We have just acquired a classic ribbon microphone in the form of the Beyrdynamic M260 N circa 1965. The seller said it was rattling and might not work so, personally, I wasn’t holding out much hope. This is an interesting microphone in that it’s polar pick-up pattern is hypercardioid as opposed to the usual figure-8 associated with most ribbons, this is to do with the way the ribbon is mounted in the microphone. It’d great on guitar cabs, hi-hats and sounds of a similar nature and boasts a flat frequency response from 40hz to 18khz.
After bit of research I discovered that the windscreen comes apart in the centre, revealing the ribbon capsule. Upon opening it was fairly obvious what was causing the rattling sound, the plastic peice which protects the ribbon had come loose. I managed to carefully unpick the entire piece to reveal the ribbon sat in the centre of the magnet. The ribbon looked in very good condition, no marks, dents or anything.
Next I very carefully cleaned the magnet each side of the ribbon to remove some of the rust. I use isopropyl alcohol and a swab, being very careful not to get any particles on the ribbon.
Next some superglue was supplied to the outside of the magnet, again being careful to get it nowhere near the ribbon. Only using the minimal amount. The plastic cover was then re-fitted and the small pieces of tape re-attached.
The repaired microphone was then tested. The microphone does not have the standard XLR fitting of a modern microphone instead having a Klein Tuchel type connector, fortunately I already have and old AKG which used the same connector so was able to borrow the lead for testing the microphone.
More information on this microphone model can be found here, at the excellent Martin Mitchell’s Microphones.