I have a Neumann 582 valve mic system with an M58 omni head which all works fine. I've been trying to use an M71 large diaphragm capsule (also Gefell standard screw fit) on the 582 body and my question is there a modification needed to the mic electronics to make it properly compatible? I'm getting a signal but the output is low really and noisy. The M71 head is in fine condition as it works perfectly on my Gefell M691 P48 body.
I noticed on the electrical mic list that you have a bunch of 582's with fixed M71 heads, and other 582's which a fully modular, can anyone shed any light on this? Thanks!

Is the m-71 capsule a multi-pattern (or same as the M-70)?

Hey:

The M71 is the multi-pattern head, and cannot be made to work on the 582. It requires two polarizing voltages for the two membranes, or a biased back-plate (I don't remember which) and the 582 does not hae this facility. There is a second contact (the ring) on the M71 head, which protrudes from the base and makes mounting impossible. If you do make a connection with a partially-attached capsule, the third contact will be floating, and I don't know what that will do, but obviously it doesn't make for a working microphone.

If you want to use a large diaphragm head on the 582, it must be the M70.

edited

The 582 indeed cannot make a M71 (cardiod only) or UM70 (multipattern) work. However, there was a generation of 582 mics from Gefell called the 582h which can use the M71 capsule. a 582h CANNOT use the small diaphram caps without destroying them. You can also have the mic modified from a 582 to a 582h. Bill Bradley (themicshop.com) sells these mics, c-tech in canada (the northamerican gefell repair shop) can also mod the mics for a reasonable amount of money.

In my opinion, it is very worth it. Most of the M71 capsules are an original pvc M7. Putting this on a tube body (assuming it is in good shape- a lot of 582 mics need to be really rebuilt as they got a lot of really crappy parts behind the iron cutrain) is a really wonderful mic. The original m7 is a pretty magical diaphram.

Is that too much information for you?

Frost
Owner, Narnia Productions
Chicago IL

Thanks Frost- Do you have the specific modification info, is it just for a higher polarizing voltage? Conversely, does that mean it's not a good idea to use my M582 designated cap (an M58 omni) on the M691 P48 body (which was supplied with the M71)?

Steve, my M71 is definitely Cardioid only, with two contacts. It does have a dual sided M7 type cap but only one side is connected. I thought the M70 was the end-fire KM84 inspired capsule?