Dollysowner. you are right on point, these are London recordings, black tape, Dolby encoded, NO SSS! they leave nothing on any rollers, guides or heads, and in both instances, the screaming started on side 2, after which I cleaned the tape path, within minutes the squealing started up again no matter which of my 3 machines I used, too bad as both were very good sounding recordings, and I don't think that these particular recordings are or were available in any other tape format, although I hope I am wrong. Also, I have other Londons with similar provenance (dolby, black tape) that have not shown any signs of squealing, so I am not sure what is going on hear (hehe). Of course, these other Londons may develop the same problem, I'll just have to see...
Steve, no, I was not the original owner of the LS tapes, these were bought mostly en mass at a second-hand record store in Balt. I would say about 40% had the dreaded squeal, they were my first introduction to tape squeal. Too bad, I have found that many of the LS recordings are really good, just got a killer today, Also Sprach Reiner/CSO 1962 version. I have found that the LS tapes are prone to edge ripple and just plain bad sound on occasion, I don't buy any tapes I can't return because of this, I find about 25% of tapes are bad with various ailments, even BC's. Some sellers on ebay are good about returns, some others, well, not sure but ddtsomething something on ebay only sells bad tapes with no returns...