“A tidbit: When my dad invented the Type BK-12, it was the first-ever moving coil dynamic mic to have enough windings on the coil to allow elimination of a transformer in the mic, hence the tiny size and light weight. RCA had to buy two extremely expensive Swiss wire-pulling machines to make the ultra-fine wire required for the Type BK-12. My dad’s colleagues considered it a major achievement for him to have convinced the higher-ups at RCA to buy them. Good decision, though, since the BK-12 kept alive the mic production at RCA a good few years longer than otherwise would have been the case.”