Hi folks,
I've enjoyed the discussion on declicking soundfiles of digitized vinyl and/or shellac. One technique I think that may have gone unmentioned is the 'Copy Other Channel' tool, available in Sound Forge. I've been pleasantly surprised at how often a loud click in one channel has an undamaged near-twin in the opposite channel. Of course this is more useful when the original was a monaural recording, but it has become one of my reasons for making stereo transfers of mono records--there's bound to be plenty of cases where I can borrow undamaged or nearly undamaged signal from the other groove wall.
Once a click has been zoomed in on and found to be a good candidate (less damaged or click-free audio in one of the two channels), one highlights the click in whichever channel it appears. Then click on the Copy Other Channel button.
The other nice option is to use the pencil tool to redraw the damaged area, using the click-free channel as a model.
Now as to reassembling broken 78s, I've used crazy glue with some success. (It's always best to use less of this glue rather than more. Less crazy glue will spare you a lot of mess, and will set much faster.) But I much prefer using 2-inch wide clear packaging tape to put broken 78s back together (long enough to capture their audio).
The basic recipe:
* arrange the pieces of the record on a very flat surface, such as a sheet of plate glass
* hold them together real snug with one hand (a helper may be useful)
* position and apply tape with the other hand, so that the break has a good area of tape all around it
* still holding the pieces tight, press the tape down completely
If the above steps have been done accurately, the opposite side of the record may now be playable. Capture it's audio a.s.a.p. If there are passages where the tonearm sticks in a groove or jumps ahead (and if you have a steady hand) you may be able to use a bird's flight feather (or something gently springy) to restrain the tonearm, or to urge it along.
Once the audio from this side has been transferred, move your patient back to the plate glass. Try taping up the side just captured _before_ removing the tape from the first procedure. On a good day, the alignment that worked well for side 1 will also be okay for side 2.
I've never had the slightest problem with stickum from the tape remaining on the surfaces of any record. I normally use Scotch 3M clear Packing Tape, but have had no problem with off-brands either. Certainly, remove all tape sooner than later, assuming the record isn't going into the trash (make back-up copies first).
Where the process can get tricky is that record pieces don't always fit back together as closely as we need them too. Keep a loupe on hand, to check whether the groove-ends are aligning properly where edges are butted together. If you can't seem to get them to align no matter how tightly you hold the pieces together, a very little bit of strategic filing of the raw edges (using an emery board or similar) can make all the difference.
I recommend this technique highly, because I've used it to digitize records that were broken in as many as five pieces.
Microgroove recordings are not entirely beyond hope. The first time I ever reassembled a broken record (temporarily, but long enough) was such a case. Crazy glue was used, rather than tape.
I put before/after sound files up on my creaky old website, way back around the turn of the century. If earthlink hasn't gotten too tired of my being slow with payments, you may be able to hear these files here:
http://rodbrown.home.mindspring.com/soundsaver.html
If the link doesn't work for any reason, interested readers are encouraged to send me a shout. I can email the files to you off-list.
I hope the above suggestions enable the salvaging of some deserving audio.
Best wishes, Rod
Rod Brown 44 Larry Lane Oakland, CA 94611
510-531-7131 rodbrown@xxxxxxxxxxxxxx