Note from Graham 10 Oct 2005: "I bought these from eBay about 9 months ago for £103.01. I recognised them from my days at the TV Centre 1964-8 and had to have them, not knowing if they were any good. As it is they are acoustically fine if a bit battered and they are on the list for new grills and a re-spray. They were in a church hall that was being refurbed being used as PA speakers but the organist thought they might be worth something so took them back out of the skip. The organist lived about 50 yards from the Crystal Palace transmitter which was a bit ironic.They have consecutive serial numbers (about the 800 mark and will check next time I'm up the ladder) and a test label dates them as 1968.
They have the best bass of any speaker I've heard and at 18Hz will rattle the front door. The 15" Goodmans was reputed to be a guitar speaker but the low resonance one (Rf >30Hz).
I'm waiting for some good monitors (LS5/4s or 8s will do) to turn up before I work on them as I can't do without decent bass now I've discovered these!