Fender BXR300 Cutting Out

[Enzo]

I hate to strain my head too deep, but I'd say any efficiency gains will not be larger than the increased power output. As to twice, do you mean impedance?

The lowest or least load on an amp is no load at all. - no speaker. And the other extreme, say 1 ohm or even a dead short across the output would be the maximum load on the amp. The higher the impedance, the closer it is to an open circuit. the lower the impedance, the closer it is to a dead short.

[g1]

Yes, the terminology gets a bit tricky here, and we need to be specific.
Load is about current, so lower impedance is greater load. When you say 'double the specified load', I'm not sure if you mean double the load, or double the load impedance, which are opposite.
A 4 ohm load is double the load of 8 ohms. But half the load impedance.

Rated load is generally the minimum load. Adding extra parallel speakers reduces the load impedance which is a greater load on the amp. So it's not allowed, as the amp will overheat and shut-down (or burn up).

Now back to the actual amp, I had asked earlier if the internal speaker was still 8 ohm (stock), or if it had been changed to a 4 ohm. I thought you said it was 4, did I mis-read?