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RE: OK now I am totally confused...

Posted by Ralph on June 5, 2012 at 08:56:55:
The reason you can reduce the capacitor value is that the resistor and cap set the crossover frequency, without the resistor the impedance of the circuit at the crossover frequency is considerably higher. In fact so much higher that I suspect that 10-15uf is closer to the mark.

The transformer can be saturated by low frequencies but saturation is very different from actual damage. I think you will find it pretty hard to damage the transformer! Saturation, OTHO will manifest as temporary distortion on transients. If you were able to keep the transformer in saturation, eventually you could overheat it but it would sound bad and most reasonable audiophiles would turn the volume down at that point so there would be no time from the transformer to heat up enough for actual damage. Just my opinion mind you, but damaging the transformer seems remote, and if you have the cap (above) installed its just not going to happen.

This will result in a bumpy impedance curve. In stock form the speaker has a fairly flat curve through the midrange, caused by that resistor, and that curve is hard to drive because the resistor is where most of the power is going- that is why its rated with such a large wattage. However it appears that even transistor amps benefit from getting rid of the resistor, despite the resulting impedance curve! That is because the energy made by the amp is radiated into the room rather than being converted to heat.