its got two power transformers and HV supplies, one for the audio amp, one for the reciever. Those are the ones with the rectifier plugged into the top. The audio output does appear to be bi-amped. The schematic shows a 6F6 driver with an odd interstage transformer coupling it to the p-p 6L6G output stage. The reason I say its odd is because it looks like it has two secondaries, one is the grid drive for the 6L6 tubes, the other looks for all the world to be output to two speakers wired in series.
http://www.nostalgiaair.org/PagesByModel/255/M0013255.pdf
print isn't very clear but the audio amp section is down in the lower right hand corner. As you can see, this is quite a complex set. The tube count is kind of padded though. If you look at it, its got one tube for an oscillator and one for a mixer. Most things combine this into one tube. It also has a seperate AVC and detector tube, where a lot of things combine this function. One thing of interest is the "magnetic tuning", which is actually AFC. That was quite uncommon for AM sets, and particularly for this time period. This thing also has variable IF bandwidth via some sort of mechanical adjustment of the IF transformers.
