[morzh]

And, speaking of the tweeter speakers being counter-phase and the series capacitor being too low: my though of why no one noticed that initially is: the main speaker, used by Philco, is the same exact speaker that 37-116 and 38-116 use, with the exception of the field coil resistance (which in these is low, as they are used as filter, and in 38-690 is high as it is used as a load and not as a filter) - the PN for the cone and voice is the same. So, the speaker being a full midrange sufficient for producing Hi-Fi sound, the absence of the tweeters' action was well masked by the main speaker's performance.