[Nathan Slingerland]

They are different speakers.

All of the 16B tombstones use the H-13 speaker (the cathedral uses the smaller K-17 speaker). The consoles use the U-2 speaker. The later mounts differently and has a heavier duty field coil than the H-13. The chassis are similar but different code numbers. The tombstones would typically be code 121 (5-band) or 125 (4-band) while the console would be 122 (5-band) or 126 (4-band). The consoles use the 5Z3 rectifier while the tombstone chassis use an 80 tube.

Speaker details in Ron's speaker spreadsheet which can be downloaded here:

http://www.philcoradio.com/phorum/showth...hp?tid=215

Details on the rectifier and code number differences:

http://philcoradio.com/phorum/showthread.php?tid=15652