Just going from recollection on the playing time, Eldartford. Longer may well be true, and my recollection may be for 16" 78s. The speed issue was also all over the map from 16 rpm to 90 rpm, and playback allowed for all of that variance. Interestingly to me, KAB still manufactures a "transcription" turntable that will manage those 16" discs and allow for infinitely adjustable speed control throughout this range.
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