Hmmm... I wonder about mixing 414's with 614's in case a few blow and the rest are good. Probably a reason to stock up on 414's if using them now.
Reminds me of when they came out wid the 6146B...
There's an ex-league man who once told me this story... He was a roving salesman at GE and saw a diagram for the new 6146A on a chalkboard at RCA. He immediately told his GE design crew and they came out with the 6146B soon afterwards, trumping the 'A.' I don't know how true the story is but that's what I was told.
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