I really recommend the thiersch blue. It has everything the original m7 has plus a tiny bit more sparkle.
Cool... This has the Red installed I will see how it handles my regulars.
I've not had a mic with a Red, but the red is supposedly made the same as the M9 capsule (mylar plastic instead of PVC in the M7) and I have some Gefell mics with M9 capsules but they're not tube mics. They're a bit brighter than the M7 capsules and a little cleaner although as far as I know the backplates are the same so it's probably all down to the fact that mylar is a little less "stretchy" than PVC and modern mylar is far more consistently flat than PVC sheet.
What I don't hear with the mics that have the M9's is the midrange sheen that the M7/U47 has. Not sure how much of that is the capsule though.
So... Unfortunately the mic was not as perfect as I hoped. Apparently the seller botched the built and had Chris over at Barbaric repair and test it. The builder made a critical error and did not protect the capsule while soldering, so the Thiersch Red line has 4 flux blobs on it. Trying to work it out... Seller has been good, but not too forthcoming with all the info behind the build.
Note to self... Get pictures of the capsule on diy builds!
Insanity Music Technology, owner
Delaware Film Company, engineer