[DavGoodlin]

Hi All,
The speaker has not taken the repair (patching-cement) too well, and is coming apart due to paper cone being too brittle.
I should get it re-coned but cannot justify the $$$ since I have a Zenith Speaker (P/N 49H416) from an unknown late-30s model i picked up a while back.

The Zenith's field coil measures 580 ohms compared with the 1100 ohms of the original Philco 36-1523.
While it sounds just as good, the power supply voltage to the audio output transformer that was close to the Riders schematic value of 190v with the 1100 field is now 245 volts with the 580 ohm field. This increases the plate voltages to the AF amp and IF stages as well.

I was considering adding a series resistor to make up for the reduced field resistance.
It appears from Zenith's schematics that the Zenith speaker was intended for 6V6 outputs.
This radio has lower power PP #41 outputs, with ratings similar to a 6K6 per the RCA tube manual.

My question is: Does the lower field resistance correspond to the apparent higher power rating of the speaker? If so, would a dropping resistor be a good idea to bring the B+ voltage down to the specified 180 volts? I had also replaced the 6X5 with 1N4005 rectifiers, so that's also a factor.

Regards, Dave G

BTW - The p-p output transformer mounted on the Zenith speaker works as good as the replacement I used, noted above in post #4. I plan to remove the one under the chassis.