Indeed, that series of Zee-nuts certainly DO have a magnificent sound, mainly attributable to that healthy sizing
of its main speaker . . . .no puny little 4-5 incher being used there !

Seems like I remember the mechanical details of the electrostatic in question, having its main half “clamshell” housing
being molded from fiberglass, with extended side flanges molded on for mount screws . . .but most got mini-stapled on,
if used upon a wood mount.

That resin mix was containing either a pale green or off white pigmenting agent. The use of small rivets, appropriate
washers front and back, and a terminal, all then being compressed in the mix to afford interfacing with the units two
terminal wires. Their drive, is being coupled in from the AF output tubes plate thru a DC isolation / coupling capacitor.



The worst enemy I have seen through the years is the presence of heavy smoke from a “smoker” such that with time,
particulate matter will be attracted to the charged elements and stick, line up, and then daisy chain into mono tubes to finally make an inter-elemental shorting action.

Probably, and hopefully yours has not been beset with this condition. All-in-all have found these units to be quite well
built and reliable.

NOW what I really, really think is that you just possibly might be over expectant in the actual treble output that is
actually produced by one of those Zenith units.

Its actually only going to produce the highs of the sssssss’s in the word lisssp, or the brushes in the drum section, or
the crinkling noise of cellophane being folded. A hard cone tweeter…. it is NOT… in its treble output level.

An ear placed right up to it would be sometimes questionable in a evaluating of its effect with the main speaker
operating.


What I would suggest is the unplugging of one of the clip connectors going to the main speaker and subbing in of a ~5
watt load resistor of 5-10 ohms in place of the speaker as a load. . . .don’ wanna mess up the output transformer !


Then, you activate the radio, preferably on a good FM station with a good full range music source, listen to that
electrostatic tweeter an it should be producing what I typically would describe as the sound of a High Voltage corona
arc, being modulated with the very highest frequencies, that being created by electrostatic flexure of that center mylar
diaphragm and with that sound escaping forwards, thru the frontal micro MULTI perforated grille work.