needs a new capsule or a replacement capsule saddle/mount, it gets one. I do not charge for this added service.
I also now stock the very hard to find power indicator bulb, since I've had quite a number of them be out; its not uncommon for me to not only replace the bulb but to rebuild the power lamp housing as well.
I still do all of the other tweaks that I've always done to this microphone, such as dampening the polystyrene, cleaning the boards, tidying up and shortening wire lengths, spraying contacts, and what have you... but these are the new things I added. I have not raised the price of this mod even though it is now more labor-intensive than ever; so there's never been a better time to get one. See what many satisfied folks are talking about!